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Organic–metal interfaces are of vital importance for regulating the optoelectronic properties of devices in molecular electronics. Interactions within the metal–adsorbate system influence the photonic performance through perturbations of the electronic structure. Such changes and associated interfacial charge transfer are directly influenced by how the organic molecule structurally adsorbs to the substrate. Herein, we use a combination of surface-enhanced Raman scattering (SERS) spectroscopy and dispersion-corrected density functional theory (DFT-D) to show that 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-Pc) adsorbs through both physisorption and chemisorption on a gold surface with the TIPS-Pc adopting an adsorption geometry with the pentacene backbone oriented parallel to the substrate. When chemisorbed, our results provide direct evidence of Au–C bond formation within the ethynyl moieties. Most importantly, we demonstrate that the electronic structure of the resulting TIPS-Pc surface system is distinctly dependent on the adsorption mechanism. These results show new evidence of chemisorption routes for TIPS-Pc on metal surfaces and illustrate the importance of understanding the interfacial structure at the molecular level for dictating and assessing the performance of molecular optoelectronic devices.

The subsurface rock beneath the ocean is one of the largest biospheres on Earth, and microorganisms within influence global-scale nutrient cycles. This biosphere is difficult to study, in part due to the low concentrations of microorganisms that inhabit the vast volume of the marine lithosphere.

Abstract: Inositol has been cited as being essential for the growth of micro-organisms and animals. Its action rests mostly in the formation of a set of inositol-containing lipids, including phosphatidylinositol and its phosphorylated derivatives. To evaluate the functional responses coupled to the phosphoinositide metabolism in Trypanosoma cruzi we used myo-inositol and its six fluorinated analogues. Their uptake into epimastigotes was characterised using tritium-labeled myo-inositol and monodeoxyfluoro-myo-inositols. The analogues were tested for their ability to inhibit [3H]-myo-inositol incorporation into phosphoinositides and the proliferation of epimastigotes and amastigotes. The results showed differences between T. cruzi and mammalian systems in the responses to the fluorinated analogues. We found that the 3-, 5- and 6-fluoro analogues did not enter the cells but had an inhibitory effect on the incorporation of the radioactive inositol into lipids and on the amastigotes' and epimastigotes' replication. The most effective inhibitor, 1-D-6-deoxy-6-myo-inositol, had no effect on mammalian cell division.

In 1979, the National Cancer Institute in Bethesda, Maryland initiated a randomized, prospective trial to compare surgery versus radiation therapy in the treatment of stages I and II breast cancer. Surgical treatment consists of total mastectomy with axillary lymph node dissection (modified radical mastectomy) and breast reconstruction; radiation treatment consists of gross tumor excision, axillary lymph node dissection, and comprehensive irradiation including a boost dose to the tumor bed. All patients with pathologically positive axillary nodes receive 11 cycles of adjuvant Adriamycin®/Cytoxan® chemotherapy. As of December 1984, there have been 175 patients entered in the study. Twenty-three patients have developed disease recurrence (12 mastectomy, 11 radiation), but it is too early to obtain definitive treatment-related results.

The radial artery was proposed and then abandoned as a coronary artery bypass graft in the 1970s. Development of new pharmacologic antispasmodic agents and minimally traumatic harvesting techniques has led to a revival of the use of the radial artery in coronary artery bypass procedures. Unlike the saphenous vein in the lower extremities, the radial artery in the volar forearm is not a subcutaneous structure. Safe harvest of the artery requires an understanding of volar forearm anatomy. Based on review of anatomy, cadaver dissection, and clinical experience with 40 patients, we have developed a technique for radial artery harvest. The volar forearm is divided into three zones: the proximal zone, the middle zone, and the distal zone. In each zone, important anatomic landmarks are identified. Our harvesting technique has resulted in minimal postoperative morbidity and no postoperative ischemic complications. Although the pedicled internal thoracic artery graft remains the primary arterial conduit for myocardial revascularization, the radial artery is an excellent additional bypass conduit.

The voltage across the cell membrane of human T-lymphocyte cell lines was recorded by the whole cell patch clamp technique. We studied how this voltage fluctuated in time and found that these fluctuations have fractal characteristics. We used the Hurst rescaled range analysis and the power spectrum of the increments of the voltage (sampled at 0.01-sec intervals) to characterize the time correlations in these voltage fluctuations. Although there was great variability in the shape of these fluctuations from different cells, they all could be represented by the same fractal form. This form displayed two different regimes. At short lags, the Hurst exponentH=0.76±0.05 (SD) and, at long lags,H=0.26±0.04 (SD). This finding indicated that, over short time intervals, the correlations were persistent (H>0.5), that is, increases in the membrane voltage were more likely to be followed by additional increases. However, over long time intervals, the correlations were antipersistent (H<0.5), that is, increases in the membrane voltage were more likely to be followed by voltage decreases. Within each time regime, the increments in the fluctuations had characteristics that were consistent with those of fractional Gaussian noise (fGn), and the membrane voltage as a function of time had characteristics that were consistent with those of fractional Brownian motion (fBm).

