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Measuring the anisotropy of the field‐effect mobility provides insight into the correlation between molecular packing and charge transport in organic semiconductor materials. Single‐crystal field‐effect transistors are ideal tools to study intrinsic charge transport because of their high crystalline order and chemical purity. The anisotropy of the field effect mobility in organic single crystals has previously been studied by lamination of macroscopically large single crystals onto device substrates. Here, a technique is presented that allows probing of the mobility anisotropy even though only small crystals are available. Crystals of a soluble oligothiophene derivative are grown in bromobenzene and drop‐cast onto substrates containing arrays of bottom‐contact gold electrodes. Mobility anisotropy curves are recorded by measuring numerous single crystal transistor devices. Surprisingly, two mobility maxima occur at azimuths corresponding to both axes of the rectangular cyclohexyl‐substituted quaterthiophene (CH4T) in‐plane unit cell, in contrast to the expected tensorial behavior of the field effect mobility.

Fluorene-thiophene oligomers show great promise as the active material in p-type organic thin film transistors (TFTs) because of their good performance and good stability under ambient conditions. In this study, a series of fluorene-thiophene co-oligomers were asymmetrically substituted with an alkyl group to probe the effect chemical structure has on their thin film properties. The alkyl groups are n-hexyl, n-octyl, and n-dodecyl, respectively. These oligomers were characterized by elemental analysis, mass spectrometry, differential scanning calorimetry, and thermogravimetric analysis, whereas the thin films of these oligomers were characterized by X-ray diffraction, atomic force microscopy, and field-effect transistor measurements. We found that the performance of these asymmetric molecules is similar to their symmetric counterparts. Mobilities as high as 0.16 cm2V-1s-1were found for the n-dodecyl-substituted oligomer.

Alpha2-adrenoceptor-mediated vasoconstriction in the porcine palmar lateral vein is dependent upon activation of the extracellular signal-regulated kinase-mitogen-activated protein (ERK-MAP) kinase signal transduction pathway. Recent studies have shown that alpha2-adrenoceptor-mediated vasoconstriction in the rat aorta is also dependent upon activation of Rho kinase. The aim of this study was to determine whether Rho kinase and ERK-MAP kinase are part of the same signaling pathway. The Rho kinase inhibitor Y27632 (trans-4-[(1R)-1-aminoethyl]-N-4-pyridinylcyclohexanecarboxamide dihydrochloride) (10 microM) almost completely inhibited the contractile response to the alpha2-adrenoceptor agonist UK14304 (5-bromo-6-[2-imidazolin-2-ylamine]-quinoxaline bitartrate) in segments of porcine palmar lateral vein [maximum response 2.9 +/- 2.3% of 60 mM KCl response (mean +/- S.E.M.) in the presence of Y27632, compared with 64.9 +/- 7.1% in control tissues, n = 4]. However, Y27632 had no effect on alpha2-adrenoceptor-mediated ERK activation, as measured by Western blotting. Alpha2-adrenoceptor-mediated vasoconstriction was associated with an increase in phosphorylation of the myosin phosphatase-targeting subunit (MYPT) at Thr696 (the Rho kinase phosphorylation site). This phosphorylation was inhibited by 10 microM Y27632. In contrast, inhibition of ERK activation with the MAP kinase kinase inhibitor PD98059 (2-amino-3-methoxyflavone) (50 microM) had no effect on MYPT phosphorylation. Both Y27632 and PD98059 inhibited myosin light chain phosphorylation. These data indicate that alpha2-adrenoceptor-mediated vasoconstriction in the porcine palmar lateral vein is dependent upon both Rho kinase and ERK activation, although these are separate pathways. Rho kinase causes vasoconstriction through inhibition of myosin phosphatase and an increase in myosin light chain phosphorylation, whereas ERK causes vasoconstriction through a myosin phosphatase-independent pathway.

OBJECTIVES: To investigate trends in the incidence of acute pancreatitis resulting in admission to hospital, and mortality after admission, from 1963 to 1998. DESIGN: Analysis of hospital inpatient statistics for acute pancreatitis, linked to data from death certificates. SETTING: Southern England. SUBJECTS: 5312 people admitted to hospital with acute pancreatitis. MAIN OUTCOME MEASURES: Incidence rates for admission to hospital, case fatality rates at 0-29 and 30-364 days after admission, and standardised mortality ratios at monthly intervals up to one year after admission. RESULTS: The incidence of acute pancreatitis with admission to hospital increased from 1963-98: age standardised incidence rates were 4.9 per 100,000 population in 1963-74, 7.7 in 1975-86, and 9.8 in 1987-98. Age standardised case fatality rates within 30 days of admission were 14.2% in 1963-74, 7.6% in 1975-86, and 6.7% in 1987-98. From 1975-98, standardised mortality ratios at 30 days were 30 in men and 31 in women (compared with the general population of equivalent age in the same period = 1), and they remained significantly increased until month 5 for men and month 6 for women. CONCLUSIONS: Incidence rates for acute pancreatitis with admission to hospital rose in both men and women from 1963 to 1998, particularly among younger age groups. This probably reflects, at least in part, an increase in alcoholic pancreatitis. Mortality after admission has not declined since the 1970s. This presumably reflects the fact that no major innovations in the treatment of acute pancreatitis have been introduced. Pancreatitis remains a disease with a poor prognosis during the acute phase.

