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We have developed a handheld $\gamma $ -ray spectrometer based on 1024 pixels, $2.8\,\,\text {mm} \times 2.8\,\,\text {mm} \times 6$ mm in size, of gadolinium–yttrium–gallium–aluminum garnet (GYGAG) ((Gd,Y,Ce)3(Ga,Al)5O12) ceramic scintillator (total of 48-cm3 detector volume) coupled to silicon photodiode (SiPD) arrays. The SiPD arrays and readout ASIC, originally developed for medical imaging applications, have been adapted for portability in a lightweight box with heatsink and thermoelectric cooling. Custom readout firmware for $\gamma $ -ray spectroscopy has been implemented, and a system user interface was developed that runs on an Android tablet. We have optimized the processing of the GYGAG(Ce), the pixel optical coupling, and electronics readout parameters to obtain single pixel energy resolution as good as $R (662\,\,\text {keV}) = 3.1$ % full-width at half-maximum and full device resolution with singles events from all pixels summed of 4.5%. When Compton-summed events are included, full-energy peak efficiency increases by $\sim 2\times $ , and $R (662\,\,\text {keV}) = 4.7$ % is obtained for the full device. The pixelated architecture is leveraged to locate point sources of radiological materials using Compton imaging and active masking techniques. Directional detection of a 1 mCi Cs-137 source at 10 m can be made to ±10° in ~2 s.

NeutronSTARS ( Neutron - S ilicon T elescope A rray for R eaction S tudies) consists of 2.2-tons of gadolinium-doped liquid scintillator for neutron detection and large area silicon detectors for charged particle identification. This detector array is intended for low-energy-nuclear-reaction measurements that result in the emission of neutrons such as ( n , x n ) and fission. This paper describes the NeutronSTARS experimental setup, calibration, and the array’s response to neutral and charged particles.

Hyperion is a new high-efficiency charged-particle γ -ray detector array which consists of a segmented silicon telescope for charged-particle detection and up to fourteen high-purity germanium clover detectors for the detection of coincident γ rays. The array will be used in nuclear physics measurements and Stockpile Stewardship studies and replaces the STARLiTeR array. This article discusses the features of the array and presents data collected with the array in the commissioning experiment.

Gadolinium Garnet transparent ceramics doped with Ce, ((Gd,Y,Ce)3(Ga,Al)5O12), for gamma-ray spectroscopy provide high density, high light yield, high energy resolution , high Z, mechanical robustness, and they are unreactive to air and water. Gadolinium garnet single crystals are costly to grow, due to their high melting points, and suffer from non-uniform light yield, due to Ce segregation. In contrast, transparent polycrystalline ceramic Garnets are never melted, and therefore are less costly to produce and provide the uniform light yield required to achieve high energy resolution with a scintillator. GYGAG(Ce) transparent ceramics offer energy resolution as good as R(662 keV) = 3.5%, in a pixelated detector utilizing Silicon photodiode array readout. We have developed a modular handheld detector based on pixelated GYGAG(Ce) on a photodiode array, that offers directional detection for point source detection as well as gamma spectroscopy. Individual modules can be assembled into detectors ranging from pocket-size to large panels, for a range of applications. Large GYGAG(Ce) transparent ceramics in the 2-5 in3 size range have been fabricated at LLNL. Instrumentation of these ceramics with Silicon photomultipliers (SiPMs) and super bi-alkali PMTs has been explored and energy resolution as good as R(662 keV) = 5% has been obtained. Further improvements with SiPM readout will leverage their high quantum efficiency in the 500-650 nm range where GYGAG(Ce) emits, and implement electronics that minimize the effect of SiPM dark current and capacitance on the pulse height spectra. This work was performed under the auspices of the U.S. DOE by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, and has been supported by the US Department of Homeland Security, Domestic Nuclear Detection Office, under competitively awarded IAA HSHQDC-12-X-00149 under Contract No. DE-AC03-76SF00098. LLNL-ABS-724480.

