cssi/SciSciGPT-SciSciNet huggingface dataset:
Bilayer Thickness Modulates the Conductance of the BK Channel in Model Membranes

The conductance of the BK channel was evaluated in reconstituted bilayers made of POPE/POPS (3.3:1), or POPE/POPS with an added 20% of either SPM (3.3:1:1), CER (3.3:1:1), or CHL (3.3:1:1). The presence of SPM, which is known to increase bilayer thickness, significantly reduced the conductance of the BK channel. To directly test the role of membrane thickness, the conductance of the BK channel was measured in bilayers formed from PCs with acyl chains of increasing length (C14:1–C24:1), all in the absence of SPM. Slope conductance was maximal at a chain length of (C18:1) and much reduced for both thinner (C14:1) and thicker (C24:1) bilayers, indicating that membrane thickness alone can modify slope conductance. Further, in a simplified binary mixture of DOPE/SPM that forms a confined, phase-separated bilayer, the measured conductance of BK channels shows a clear bimodal distribution. In contrast, the addition of CER, which has an acyl chain structure similar to SPM but without its bulky polar head group to POPE/POPS, was without effect, as was the addition of CHL. The surface structure of membranes made from these same lipid mixtures was examined with AFM. Incorporation of both SPM and CER resulted in the formation of microdomains in POPE/POPS monolayers, but only SPM promoted a substantial increase in the amount of the high phase observed for the corresponding bilayers. The addition of CHL to POPE/POPS eliminated the phase separation observed in the POPE/POPS bilayer. The decrease in channel conductance observed with the incorporation of SPM into POPE/POPS membranes was, therefore, attributed to larger SPM-rich domains that appear thicker than the neighboring bilayer.
Flat-panel-detector-based cone-beam CT imaging: preliminary system evaluation

The purpose of this study was to perform a preliminary evaluation of a newly constructed s flat panel detector (FPD)-based system for cone beam CT imaging applications. A prototype flat-panel detector-based cone beam CT imaging system has been designed and constructed by modifying a GE HiSpeed Advantage CT scanner. The prototype consisted of a modified GE CT HiSpeed Advantage CT gantry, an x-ray tube, an 19.5 x 24.4 cm Varian Paxscan 2520 real time flat-panel detector mounted on the gantry, a CT table and an on-gantry PC to control image acquisition. Another PC workstation serving as an operating console controlled the CT gantry and CT table, and sent trigger pulses to dedicated electronic interface modules to control radiographic exposure and to initiate data acquisition. Captured image data sets were first stored in an on-gantry computer and then downloaded from the on-gantry PC to the operating console for high-speed 3D image reconstruction. During data acquisition, the x-ray tube and the FPD can be rotated on the gantry over Nx360 degrees due to integrated slip ring technology. With a single scan, this device was able to acquire up to 288 two-dimensional projections (960 x 768 x 16 bits) for direct 3D reconstruction within 9.6 seconds. This system was used for a series of preliminary phantom studies. Using the continuous scan mode of the scanner, 288 projections were acquired for all volume scans. Direct 3D reconstructions were obtained to evaluate the system for cone beam CT for lung imaging applications. The preliminary results indicate that the newly built flat panel detector-based cone beam CT scanner worked as expected.
Topological electron density analysis of halogen-substituted phosphirenes

Abstract The geometry of 1H-phosphirene (1a) and 2H-phosphirene (2a) and their fluoro-(1b and 2b) and chloro substituted (1c and 2c) analogues were optimized at the HF/6-31G∗ level. Unlike the parent system, the halogenated analogue of 1H-phosphirene is more stable than its isomer: 1b is 21.94 kcal mol−1 below 2b and 1c is 10.51 kcal mol−1 below 2c. The transition states for the reaction 1 → 2 were obtained; the barrier is 87.15 for the parent, 61.01 for the fluorinated system, and 44.24 kcal mol−1 for the chlorinated system. The relative stabilities of the isomers are explained in terms of the strong σ-acceptor properties of the halogens and the electron density distribution. Topological electron density analysis of points along the reaction coordinate for the conversion of 1a into 2a reveal some novel bond path networks.
PET/MRI: Methodology and Clinical Applications

I. Carrio and P. Ros, Eds. New York, NY: Springer, 2014, 163 pages, $179 Following the success of PET/CT in clinical applications, it would seem logical that PET/MR imaging can provide an innovative alternative taking full advantage of the superiority of MR imaging over CT in differentiating soft
Graphic analysis of isobiological effectiveness for twice‐a‐day radiotherapy regimens and its application

