Unravelling strong electronic interlayer and intralayer correlations in a transition metal dichalcogenide.

Electronic correlations play important roles in driving exotic phenomena in condensed matter physics. They determine low-energy properties through high-energy bands well-beyond optics. Great effort has been made to understand low-energy excitations such as low-energy excitons in transition metal dichalcogenides (TMDCs), however their high-energy bands and interlayer correlation remain mysteries. Herewith, by measuring temperature- and polarization-dependent complex dielectric and loss functions of bulk molybdenum disulphide from near-infrared to soft X-ray, supported with theoretical calculations, we discover unconventional soft X-ray correlated-plasmons with low-loss, and electronic transitions that reduce dimensionality and increase correlations, accompanied with significantly modified low-energy excitons. At room temperature, interlayer electronic correlations, together with the intralayer correlations in the c-axis, are surprisingly strong, yielding a three-dimensional-like system. Upon cooling, wide-range spectral-weight transfer occurs across a few tens of eV and in-plane p-d hybridizations become enhanced, revealing strong Coulomb correlations and electronic anisotropy, yielding a two-dimensional-like system. Our result shows the importance of strong electronic, interlayer and intralayer correlations in determining electronic structure and opens up applications of utilizing TMDCs on plasmonic nanolithrography.

A dirhodium(II)-carbenoid route to (-)- and (+)-Geissman-Waiss lactone: synthesis of (1R,7R,8R)-(-)-turneforcidine.

(-)- and (+)-Geissman-Waiss lactone, 4b, was efficiently prepared via the intramolecular C-H insertion reaction of the chiral nonracemic diazoacetates (-)-5a and (+)-5b catalyzed by dirhodium(II) tetrakis[methyl (5R and 5S)-3-phenylpropanoyl-2-imidazolidinone-5-carboxylate]. The cyclization was found to proceed with excellent regioselectivity and cis-diastereoselectivity. The bicyclic lactone (-)-4b was successfully used in the synthesis of the necine base, (-)-turneforcidine 2.

Anodal excitation of intact peripheral nerves in humans.

The median nerves of six normal subjects were electrically stimulated at different locations on the wrist in a bipolar fashion. The evoked compound sensory nerve action potentials (CSNAPs) were recorded at the index finger. Electrical stimuli consisted of constant-current monophasic rectangular pulses. Initially, the nerve was stimulated with a cathodal current and a just supramaximal CSNAP was obtained. Then, at the same stimulus location, the nerve was excited with an anodal current. A just supramaximal response in the anodal-CSNAP was obtained, or until a maximum current of 100 mA was delivered. CSNAPs obtained from anodal excitation required several times more electrical stimulus intensity when compared to those derived from cathodal stimulation. Morphologically, they were similar, except the onset latency of the anodal-CSNAPs was approximately 0.2 to 0.3 msec early compared to that derived from cathodal stimulation. This implies that during anodal excitation, the site of nerve depolarization was not located underneath the anode, but was situated at some distance from it. Also, it appears that a minimum nerve length (10 mm or more) should be exposed to the anodal current in order to induce depolarization. A very localized application of the anodal stimulus often failed to elicit nerve depolarization.

The development of a stroke clinical pathway: an experience in a medium-sized community hospital.

Patients with acute ischemic strokes were studied in a medium-sized community hospital in Mississippi. Studies were done before and after implementation of the stroke clinical care pathway with emphasis on the following clinical indicators: 1) performance of a brain CT scan, 2) the search for the etiology of the stroke, 3) whether the patient was treated emergently for hypertension, 4) the use of measures to prevent deep-vein thrombosis, and 5) prophylactic drug treatment against recurrent stroke after hospital discharge. Following application of the clinical pathway, there was a significant improvement in all the clinical indicators that were felt to require further attention and none had a setback. The length of hospital stay was decreased, and there was no significant increase in the hospital costs in the post-pathway study despite an increase in the number of diagnostic and therapeutic procedures performed. When applied properly, clinical pathways can effectively mobilize hospital resources, maximize quality of care, and at the same time minimize costs.

Chili protects against aspirin-induced gastroduodenal mucosal injury in humans.

Capsaicin, the pungent ingredient of chili, has a gastroprotective effect against experimental gastric mucosal injury in animals. Such an effect has not, however, been documented in humans to date. Eighteen healthy volunteers with normal index endoscopies underwent two studies four weeks apart. Each subject took 20 g chili orally with 200 ml water in one study and 200 ml water in another study. In each case this was followed half an hour later by 600 mg aspirin BP with 200 ml water. Endoscopy was repeated 6 hr later. Gastroduodenal mucosal damage was assessed by a previously validated scoring system. The median gastric injury score after chili was 1.5 compared to 4 in the control group (P < 0.05), demonstrating a gastroprotective effect of chili in human subjects.

Peliosis hepatis: a case report.

A 54-year-old man who presented with marked hepatomegaly and a liver scan suggestive of an infiltrative malignancy was found to have peliosis hepatis caused by androgenic steroids. A detailed and repeated drug history is necessary for making the correct diagnosis. Withdrawal of the offending drug is indicated and may result in reversal of this serious form of hepatic toxicity.

Clinical and ultrastructural studies in duodenal pseudomelanosis.

Nine patients with duodenal pseudomelanosis are described: seven had endstage renal failure while one other patient had undergone renal transplantation. Eight of the nine had been on oral iron supplements. The pigment stained positively with Perls' stain for iron in five patients, positively with the Masson-Fontana method normally used to identify melanin in one, and positively with both methods in three. Electron probe x-ray analysis of the pigment on samples from six patients showed iron to be present in all six, while sulphur was present in five. Varying sulphur content of the pigment in different patients could account for differences in histochemical characteristics. Iron was also shown in the duodenal biopsies of 34 of 48 uraemic patients on oral iron supplements, but was present in only 22 of 120 patients endoscoped for miscellaneous conditions (p less than 0.001). We postulate that the pigment of duodenal pseudomelanosis is derived from iron absorbed from the lumen.

Unilateral asterixis: case report and comments.

Asterixis is usually bilateral. Occasionally, it may appear unilaterally. Hemiasterixis following infarction of the contralateral midbrain and thalamus is described. Mechanisms of asterixis and brain lesions associated with its unilateral appearance are reviewed. The mesodiencephalon is frequently implicated by the lesion either directly or indirectly, suggesting the importance of this structure in posture regulation.