After their axons have been severed, nerve cells can achieve functional recovery either by regrowth of the injured cells or by direct repair of the injured cell at the site of injury. Direct repair of a severed axon promises the advantages of preserving the viability and existing connections of the axon distal to the injury. We report here the first successful axon reconnection in the earthworm (Lumbricus terrestris) medial giant axon (MGA) in vitrosystem (1) by the application of well-focused 15 nsec, 5 to 50 μJ/pulse, 308 nm laser pulses. Axon reconnection is documented by light and electron microscopy, as well as by transfer of the iontophoretically injected fluorescent dye, Lucifer Yellow, across the reconnected MGA segments.

In 1979, the National Cancer Institute in Bethesda, Maryland initiated a randomized, prospective trial to compare surgery versus radiation therapy in the treatment of stages I and II breast cancer. Surgical treatment consists of total mastectomy with axillary lymph node dissection (modified radical mastectomy) and breast reconstruction; radiation treatment consists of gross tumor excision, axillary lymph node dissection, and comprehensive irradiation including a boost dose to the tumor bed. All patients with pathologically positive axillary nodes receive 11 cycles of adjuvant Adriamycin®/Cytoxan®chemotherapy. As of December 1984, there have been 175 patients entered in the study. Twenty-three patients have developed disease recurrence (12 mastectomy, 11 radiation), but it is too early to obtain definitive treatment-related results. En 1979 l'Institut National du Cancer de Bethesda a lancé une étude prospective randomisée permettant de comparer les résultats respectifs de la chirurgie et de la radiothérapie en ce qui concerne les stades I et II du cancer du sein. Le traitement chirurgical consiste en la mastectomie totale complétée par le curage ganglionnaire axillaire (mastectomie totale modifiée); le traitement dit radiothérapique consiste en l'exérèse large de la tumeur associée au curage ganglionnaire axillaire et à l'administration d'une dose élevée de rayons au niveau du lit tumoral. Toutes les opérées dont les ganglions sont envahis reçoivent en outre 11 cycles d'une combinaison d'Adriamycine et Cytoxan. De 1979 à Décembre 1984, 175 malades ont fait l'objet de cette étude. Vingt-trois ont accusé une récidive (12 après mastectomie et 11 après traitement dit radiothérapique) mais il est encore trop tôt pour tirer des conclusions définitives de ces résultats. El Instituto Nacional de Cáncer de Bethesda inició en 1979 un ensayo prospectivo y aleatorio orientado a comparar el tratamiento quirúrgico versus radioterapia en el manejo del cáncer mamario en estados I y II. El tratamiento quirúrgico consistió de mastectomía total con disección ganglionar axilar (mastectomía radical modificada) y reconstrucción mamaria; el manejo radioterapéutico consistió de resección del tumor, disección de los ganglios linfáticos axilares e irradiación comprensiva incluyendo una dosis de refuerzo al lecho tumoral. Todos los pacientes con ganglios axilares histológicamente positivos recibieron 11 ciclos de quimioterapia adyuvante con Adriamicina/Citoxán. Hasta diciembre de 1984, 175 pacientes habían entrado al estudio. Veintitrés pacientes han desarrollado recurrencia de la enfermedad (12 mastectomía, 11 irradiación), pero es todavía muy temprano para derivar resultados definitivos.

Of 206 leprosy patients, 40% (82) were found to have reactive nontreponemal tests for syphilis. Forty percent of these patients (33 of 82) were found to have reactive treponemal tests, either fluorescent treponemal antibody absorption test (FTA-ABS), Treponema pallidum immobilization test (TPI), or both. It was concluded that at least 16% of the leprosy patients studied had some serologic evidence suggestive of a treponemal infection either in the past or at present. Treponemal diseases may be common among leprosy patients, and may account for some of the reactive serologic tests usually called biologic false positive BFP. The FTA-ABS test was found to be more frequently reactive than the TPI among those leprosy patients studied. The rapid plasma reagin (RPR) card test was rather insensitive but seemed more specific than the venereal disease research laboratory test for syphilis (VDRL). Question of false-positive FTA-ABS tests in some of these patients could be neither established nor disproved.