The effectiveness of twice-a-day (BID) hyperfractionated radiotherapy (RT) schedules has been demonstrated for carcinomas of the head and neck, the lung, and advanced stage breast cancers. Fractionation choices include identical or different doses of the two daily treatments referred to as equally split or unequally split BID doses, respectively. The choices of equally split, unequally split, or a mixture of both are based on the consideration of maximal tumor control or minimal late tissue effect. The comparison of biological effectiveness of different regimens is commonly done by computing the individual biological effective doses (BED) to tumor and late tissue. For this purpose, a different theoretical approach which adopts the concept of isobiological effectiveness may be more general and analytic than point dose computation. Taking advantage of the quadratic nature, a graphic analysis of isobiological effectiveness (GAIBE) was developed to analyze how to optimize the regimens for tumor killing effect and late tissue sparing effect. In this analysis, a Cartesian plot of two dose axes representing the two daily doses is used. The loci of isobiological effective dose (isoBED) regimens are circular on this plot. Thus, the effects of many regimens on tumor and late reacting tissue may be observed simultaneously by comparing the isoBED loci. Graphically, with GAIBE analysis and, mathematically, for a given isoBED to tumor, we have demonstrated that equally split hyperfractionation schedules will deliver the lowest biological effectiveness to late reacting tissues among all isoBED regimens to tumor. Situations when unequally split regimens are beneficial are also discussed. Another variable of clinical importance is the repopulation phenomenon which may counteract the biological effectiveness with increasing length of treatment course. The additive nature of BED from daily treatments allows GAIBE analysis to compensate for the repopulation phenomenon and aid the determination of the course length. Our analysis can also be used for the design of concomitant boost BID regimens. A subroutine in BASIC language has been developed and is available upon request. As a corollary of GAIBE analysis, for a chosen total dose, once-daily treatment (QD) will result in the most tumor killing and the BID half-dose exposures will have the least tumor killing. Other combinations of BID exposures with the sum of doses equal to QD exposure will have varying degrees of tumor killing which fall in between these two extremes. This concept from GAIBE analysis may be applied to determine α/β values for tumor cell lines using equally split exposures. © 1994 Wiley-Liss, Inc.
FDG for Therapy of Metabolically Active Tumors

(18)F-2-deoxy-2-fluoro-D-glucose ((18)F-FDG, later referred to as (19)FDG) has been extensively used in diagnostic positron emission tomography (PET) in oncology for many years. FDG is a glucose analog that is taken by cells in a similar fashion as glucose and is phosphorylated by hexokinase to (18)F-FDG-6-phosphate but cannot undergo further glycolysis, and hence is trapped in the cell. Metastatic cancer remains a major cause of death men and women, surpassed only by heart disease. Despite the enormous research efforts resulting in emergence of novel drug candidates, there is little progress in improving the survival of patients with many types of solid tumors. Thus, novel therapies to combat metastatic cancer are urgently needed. With a physical half-life of almost 2 hours, (18)F emits energetic positrons with high abundance (96%) and a path length in tissue of ∼0.1-0.2 cm. Theoretically, these positrons can kill cancer cells in the same manner as electrons by damaging DNA and cellular machinery and inducing apoptosis/necrosis of the tumor cells. Several years ago, we explored, in a first series of comprehensive studies, the therapeutic potential of FDG in experimental breast cancer and showed its efficacy and safety. Since then, FDG therapy has been shown to be effective and safe in experimental melanoma, colon cancer, as well as in eliminating in vitro the endothelial cells in blood vessels, which supply the tumors with nutrients. The next step forward in translation of FDG therapy into the clinic should be a phase II clinical trial. Also, recent developments in targeted PET imaging could increase the range of PET pharmaceuticals potentially useful for positron therapy of metastatic cancers because of increased specificity of these tracers in comparison with FDG.
D1 Receptor Activation in the Mushroom Bodies Rescues Sleep-Loss-Induced Learning Impairments in Drosophila

Background: Extended wakefulness disrupts acquisition of short-term memories in mammals. However, the underlying molecular mechanisms triggered by extended waking and restored by sleep are unknown. Moreover, the neuronal circuits that depend on sleep for optimal learning remain unidentified. Results: Learning was evaluated with aversive phototaxic suppression. In this task, flies learn to avoid light that is paired with an aversive stimulus (quinine-humidity). We demonstrate extensive homology in sleep-deprivation-induced learning impairment between flies and humans. Both 6 hr and 12 hr of sleep deprivation are sufficient to impair learning in Canton-S (Cs) flies. Moreover, learning is impaired at the end of the normal waking day in direct correlation with time spent awake. Mechanistic studies indicate that this task requires intact mushroom bodies (MBs) and requires the dopamine D1-like receptor (dDA1). Importantly, sleep-deprivation-induced learning impairments could be rescued by targeted gene expression of the dDA1 receptor to the MBs. Conclusions: These data provide direct evidence that extended wakefulness disrupts learning in Drosophila. These results demonstrate that it is possible to prevent the effects of sleep deprivation by targeting a single neuronal structure and identify cellular and molecular targets adversely affected by extended waking in a genetically tractable model organism.
Rapid monitoring of site-specific glycosylation microheterogeneity of recombinant human interferon-γ