New transparent ceramic scintillators offer advantages for applications in gamma spectroscopy and X-ray imaging. For gamma spectroscopy, excellent light yield, material uniformity, light yield proportionality, mechanical and environmental ruggedness can be achieved in polycrystalline ceramic oxide garnets. We have fabricated 5 in3 Ce-doped Gd garnet transparent ceramics. GYGAG(Ce) garnet transparent ceramics offer $^{\mathbf {\rho \, =\, 5.8g/cm^{3},\,}}$, $z_{eff}=48$, principal decay of 2 O 3 structure structure. The 12” x 12” GLO imaging plates outperform scintillator glass for MeV radiography, due to higher light yield (55,000 Ph/MeV) and better stopping, while providing spatial resolution of >8 lp/mm for MeV X-rays.

Eu-doped strontium iodide single crystal growth has reached maturity and prototype SrI2(Eu)-based gamma ray spectrometers provide detection performance advantages over standard detectors. SrI2(Eu) offers a high, proportional light yield of >80,000 photons/MeV. Energy resolution of

Native and exotic plants can influence one another's fecundity through their influence on shared pollinators. Specifically, invasion may alter abundance and composition of local floral resources, affecting pollinator visitation and ultimately causing seedset of natives in more-invaded and less-invaded floral neighborhoods to differ. Such pollinator-mediated effects of exotic plants on natives are common, but native and exotic plants often share multiple pollinators, which may differ in their responses to altered floral neighborhoods. We quantified pollinator-mediated interactions between three common forbs of western Washington prairies (native Microseris laciniata and Eriophyllum lanatum and European Hypochaeris radicata) in three floral neighborhoods: 1) high native and low exotic floral density, 2) high exotic floral density and low native density, and 3) experimentally manipulated low exotic floral density. Pollinator visitation rates varied by floral neighborhood, plant species identity, and their interaction for all three plant species. Similarly, pollinator functional groups (eusocial bees, solitary bees, and syrphid flies) contributed differing proportions of total visitation to each species depending upon neighborhood context. Consequently, in exotic neighborhoods H. radicata competed with native M. laciniata, reducing seed set, while simultaneously facilitating visitation and seed set for native E. lanatum. Seed set of H. radicata was also highest in exotic neighborhoods (with high densities of conspecifics), raising the possibility of a positive feedback between exotic abundance and success. Our results suggest that the outcome of indirect interactions between native and exotic plants depends on the density and the composition of the floral neighborhood and of the pollinator fauna, and on context-dependent pollinator foraging.

Here, nuclear excitation by electronic transition (NEET) is a rare nuclear excitation that can occur in isotopes containing a low-lying nuclear excited state. Over the past 40 yr, several experiments have attempted to measure NEET of 235U and those experiments have yielded conflicting results.

Preparation of Pu and U targets on thin natural C (100 μg/cm2) and Ti (2 and 3 μm) substrates is described. The actinide material of interest was first purified using ion exchange chromatography to remove any matrix contaminants or decay products present in the parent stock solution. The actinide solution was prepared in 0.05 M HNO3 with a final aliquot volume not exceeding 100 μL for the deposition procedure. The electroplating cells were developed in-house and were primarily made of Teflon. The source material deposited ranged from 125 to 400 μg/cm2. It was determined that multiple layers of U and Pu were required to produce thicker targets on Ti. Plating efficiency was greatly affected by the cell volume, solution aliquot size, pre-treatment of the foils, solution mixing during plating, and the fit of the electrode contact with the target substrate. The final procedure used for deposition is described in detail.

Recent renewed emphasis placed on gamma-ray detectors for national security purposes has motivated researchers to identify and develop new scintillator materials capable of high energy resolution and growable to large sizes. We have discovered that SrI2(Eu) has many desirable properties for gamma-ray detection and spectroscopy, including high light yield of ∼90,000 photons/MeV and excellent light yield proportionality. We have measured

Recent genome wide association scans (GWAS) for reading and language abilities have pin-pointed promising new candidate loci. However, the potential contributions of these loci remain to be validated. In the present study, we tested 17 of the most significantly associated single nucleotide polymorphisms (SNPs) from these GWAS studies (p

We report on the development of two new mechanically rugged, high light yield transparent ceramic scintillators: (1) Ce-doped Gd-garnet for gamma spectroscopy, and (2) Eu-doped Gd-Lu-bixbyite for radiography. GYGAG(Ce) garnet transparent ceramics offer ρ = 5.8g/cm3, Zeff = 48, principal decay of 8 lp/mm.

