Newer laboratory approaches for assessing visual dysfunction.

The crucial point that will be emphasized throughout this report is the potential utility of analyzing visual cortical receptive field (RF) properties of the single-cell level as a sensitive and reliable neurotoxicity screening tool. Numerous studies employing exposure of kittens to altered visual environments during the critical period have demonstrated that particular classes of RFs can be selectively affected while sparing others. There has been a rapid proliferation of new methods used to investigate such effects. An important current trend involves the development of multidisciplinary combinations of approaches. The various maneuvers reviewed here seem adaptable to studying neurotoxic insult of the sensitive properties of cortical visual neurons, particularly in the cat or monkey. Conceivably, a general disruption of cortical RF properties might be expected following toxic exposure since individual RF properties are generally not determined by completely independent mechanisms. In fact, some toxicants might produce a general degradation of RF properties akin to the electrophysiological results reported for long-term dark rearing or binocular deprivation

The study on the outsourcing of Taiwan's hospitals: a questionnaire survey research

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to assess the outsourcing situation in Taiwanese hospitals and compares the differences in hospital ownership and in accreditation levels.</p> <p>Methods</p> <p>This research combined two kinds of methods: a questionnaire survey and the in-depth interview to two CEOs of the sample hospitals. One hospital is not-for-profit, while the other is a public hospital and the research samples are from the hospital data from Taiwan's 2005 to 2007 Department of Health qualifying lists of hospital accreditation. The returned questionnaires were analyzed with STATISTICA^®7.1 version software.</p> <p>Results</p> <p>The results for non-medical items showed medical waste and common trash both have the highest rate (94.6 percent) of being outsourced. The gift store (75 percent) and linen (73 percent) follow close behind, while the lowest rate of outsourcing is in utility maintenance (13.5 percent). For medical items, the highest rate of outsourcing is in the ambulance units (51.4 percent), while the hemodialysis center follows close behind with a rate of 50 percent. For departments of nutrition, pharmacy, and nursing however, the outsourcing rate is lower than 3 percent. This shows that Taiwan's hospitals are still conservative in their willingness to outsource for medical items. The results of the satisfaction paired t-test show that the non-medical items have a higher score than the medical items. The factor analysis showed the three significant factors in of non medical items' outsourcing are "performance", "finance", and "human resource". For medical items, the two factors are "operation" and satisfaction". To further exam the factor validity and reliability of the satisfaction model, a confirmative factor analysis (CFA) was conducted using structure equation modeling (SEM) method and found the model fitting well.</p> <p>Conclusion</p> <p>Hospitals, especially for public hospitals, can get benefits from outsourcing to revive the full-time-equivalent and human resource limitation.</p

Interaction between Purkinje Cells and Inhibitory Interneurons May Create Adjustable Output Waveforms to Generate Timed Cerebellar Output

We develop a new model that explains how the cerebellum may generate the timing in classical delay eyeblink conditioning. Recent studies show that both Purkinje cells (PCs) and inhibitory interneurons (INs) have parallel signal processing streams with two time scales: an AMPA receptor-mediated fast process and a metabotropic glutamate receptor (mGluR)-mediated slow process. Moreover, one consistent finding is an increased excitability of PC dendrites (in Larsell's lobule HVI) in animals when they acquire the classical delay eyeblink conditioning naturally, in contrast to in vitro studies, where learning involves long-term depression (LTD). Our model proposes that the delayed response comes from the slow dynamics of mGluR-mediated IP3 activation, and the ensuing calcium concentration change, and not from LTP/LTD. The conditioned stimulus (tone), arriving on the parallel fibers, triggers this slow activation in INs and PC spines. These excitatory (from PC spines) and inhibitory (from INs) signals then interact at the PC dendrites to generate variable waveforms of PC activation. When the unconditioned stimulus (puff), arriving on the climbing fibers, is coupled frequently with this slow activation the waveform is amplified (due to an increased excitability) and leads to a timed pause in the PC population. The disinhibition of deep cerebellar nuclei by this timed pause causes the delayed conditioned response. This suggested PC-IN interaction emphasizes a richer role of the INs in learning and also conforms to the recent evidence that mGluR in the cerebellar cortex may participate in slow motor execution. We show that the suggested mechanism can endow the cerebellar cortex with the versatility to learn almost any temporal pattern, in addition to those that arise in classical conditioning

Generation of a Synthetic Memory Trace

We investigated the effect of activating a competing, artificially generated, neural representation on encoding of contextual fear memory. We used a cfos based transgenic approach to introduce the hM(3)D(q) DREADD receptor into neurons based on their natural activity patterns. Neural activity can then be specifically and inducibly increased in the hM(3)D(q) expressing neurons by an exogenous ligand. When an ensemble of neurons for one context (ctxA) was artificially activated during conditioning in a distinct context (ctxB), animals formed a hybrid memory representation. Reactivation of the artificially stimulated network within the conditioning context was required for retrieval of the memory. The memory was specific for the spatial pattern of neurons artificially activated during learning while similar stimulation impaired recall when not part of the initial conditioning