OBJECTIVES: To investigate time trends in mortality after admission to hospital for fractured neck of femur from 1968 to 1998, and to report on the effects of demographic factors on mortality. DESIGN: Analysis of hospital inpatient statistics for fractured neck of femur, incorporating linkage to death certificates. SETTING: Four counties in southern England. SUBJECTS: 32 590 people aged 65 years or over admitted to hospital with fractured neck of femur between 1968 and 1998. MAIN OUTCOME MEASURES: Case fatality rates at 30, 90, and 365 days after admission, and standardised mortality ratios at monthly intervals up to one year after admission. RESULTS: Case fatality rates declined between the 1960s and the early 1980s, but there was no appreciable fall thereafter. They increased sharply with increasing age: for example, fatality rates at 30 days in 1984-98 increased from 4% in men aged 64-69 years to 31% in those aged > or = 90. They were higher in men than women, and in social classes IV and V than in classes I and II. In the first month after fracture, standardised mortality ratios in women were 16 times higher, and those in men 12 times higher, than mortality in the same age group in the general population. CONCLUSIONS: The high mortality rates, and the fact that they have not fallen over the past 20 years, reinforce the need for measures to prevent osteoporosis and falls and their consequences in elderly people. Whether post-fracture mortality has fallen to an irreducible minimum, or whether further decline is possible, is unclear.

Seratrodast (ABT-001, AA-2414) undergoes cytochrome P450 (CYP)-dependent metabolism to a major (5-methylhydroxy seratrodast; 5-HOS) and a minor 4'-hydroxy seratrodast metabolite in human liver microsomes. The mean apparent K(m) and Vmax for the formation of 5-HOS were 15.5 microM and 589.0 pmol 5-HOS formed/mg protein/min, respectively. Chemical inhibition using isoform-selective CYP inhibitors, correlation of 5-HOS formation with several isoform-specific CYP activities in a panel of liver microsomes, metabolism by microsomes derived from CYP cDNA-expressed B-lymphoblastoid cells, and immunoinhibition by isoform-specific anti-CYP antibodies indicated that 5-HOS formation is catalyzed by CYP3A and CYP2C9/10, with a minor contribution from CYP2C8 and CYP2C19. At clinically relevant concentrations, seratrodast was found to inhibit tolbutamide methylhydroxylation (IC50 = 60 microM), (S)-mephenytoin 4'-hydroxylation (IC50 = 50 microM), and coumarin 7-hydroxylation (IC60 = 95 microM), indicating the potential for significant clinical interactions. The inducers of CYP3A and/or CYP2C9 (e.g. rifampicin and phenytoin) are likely to alter the disposition of seratrodast.

ObjectivesInclusion body myositis (IBM) shares some histopathological features with polymyositis (PM). Current investigations have low sensitivity for identification of amyloid deposits that are characteristic of IBM, contributing to frequent misdiagnosis. We compared muscle amyloid content, quantified using a novel positron emission tomography (PET) technique, in IBM and PM.MethodsTen cases with IBM and six controls with PM underwent clinical review, [18F]florbetapir PET/computed tomography, and magnetic resonance imaging (MRI) of whole-body skeletal musculature. [18F]florbetapir standardised uptake value ratios (SUVRs, reference=lumbar fat pad) in skeletal muscle were compared between cases and controls. The relationship in IBM of [18F]florbetapir SUVRs to clinical and MRI-derived measures of disease severity were also investigated.Results[18F]florbetapir SUVRs were significantly higher in those with IBM for all muscle regions assessed (total SUVR 1.45 [IQR 1.28–2.05] versus 1.01 [IQR 0.80–1.22], p=0.005). Strong negative correlation between MRI-derived muscle inflammation levels and [18F]florbetapir SUVRs were observed only in calf muscles bilaterally (right −0.73, p=0.02; left −0.68, p=0.03). No significant relationship between [18F]florbetapir SUVRs and clinical measures of disease severity were identified.ConclusionMuscle amyloid imaging using [18F]florbetapir PET may be useful in the diagnostic workup of IBM, particularly when differentiating from PM.

Osteoid osteoma is a benign bone tumor, which represents approximately 10% of all benign bone tumors. When localized to the carpus, osteoid osteomas are most often seen in the scaphoid and capitate. Rarely, these tumors can also be observed in the trapezium. Given the infrequency with which osteomas are located in the trapezium and often nonspecific presenting symptoms, diagnosis of this tumor can be challenging and requires a high index of suspicion.

Focuses on the major developments occurring across the entire range of categories for the vertical and short takeoff and landing (V/STOL) aircraft in 1999. Information on the Joint Strike Fighter program; Maiden flight of Boeing-Sikorsky RAH-66 Comanche Prototype No. 2 on March 30, 1999; Civil tilt-rotor research at the National Aeronautics and Space Administration; Programs at the National Rotorcraft Technology Center.

A practical synthesis of nicotinamide mononucleotide (β-NMN) and a high yield coupling with AMP-morpholidate that also provides NAD+ in an efficient manner are reported.

Deals with the developments in aircraft technology and operations in the United States. Achievements of Boeing-Sikorsky's RAH-66 program; Capabilities of Prototype One of Boeing-Sikorsky; Information on V-22 Osprey flight testing program; Focus of study of the National Aeronautics and Space Administration on primary flight displays for the Civil Tiltrotor program.

Gives information on the schedule of the flights of the Joint Strike Flighter concept demonstrator aircraft (CDA). How the CDA will be powered; Information on tests of model-scale rotors conducted by Boeing Helicopters (Philadelphia); Details on a demonstration of landing gear on a helicopter configuration by the Army.

The present work is a study of multivalued functions and measures which have many applications to mathematical economics and control problems. Both have received considerable attention in recent years. We study the set of selectors of the space of all p- integrable, X- valued additive set functions. This space contains an isometrically imbedded copy of Lp(X).

Several letters to the editor related to various issues including the usage of word-processing computers by the editor, and Kate O'Beirne's column published in the previous issue of the journal are presented.