Adult mouse ultrasonic vocalizations (USVs) occur in multiple behavioral and stimulus contexts associated with various levels of arousal, emotion and social interaction. Here, in three experiments of increasing stimulus intensity (water; female urine; male interacting with adult female), we tested the hypothesis that USVs of adult males express the strength of arousal and emotion via different USV parameters (18 parameters analyzed). Furthermore, we analyzed two mouse lines with heterozygous Foxp2 mutations (R552H missense, S321X nonsense), known to produce severe speech and language disorders in humans. These experiments allowed us to test whether intact Foxp2 function is necessary for developing full adult USV repertoires, and whether mutations of this gene influence instinctive vocal expressions based on arousal and emotion. The results suggest that USV calling rate characterizes the arousal level, while sound pressure and spectrotemporal call complexity (overtones/harmonics, type of frequency jumps) may provide indices of levels of positive emotion. The presence of Foxp2 mutations did not qualitatively affect the USVs; all USV types that were found in wild-type animals also occurred in heterozygous mutants. However, mice with Foxp2 mutations displayed quantitative differences in USVs as compared to wild-types, and these changes were context dependent. Compared to wild-type animals, heterozygous mutants emitted mainly longer and louder USVs at higher minimum frequencies with a higher occurrence rate of overtones/harmonics and complex frequency jump types. We discuss possible hypotheses about Foxp2 influence on emotional vocal expressions, which can be investigated in future experiments using selective knockdown of Foxp2 in specific brain circuits.

Development of the Europium-doped Strontium Iodide scintillator, SrI2(Eu2+), has progressed significantly in recent years. SrI2(Eu2+) has excellent material properties for gamma ray spectroscopy: high light yield (

Breakthrough energy resolution, R(662keV) < 4%, has been achieved with an oxide scintillator, Cerium-doped Gadolinium Yttrium Gallium Aluminum Garnet, or GYGAG(Ce). Transparent ceramic GYGAG(Ce), has a peak emission wavelength of 550 nm that is better matched to Silicon photodetectors than to standard PMTs. We are therefore developing a spectrometer based on pixelated GYGAG(Ce) on a Silicon photodiode array that can provide R(662 keV) = 3.6%. In comparison, with large 1-2 in3 size GYGAG(Ce) ceramics we obtain R(662 keV) = 4.6% with PMT readout. We find that ceramic GYGAG(Ce) of a given stoichiometric chemical composition can exhibit very different scintillation properties, depending on sintering conditions and post-anneal treatments. Among the characteristics of transparent ceramic garnet scintillators that can be controlled by fabrication conditions are: scintillation decay components and their amplitudes, intensity and duration of afterglow, thermoluminescence glow curve peak positions and amplitudes, integrated light yield, light yield non-proportionality - as measured in the Scintillator Light Yield Non-Proportionality Characterization Instrument (SLYNCI), and energy resolution for gamma spectroscopy. Garnet samples exhibiting a significant fraction of Cerium dopant in the tetravalent valence also exhibit: faster overall scintillation decay, very low afterglow, high light yield, but poor light yield proportionality and degraded energy resolution.

Crohn's disease (CD) and ulcerative colitis (UC) are idiopathic inflammatory bowel diseases (IBD) that are characterized by chronic intestinal inflammation and are associated with abnormalities of peripheral and mucosal immune function. The aim of our study was to determine whether CD or UC is characterized by discrete profiles of intestinal lymphokine production. Total cellular RNA was isolated from biopsies of healthy controls and from patients with IBD. Messenger RNA transcript levels in biopsies were determined for interleukin-2 (IL-2), IL-4, IL-5, and interferon-γ (IFN-γ), using a quantitative reverse transcriptase polymerase chain reaction method. Compared with inflamed UC mucosa and controls, CD mucosal lesions contained higher IL-2 and IFN-γ mRNA (p0.05), which is consistent with a T-helper cell 1 (Th1)-like pattern. In UC, IL-5 mRNA content was higher in involved areas compared with controls (p0.05) and inflamed CD lesions (p0.05), suggestive of a Th2 pattern. We conclude that the intestinal mucosa of CD and UC have inflammatory responses characterized by discrete T-helper profiles of lymphokines. This strongly suggests that the immunopathogenesis of these two forms of IBD are different.