An analytical system is presented for rapid assessment of site-specific microheterogeneity of the two potential N-linked glycosylation sites of recombinant human interferon-γ (IFN-γ) derived from Chinese hamster ovary cell culture. The target protein is first purified from culture supernatant by immunoaffinity chromatography, and the acidic eluent is neutralized via an in-line mixing tee. On-line proteolysis is rapidly performed by an immobilized trypsin cartridge, and reversed-phase chromatography isolates the two pools of glycopeptides representing the potential glycosylation sites. Following off-line analysis by matrix-assisted laser-desorption ionization/time-of-flight (MALDI/TOF) mass spectrometry, observed mass shifts of glycopeptides relative to the known masses of their amino acid portions are correlated to site-specific oligosaccharide structures. Desialylation of glycopeptides by sialidase treatment on the MALDI sample plate allows for quantitative estimations of asialoglycan structures by MALDI...
Increasing Melanoma Screening Among Hispanic/Latino Americans A Community-Based Educational Intervention

Melanoma incidence is increasing among Hispanics/Latinos in California. This community-based project reached out to a rural Hispanic/Latino community in North San Diego County to provide melanoma prevention and screening education. At a local community health fair, bilingual volunteer lay health workers led 10- to 15-minute-long information sessions on melanoma disease, risk factors, and skin self-examination techniques. Pearson chi-square analyses of participants’ (N = 34) responses to pre- and postintervention evaluation surveys indicate significant increases in knowledge, risk awareness, and self-efficacy for self-screening. The results revealed that Hispanics/Latinos in a low socioeconomic stratum might be at moderate to high risk for developing melanoma. Their low annual income, low level of education, occupational sun-exposure, and lack of access to health care are likely factors that deter at-risk Hispanics/Latinos from seeking health care.
Whitman and Kate Field

Documents American feminist journalist, lecturer, and actor Kate Field's (1838-1896) admiration for Whitman.
On the cell cycle and its switches

For the cell-division cycle to progress, hundreds of genes and proteins must be coordinately regulated. Systems-level studies of this cycle show that positive-feedback loops help to keep events in sync.
Radioiodinated MIBG in paraganglioma and pheochromocytoma: previous results and early experiences using no-carrier-added MIBG

Abstract The majority of pheochromocytomas and paragangliomas are benign, with malignancy occurring in approximately 10% of pheochromocytoma patients. The malignancy rate among paragangliomas is 15–35% or higher if associated with succinate dehydrogenase B gene mutations. The 5-year mortality rate in malignant pheochromocytoma and paraganglioma is nearly 50%. Malignancy of both pheochromocytoma and paraganglioma is determined by the existence of metastasis or local invasion and not by the cellular characteristics. There are no known clinical, biochemical or histopathological differences between pheochromocytoma and paraganglioma. Metaiodobenzylguanidine (MIBG) radiolabeled with either 123 I or 131 I has been used to diagnose neuroendocrine tumors such as paraganglioma and pheochromocytoma, and 131 I-MIBG has been used to treat these tumors. The role of radioiodinated MIBG in treating neuroendocrine tumors is still being evaluated. More recently, no-carrier-added (nca) MIBG has become available, and the advantages of nca MIBG over ca MIBG are being demonstrated. This article reviews the biology of paragangliomas and pheochromocytomas, the role of MIBG imaging in the diagnosis of these tumors and the role of both ca and nca 131 I-MIBG in the treatment of these tumors. New data on nca 131 I-MIBG in the therapy of these tumors are included.
The nature of the dominant deep trap in amorphous silicon nitride films: Evidence for a negative correlation energy

Abstract A recent study by Krick and coworkers provided the first direct evidence associating a specific point-defect with trapping phenomena in silicon nitride films. Krick and coworkers demonstrated that silicon “dangling bond” centers in silicon nitride films are electrically neutral when paramagnetic and are rendered diamagnetic when they trap an electron or a hole. We show that these centers exhibit behavior consistent with a negative electron-electron correlation energy, a so-called negative U . With a negative U there is a strong attractive interaction between spin-up and spin-down electrons on the same dangling bond site. This attractive interaction implies that, in thermodynamic equilibrium, nearly all of the defect sites will be diamagnetic - either positively or negatively charged.
Ferroan anorthosite: a widespread and distinctive lunar rock type

Eight of eleven Apollo 16 rake-sample anorthosites are very similar to each other, to hand-specimen Apollo 16 anorthosites, and to Apollo 15 anorthosites. They have feldspar An-96.6, both high- and low-Ca pyroxene with a restricted range of (low-magnesium) composition, minor olivine, traces of ilmenite and chromite, and originally coarse-grained, but now cataclastic texture. Such ferroan anorthosite is evidently a coherent, distinctive and widespread lunar rock type of cumulate origin which may not necessarily be very closely related genetically to other highland rock types.
Standing and mortality in a prospective cohort of Canadian adults.

KATZMARZYK, P. T. Standing and Mortality in a Prospective Cohort of Canadian Adults. