Gateless patterning of epitaxial graphene by local intercalation.

We present a technique to pattern the charge density of a large-area epitaxial graphene sheet locally without using metallic gates. Instead, local intercalation of the graphene-substrate interface can selectively be established in the vicinity of graphene edges or predefined voids. It provides changes of the work function of several hundred meV, corresponding to a conversion from n-type to p-type charge carriers. This assignment is supported by photoelectron spectroscopy, scanning tunneling microscopy, scanning electron microscopy and Hall effect measurements. The technique introduces materials contrast to a graphene sheet in a variety of geometries and thus allows for novel experiments and novel functionalities.

Effects of separated pair housing of female C57BL/6JRj mice on well-being.

In laboratory animal facilities, it is a common code of practice to house female mice in groups. However, some experimental conditions require to house them individually, even though social isolation may impair their well-being. Therefore, we introduced a separated pair housing system and investigated whether it can refine single housing of adult female C57BL/6JRj mice. Individually ventilated cages (IVC) were divided by perforated transparent walls to separate two mice within a cage. The cage divider allowed visual, acoustic, and olfactory contact between the mice but prevented interindividual body-contact or food sharing. Short- and long-term effects of the separated pair housing system on the well-being of the mice were compared with single and group housing using a range of behavioral and physiological parameters: Nest building behavior was assessed based on the complexity of nests, the burrowing performance was measured by the amount of food pellets removed from a bottle, and trait anxiety-related behavior was tested in the free exploratory paradigm. For the evaluation of the ease of handling, interaction with the experimenter's hand was monitored. Social interaction with unknown conspecifics and locomotor activity were investigated in a test arena. Moreover, body weight and stress hormone (metabolites) were measured in feces and hair. After the mice spent a day under the respective housing conditions, concentrations of fecal corticosterone metabolites were higher in separated pair-housed mice, and they built nests of a higher complexity when compared to single-housed mice. The latter effect was still observable eight weeks later. In week 8, separated pair-housed mice showed less locomotor activity in the social interaction arena compared to mice from the other housing systems, i.e., single and group housing. Regardless of the time of testing, pair housing improved the burrowing performance. Separated pair-housed mice were more difficult to catch than group-housed mice. Hair corticosterone, progesterone, and dehydroepiandrosterone concentrations changed with increasing age independently of the housing system. There were no effects of the housing systems on trait anxiety-related behavior in the free exploratory paradigm, voluntary interaction with the experimenter's hand, and body weight. Overall, the transfer to the separated pair housing system caused short-term stress responses in female C57BL/6JRj mice. Long-term effects of separated pair housing were ambiguous. On one hand, separated pair housing increased nesting and burrowing behavior and may therefore be beneficial compared to single housing. But on the other hand, locomotor activity decreased. The study underlined that the effects of the housing conditions on physiological and behavioral parameters should be considered when analyzing and reporting animal experiments.

The Convective Transport of Active Species in the Tropics (CONTRAST) Experiment.

The Convective Transport of Active Species in the Tropics (CONTRAST) experiment was conducted from Guam (13.5° N, 144.8° E) during January-February 2014. Using the NSF/NCAR Gulfstream V research aircraft, the experiment investigated the photochemical environment over the tropical western Pacific (TWP) warm pool, a region of massive deep convection and the major pathway for air to enter the stratosphere during Northern Hemisphere (NH) winter. The new observations provide a wealth of information for quantifying the influence of convection on the vertical distributions of active species. The airborne in situ measurements up to 15 km altitude fill a significant gap by characterizing the abundance and altitude variation of a wide suite of trace gases. These measurements, together with observations of dynamical and microphysical parameters, provide significant new data for constraining and evaluating global chemistry climate models. Measurements include precursor and product gas species of reactive halogen compounds that impact ozone in the upper troposphere/lower stratosphere. High accuracy, in-situ measurements of ozone obtained during CONTRAST quantify ozone concentration profiles in the UT, where previous observations from balloon-borne ozonesondes were often near or below the limit of detection. CONTRAST was one of the three coordinated experiments to observe the TWP during January-February 2014. Together, CONTRAST, ATTREX and CAST, using complementary capabilities of the three aircraft platforms as well as ground-based instrumentation, provide a comprehensive quantification of the regional distribution and vertical structure of natural and pollutant trace gases in the TWP during NH winter, from the oceanic boundary to the lower stratosphere.

[Studies of hepatobiliary function with a scintillation camera and electronic data processing)]. / Zur Utersuchung der Hepatobiliären Funktion mit einer Szintillationskamera und elektronischer Datenverarbeitung

The authors performed the sequential scintigraphy after intravenous application of 131I-BSP using the scintillation camera. During the first 60 minutes the pictures of the liver and of the mesogastrium were recorded in one-minute intervals on the digital magnetic tape. The following scintigrams were then recorded after 3 and 24 hours after the injection. Choosing the region of interest the authors noted the histograms above the liver and above the mesogastrium, evaluated then the proportion of impulse rate above the liver and mesogastrium in measured intervals and obtained using the digital computer the velocity coefficient of the radioactivity accumulation in the liver as liver chromoexcretive function parameter. The results were compared with the standard test of the 45-minutes retention of the BSP, with the analysis of the curve measured above the temporal region, with the clinical status as well as with the results of other auxiliary examination methods. According to the first experiences gained when examining 91 individuals the described method proves to be very useful.

[Patient-controlled analgesia (PCA) for postoperative pain relief. A prospective observational study for evaluating the technology in a ward routine]. / Patientenkontrollierte Analgesie (PCA) zur postoperativen Schmerztherapie. Eine prospektive Beobachtungsstudie zur Technologiebewertung im Stationsbetrieb.

Patient-controlled analgesia (PCA) is rarely used on surgical wards despite described advantages of this method as compared to conventional techniques. Uncertainties in patient selection and insufficient evaluation of this technique may explain these circumstances. The aim of our study was to evaluate PCA on general surgery and traumatology wards by means of standardized criteria for technology assessment (i.e. safety, practicability, benefit for patients and medical staff) and the efficacy of pain relief. In a prospective study we investigated 120 patients. In phase I, we performed analgesic therapy with tramadol/metamizol (50 ASA status I-IV patients). In phase II, piritramid had been applied to 70 ASA status I-II patients after an intermediate analysis of phase I. In 7% of the patients technical problems led to an early interruption even at the end of the study period. There were, however, no incidents which caused vital problems for the patients. A mean postoperative pain level of 55 visual analogue scale points (0-100 point scale) was achieved with tramadol/metamizol. PCA was stopped in 16% of the patients due to the occurrence of nausea or vomiting and in two patients due to insufficient pain relief. The use of piritramid in phase II led to lower pain levels and no interruptions of PCA because of ineffectivity or nausea/vomiting.(ABSTRACT TRUNCATED AT 250 WORDS)

[Patient-controlled analgesia with piritramide for postoperative pain relief in general surgery: a prospective observational study.]. / Postoperative On-demand-Analgesie mit Piritramid in der Allgemeinchirurgie : Eine prospektive Beobachtungsstudie.

UNLABELLED: Many studies investigated patient-controlled analgesia (PCA) in the postoperative period in recovery rooms under anaesthesiologic monitoring but reports on the advantages and indications of PCA in surgical wards are scarce. The aim of this prospective study therefore was to investigate PCA as a routine technique in surgical wards. In particular we were interested in safety and in the efficacy of analgesia. PATIENTS AND METHODS: Subjects were 50 patients (ASA status I-II) recovering from surgery (thyroidectomy, herniotomy, anorectal surgery). All patients gave their informed consent. The pump used was the Injektomat CP PACOMR (Fresenius, Bad Homburg), and PCA was performed with piritramide. The demand dose was set at 2 mg, with a pump refractory time of 5 min between valid demands and a 24-h maximum of 60 mg. There was no continuous analgesic infusion. Standardized monitoring was carried out with measurement of blood pressure, pulse and respiratory rate. The intensity of pain was measured with a 100-point visual analogue scale at rest and during movement on the day before the operation and twice daily after the operation up to the day of discharge. Complications, side-effects and the degree of satisfaction experienced by the patients and the nurses were recorded with the aid of standardized questionnaires. RESULTS: The mean duration of the PCA period was 18.00+/-6.2 h (mean+/-standard deviation), and 8.5+/-7.9 demands per patient were recorded. The mean individual consumption of piritramide was 14.2+/-11.2 mg, i.e. 12mug.kg(-1).h(-1). The mean retrospective pain score was 2.4+/-1.3 on a 6-point verbal scale. The highest mean intensity of pain measured during movement was 37 points on the 100-point scale on the evening of the day of operation. The most frequent complaint during the PCA period was sedation, which occurred in 20 patients (40%). PCA was judged superior by 82% of patients when compared with previously experienced postoperative analgesia; 41 patients (82%) and 40 nurses (80%) judged PCA as good or excellent; 46 patients (92%) would prefer to receive PCA in the future. No incident led to a vital problem for the patients. PCA was stopped because of a respiratory rate of 9/min in one patient and because of systolic blood pressure <90 mmHg in another patient. Both patients were free of symptoms and subsequently made uneventful progress. CONCLUSIONS: We conclude that PCA with piritramide is a safe technique when performed under routine conditions on surgical wards. However, standardized monitoring is mandatory. PCA leads to effective analgesia and consequently to greater comfort of surgical patients in the postoperative period. These conclusions hold only for patients with ASA status I-II who have undergone operations of the types listed above.

Preincisional local anesthesia with bupivacaine and pain after laparoscopic cholecystectomy. A double-blind randomized clinical trial.

The aim of this study was to investigate whether local anesthesia of abdominal wall wounds prior to laparoscopic cholecystectomy leads to decreased pain beyond the immediate postoperative period and thus improves the comfort of the patient. In a randomized, double-blind study 50 patients scheduled for laparoscopic cholecystectomy were divided into two groups. In one group (n = 25) the skin, subcutis, fascia, muscle, and preperitoneal space were infiltrated with 8 ml of bupivacaine 0.5% 5 min before each abdominal wall incision. The control group (n = 25) received normal saline. The intensity of pain was assessed by a 100-point visual analogue scale (VAS) at rest and during movement and by the consumption of analgesics. Analgesic therapy was provided by on-demand analgesia with piritramide intravenously for 24 h and continued by ibuprofen orally on request. The mean intensity of pain at rest and during movement was lower but not statistically significant in patients who received bupivacaine compared to the control group up to the second postoperative day. The difference was between 4 and 9 VAS points and therefore of doubtful clinical relevance. Similar statistically nonsignificant results were found for the mean consumption of piritramide up to 16 h after the operation. Three patients (12%) in the bupivacaine group localized the most severe pain up to the second postoperative day to the right lower abdominal wall wound where the gallbladder had been extracted compared to 11 patients (44%) of the control group (P = 0.012). These results indicate that bupivacaine was effective at the site where it was administered.(ABSTRACT TRUNCATED AT 250 WORDS)

Novel current-conducting composite substrates for exposing osteoblasts to alternating current stimulation.

The present study demonstrates that novel nanocomposites consisting of blends of polylactic acid and carbon nanotubes effectively can be used to expose cells to electrical stimulation. When osteoblasts cultured on the surfaces of these nanocomposites were exposed to electric stimulation (10 microA at 10 Hz) for 6 h/day for various periods of time, there was a 46% increase in cell proliferation after 2 days, a 307% increase in the concentration of extracellular calcium after 21 consecutive days, and upregulation of mRNA expression for collagen type-I after both 1 and 21 consecutive days. These results provide evidence that electrical stimulation delivered through novel, current-conducting polymer/nanophase composites promotes osteoblast functions that are responsible for the chemical composition of the organic and inorganic phases of bone. Furthermore, this evidence elucidates aspects of the cellular/molecular-level mechanisms involved in new bone formation under electrical stimulation.