We describe the Inverse Free Electron Accelerator currently under construction at Lawrence Livermore National Lab. Upon completion of this accelerator, high brightness electrons generated in the photoinjector blowout regime and accelerated to 50 MeV by S-band accelerating sections will interact with > 4 TW peak power Ti:Sapphire laser in a highly tapered 50 cm undulator and experience an acceleration gradient of > 200 MeV/m. We present the final design of the accelerator as well as the results of start-to-end simulations investigating preservation of beam quality and tolerances involved with this accelerator.

High energy resolution gamma-ray detectors that can be formed into relatively large sizes while operating at room temperature offer many advantages for national security applications. We are working toward that goal through the development of SrI 2 (Eu) scintillator detectors, which routinely provide 10 cm3. In this study, we have tested pure, undoped SrI 2 to gain a better understanding of the scintillation properties and spectroscopic performance achievable without activation. An undoped crystal grown from 99.999% pure SrI 2 pellets was tested for its spectroscopic performance, its light yield, and uniformity of scintillation light collection as a function of gamma-ray interaction position relative to the crystal growth direction. Undoped SrI 2 was found to provide energy resolution of 5.3% at 662 keV, and the light collection nonuniformity varied by only 0.72% over the length of the crystal. Measurements of both a 3% Eu-doped and the undoped SrI 2 crystal were carried out in the SLYNCI facility and indicate differences in their light yield non-proportionality. The surprisingly good scintillation properties of the pure SrI 2 crystal suggests that with high-purity feedstock, further reduction of the Eu concentration can be made to grow larger crystals while not adversely impacting the spectroscopic performance.

Recently discovered scintillators for gamma ray spectroscopy, single crystal SrI{sub 2}(Eu), GYGAG(Ce) transparent ceramic and Bismuth-loaded plastics, offer resolution and fabrication advantages compared to commercial scintillators, such as NaI(Tl) and standard PVT plastic. Energy resolution at 662 keV of 2.7% is obtained with SrI{sub 2}(Eu), while 4.5% is obtained with GYGAG(Ce). A new transparent ceramic scintillator for radiographic imaging systems, GLO(Eu) offers high light yield of 70,000 Photons/MeV, high stopping, and low radiation damage. Implementation of single crystal SrI{sub 2}(Eu), Gd-based transparent ceramics, and Bi-loaded plastic scintillators can advance the state-of-the art in ionizing radiation detection systems.

There is an ever increasing demand for gamma-ray detectors which can achieve good energy resolution, high detection efficiency, and room-temperature operation. We are working to address each of these requirements through the development of large volume SrI 2 (Eu) scintillator detectors. In this work, we have evaluated a variety of SrI 2 crystals with volumes >10 cm3. The goal of this research was to examine the causes of energy resolution degradation for larger detectors and to determine what can be done to mitigate these effects. Testing both packaged and unpackaged detectors, we have consistently achieved better resolution with the packaged detectors. Using a collimated gamma-ray source, it was determined that better energy resolution for the packaged detectors is correlated with better light collection uniformity. A number of packaged detectors were fabricated and tested and the best spectroscopic performance was achieved for a 3% Eu doped crystal with an energy resolution of 2.93% FWHM at 662keV. Simulations of SrI 2 (Eu) crystals were also performed to better understand the light transport physics in scintillators and are reported. This study has important implications for the development of SrI 2 (Eu) detectors for national security purposes.

We are developing new scintillator materials that offer potential for high resolution gamma ray spectroscopy at low cost. Single crystal SrI 2 (Eu) offers ∼3% resolution at 662 keV, in sizes of ∼1 in3. We have developed ceramics processing technology allowing us to achieve cubic inch scale transparent ceramic scintillators offering gamma spectroscopy performance superior to NaI(Tl). Our bismuth-loaded plastic scintillator demonstrates energy resolution of ∼8% at 662 keV, for samples of ∼0.5 cm3.

Transparent ceramics combine the scintillation performance of single crystals with the ruggedness and processability of glass. We have developed a versatile, scaleable fabrication method, wherein nanoparticle feedstock is consolidated at temperatures well below melting to form inch-scale phase-pure transparent ceramics with optical scatter of α

Biotin, essential for normal fetal growth and development, must be transported across the placenta to reach the fetus. This study evaluated placental transport of biotin using microvillous membrane vesicles (MMV), cultured trophoblasts, and isolated perfused cotyledon. Biotin uptake in MMV was stimulated by an inward Na+ gradient. In the presence of Na+, maximal stimulation was observed with Cl-, among various anions. Biotin uptake required 1 Na+ per biotin molecule. Kinetic analysis in MMV showed saturable transport with a Michaelis constant (Km) of 26.1 +/- 2.9 microM. Increases in membrane potential did not alter biotin uptake. Biotin uptake by cultured trophoblasts was also stimulated in the presence of Na+ and was saturable (Km = 7.0 +/- 1.5 microM). In the perfused placental cotyledon, maternal-to-fetal (M-to-F) biotin transfer was not saturable. However, biotin transfer in the M-to-F direction was significantly greater than the reverse. When the fetal circulation was closed to allow accumulation, an F/M ratio of only 1.056:1 was achieved. Tissue analysis of biotin contents suggested an active accumulation within the placental compartment. This study demonstrates that biotin is actively transported into the placenta, across the microvillous membrane, and released into the fetal compartment at a slower rate.

A Compton scattering {gamma}-ray source, capable of producing photons with energies ranging from 0.1 MeV to 0.9 MeV has been commissioned and characterized, and then used to perform nuclear resonance fluorescence (NRF) experiments. The performances of the two laser systems (one for electron production, one for scattering), the electron photoinjector, and the linear accelerator are also detailed, and {gamma}-ray results are presented. The key source parameters are the size (0.01 mm{sup 2}), horizontal and vertical divergence (6 x 10 mrad{sup 2}), duration (10 ps), spectrum and intensity (10{sup 5} photons/shot). These parameters are summarized by the peak brightness, 1.5 x 10{sup 15} photons/mm{sup 2}/mrad{sup 2}/s/0.1% bandwidth, measured at 478 keV. Additional measurements of the flux as a function of the timing difference between the drive laser pulse and the relativistic photo-electron bunch, {gamma}-ray beam profile, and background evaluations are presented. These results are systematically compared to theoretical models and computer simulations. NRF measurements performed on {sup 7}Li in LiH demonstrate the potential of Compton scattering photon sources to accurately detect isotopes in situ.

The behavior of vaporous hydrogen peroxide (VHP) was examined in clean, room-scale galvanized steel (GS) and polyvinylchloride-coated steel air ducts, to understand how it might be used to decontaminate larger ventilation systems. VHP injected into the GS duct decreased in concentration along the length of the duct, whereas VHP concentrations in the polyvinylchloride coated duct remained essentially constant, suggesting that VHP decomposed at the GS surface. However, decomposition was reduced at lower temperatures (approximately 22 degrees C) and higher flow rates (approximately 80 actual cubic meter per hour). A computational fluid dynamics model incorporating reactive transport was used to estimate surface VHP concentrations where bioaerosol contamination is likelyto reside, and also showed that VHP decomposition was enhanced at bends within the duct, compared to straight sections. Use of G. stearothermophilus indicators, in conjunction with model estimates, indicated that a concentration-contact time of approximately 100 mg/L H2O2(g) x min was required to achieve a 6 log reduction of indicator spores in clean GS duct, at 30 degrees C. When VHP is selected for building decontamination, this work suggests the most efficacious strategy may be to decontaminate GS ducting separately from the rest of the building, as opposed to a single decontamination event in which the ventilation system is used to distribute VHP throughout the entire building.

Ceramic and single crystal Lutetium Aluminum Garnet scintillators exhibit energy resolution with bialkali photomultiplier tube detection as good as 8.6% at 662 keV. Ceramic fabrication allows production of garnets that cannot easily be grown as single crystals, such as Gadolinium Aluminum Garnet and Terbium Aluminum Garnet. Measured scintillation light yields of Cerium-doped ceramic garnets indicate prospects for high energy resolution.

Objective The current optimal management of locally advanced rectal cancer has evolved from surgical excision followed by postoperative therapy in patients with involved margins, to an increasing use of a preoperative strategy to ‘down-stage and/or down-size’ the tumour. This treatment strategy is based on the relationship of the tumour to the mesorectal fascia, the optimal surgical circumferential resection margin that can be achieved by total mesorectal excision. We have reviewed the recent evidence for this strategy. Method An electronic literature search using PubMed identified articles on the subject of rectal cancer between January 2000 and December 2005. The search was limited to English language publications with secondary references obtained from key articles. Articles published in high impact factor journals formed the basis of the review, together with articles related to national programmes on the management of rectal cancer. This does lead to a selection bias, particularly as the articles identified had a European bias. Conclusion The UK NHS Cancer Plan has outlined the basis for the multidisciplinary team (MDT) management of rectal cancer. Advances in preoperative assessment through accurate staging and the recognition of the importance of the relationship of the tumour to the mesorectal fascia has allowed the selection of patients for a preoperative strategy to down-size/down-stage the tumour if this fascial layer is involved or threatened. Improvements in the quality of surgical resection through the acceptance of the principle of total mesorectal excision have ensured that optimal surgery remains the cornerstone to successful treatment. Further refinements of the MDT process strive to improve outcome. Accurate radiological staging, optimal surgery and detailed histopathological assessment together with consideration of a preoperative neoadjuvant strategy should now form the basis for current treatment and future research in rectal cancer.

The last 20 years have seen enormous strides forward in the treatment of rectal cancer with the development of improved surgical technique, tumour staging, histopathological audit and multidisciplinary team (MDT) management with emphasis on improving survival and reducing local recurrence rates. However, each rectal cancer discussed at the MDT meeting involves an individual patient. The quality of life for each patient must be taken into account when making treatment decisions, which sometimes may not fit with 'standard' treatment guidelines as the individual patient does not have a 'standard' tumour. For one patient with a tumour 5 cm above the anal verge, a low anterior resection may maintain quality of life with no incontinence and preservation of urinary and sexual function. For another with a tumour at the same level, preoperative chemo-radiotherapy may exacerbate mild incontinence and a low resection may result in a 'perineal stoma'. A decision to perform an abdomino-perineal excision (APE) must not be considered a failure of surgical treatment or be seen as a suboptimal centre by having a high APE rate. On the contrary, APE rates should represent sub-specialization and patient selection. Indeed, good function from a permanent stoma may be better than bad function from a poorly functioning coloanal pouch. Having improved tumour staging, surgical technique, oncological treatment and histopathological assessment, quality of life must not be forgotten. Both quality and quantity of life are important to all patients.

We report on an unprecedented infrared time series of spectra of V1187 Sco, a very fast ONeMg nova. The observations covered a 56 day period (2004 August 6-September 30) starting 2 days after the nova's peak brightness. Time evolution of the spectra revealed changing line strengths and profiles on timescales of less than a day to weeks as the nova evolved from early postmaximum to early coronal phases. When our ground-based optical and Spitzer Space Telescope data were combined, the wavelength coverage of 0.38-36 μm allowed an accurate spectral energy distribution to be derived when it was about 6 weeks after outburst. Developing double structure in the He I lines showed them changing from narrow to broad in only a few days. Using the O I lines in combination with the optical spectra, we derived a reddening of E(B - V) = 1.56 ± 0.08 and a distance of 4.9 ± 0.5 kpc. Modeling of the ejected material strongly suggested that it was geometrically thick with ΔR/R = 0.8-0.9 (more of a wind than a shell) and a low filling factor of order a few percent. The line shapes were consistent with a cylindrical jet, bipolar, or spherical Hubble flow expansion with a maximum speed of about -3000 km s-1. The central peak appeared to be more associated with the spherical component, while the two peaks (especially in Hβ) suggested a ring with either a lower velocity component or with its axis inclined to the line of sight.

We describe a family-based sample of individuals with reading disability collected as part of a quantitative trait loci (QTL) mapping study. Eighty-nine nuclear families (135 independent sib-pairs) were identified through a single proband using a traditional discrepancy score of predicted/actual reading ability and a known family history. Eight correlated psychometric measures were administered to each sibling, including single word reading, spelling, similarities, matrices, spoonerisms, nonword and irregular word reading, and a pseudohomophone test. Summary statistics for each measure showed a reduced mean for the probands compared to the co-sibs, which in turn was lower than that of the population. This partial co-sib regression back to the mean indicates that the measures are influenced by familial factors and therefore, may be suitable for a mapping study. The variance of each of the measures remained largely unaffected, which is reassuring for the application of a QTL approach. Multivariate genetic analysis carried out to explore the relationship between the measures identified a common factor between the reading measures that accounted for 54% of the variance. Finally the familiality estimates (range 0.32-0.73) obtained for the reading measures including the common factor (0.68) supported their heritability. These findings demonstrate the viability of this sample for QTL mapping, and will assist in the interpretation of any subsequent linkage findings in an ongoing genome scan.

Quality of life is important in patients with oral and oropharyngeal cancer. The assessment of quality of life is complex and it is difficult to identify the studies and questionnaires previously reported that have dealt with quality of life assessment in patients with oral cancer. This article gives guidelines for choosing a questionnaire, provides a tabulated summary of 65 studies published in the English language from 1980 to 1997, and gives a brief description of 27 commonly used questionnaires. The review is of particular assistance to the clinician who is considering embarking upon quality of life research in oral cancer.

Intracellular Ca2+ is an important second messenger. In the placenta, regulation of intracellular Ca2+ concentration ([Ca2+]i) by extracellular factors has received relatively little attention. Cultured human placental trophoblasts were treated with a series of potential Ca(2+)-mobilizing ligands. After 3 days in culture, there was an increase in [Ca2+]i in response to angiotensin, endothelin, transforming growth factor-alpha, and ATP in approximately 8, 54, 17, and 100% of the cells, respectively. The response to ATP was dose dependent. At low ATP concentrations (1-10 microM), the response to repeat ATP application remained unchanged, whereas at 100 microM, response to repeat stimulation resulted in lower peak value. The order of potency for the ATP derivatives was ATP = UTP > benzoylbenzoic-ATP > ATP gamma S > ADP beta S > ADP > alpha,beta-MeATP > AMP. This suggests action via the P2u purinergic receptor. Removal of extracellular Ca2+ decreased the ATP-induced Ca2+ response by 45%; this indicates that a substantial portion of the increase in [Ca2+]i was due to influx from extracellular space. Finally, ATP rapidly induced inositol 1,4,5-trisphosphate formation in cultured trophoblasts. Therefore, ATP-induced changes in Ca2+ flux may be due in part to activation of phosphoinositide-specific phospholipase C. In summary, ATP is a potent calciotropic ligand in human placental trophoblasts, acting through the P2u receptor. The effect of ATP on [Ca2+]i may prove to be involved in the modulation of various trophoblast functions, including hormone secretion and active transport of nutrients.

After the diagnosis of cancer, about a third of patients have adjustment disorders. Of recently diagnosed patients, 5 to 15% experience serious psychological disturbances, but their distress is often undetected and untreated. Little attention has been directed to the patients' sources of support and their adequacy.This study assessed a defined group (n = 49) of cancer patients' ratings of the support they received from general practitioners, hospital teams, family, and friends. Additional information was collected on the patients' interest in receiving further hospital services and their psychological morbidity (i.e., anxiety and depression).The results show wide variation in patients' perceptions of the helpfulness of the primary and secondary care teams, raising concern about the levels of help and support available to some cancer patients.Although this sample rated the help received from the hospital very highly, those patients who requested more information from the hospital sector showed little evidence of having had their general anxiety "buffered" by involvement of family members.

Bile salt uptake by hepatocytes is modulated in part by changes in intracellular cyclic AMP. We studied the effect of activation of protein kinase C on cyclic AMP-mediated taurocholate uptake in isolated rat hepatocytes. Both dibutyryl cyclic AMP (2 x 10(-6) mol/L) and glucagon (10(-6) mol/L), which increase intracellular cyclic AMP, enhanced the initial uptake rate of taurocholate into hepatocytes, with maximal increases of 45% to 50% over the basal uptake rate. Vasopressin (10(-9) mol/L), a hormone known to activate protein kinase C, and phorbol-12,13-dibutyrate (10(-5) mol/L) significantly inhibited the glucagon-stimulated increase in taurocholate uptake rate (72% +/- 10% and 105% +/- 13% inhibition, respectively). Basal (unstimulated) taurocholate uptake rate was not affected by vasopressin or phorbol-12,13-dibutyrate. Down-regulation of the glucagon-stimulated transport was rapid and persisted during the 20-min experimental period. Angiotensin II had a similar but more transient inhibitory effect. Vasopressin and phorbol-12,13-dibutyrate suppression of glucagon-stimulated taurocholate uptake rate was not accompanied by diminished cyclic AMP levels. Moreover, vasopressin and phorbol-12,13-dibutyrate inhibited dibutyryl cyclic AMP-stimulated taurocholate uptake rate can be dissociated from alterations in the cyclic AMP levels.

Dual-cure composite resin luting cements are increasingly being used for the cementation of porcelain veneers, composite and ceramic inlays, onlays and crowns. This investigation assessed the effect of a dual-cure adhesive (Bondlite) on the working time of a dual-cure composite resin luting cement (Porcelite Dual-Cure). An oscillating rheometer was used to measure the working time of the composite resin luting cement with and without prior application of dual-cure adhesive. The results demonstrated that use of the dual-cure adhesive significantly reduced the working time of the manufacturer's dual-cure composite resin luting cement.

The goal of this study was to evaluate a correspondence weight control program, and to assess the impact of three program elements (weekly homework, interim weigh-ins, and participation deposits) individually and in combination. All treated participants received 15 weekly standard lessons by mail. Three program features were varied factorially: a) homework assignments, b) interim weigh-ins and c) a deposit refunded contingent on returning homework and/or attending interim weigh-ins. Participants were assigned randomly to active treatment conditions or a delayed treatment control group. Among treated males (N = 14), initial average weight loss and BMI reduction were 9.6 kg and 3.1 respectively; average net weight loss and BMI reduction at one year follow-up were 5.8 kg and 1.9 respectively. Among treated females (N = 128), initial average weight loss and BMI reduction were 3.1 kg and 1.2 respectively; average net weight loss and BMI reduction at one year were 2.3 kg and .88 respectively. Women in all treated groups, except lessons only, showed a greater BMI reduction than untreated controls at the end of treatment. Women in conditions including both homework and interim weigh-ins had greater initial BMI reductions (M = 1.6) than those who received lessons only (M = .76). At one year, net BMI reductions were comparable across all treated groups. Of the 42 women initially registered in conditions that included both homework and weigh-ins, 12 who denied joining other programs lost at least 4.5 kg (M = 7.1) during treatment, and 7 had a net loss of at least 4.5 kg (M = 8.0) at one year without apparent involvement in any other program.

Fifty patients attending for surgical treatment of chronic constipation (n = 21) or faecal incontinence (n = 29) were studied using two psychiatric screening tests: the Hospital Anxiety and Depression (HAD) scale and the General Health Questionnaire (GHQ). Each patient was assessed preoperatively and 6–12 months postoperatively. Results were compared with age and sex-matched controls (n = 50). Constipated patients had significantly higher HAD depression scores compared with controls (median and range): 6 (2–12) versus 4 (0–8), P < 0·05. Constipated patients who were improved by operation (n = 13) had significantly lower preoperative HAD anxiety scores compared with those who were not improved (n = 8): 8 (3–14) versus 15 (10–19), P < 0·01; they also had significantly lower HAD depression scores: 4 (2–12) versus 7 (5–11), P < 0·05. Using these parameters incontinent patients did not differ from controls, but patients who had a bad result after operation (n = 15) had significantly higher HAD anxiety scores than those who obtained clinical benefit (n = 14): 10 (2–15) versus 6 (2–12), P < 0·05; HAD depression scores were also greater: 5 (2–15) versus 3 (0–9), P < 0·05; and GHQ scores were greater: 12 (0–47) versus 4 (0–41), P < 0·05.

The clinical and pathological features of perianal disease in children and adolescents with Crohn's disease have been delineated. Of the 149 patients (mean age 12.1 yr, range 0.75-21 yr, 68% male), 73 (49%) had perianal disease including 51 with fissures and tags, 10 with fistulas, and 12 with abscesses. Ileocolitis was seen in 68% of all patients and in 75% of patients with perianal disease (p greater than 0.10). Rectal inflammation was present in 94% of patients with fistulas or abscesses, or both, versus 63% of all patients without perianal disease (p less than 0.025). Anorectal granulomata were found in 47% of fistula/abscess patients versus 9% of non-perianal disease patients (p less than 0.05). A variety of medical regimens failed to consistently affect these lesions favorably. Four of 10 patients with fistulas healed after 1-5 yr of intermittent discharge. Nine of 12 patients with abscesses required surgical drainage, and 50% subsequently developed chronic fistulas. Granulomata were equally distributed between those patients who healed and those who developed chronic fistulas. Although an important cause of morbidity in childhood Crohn's disease, perianal disease is not progressively destructive in the majority of patients.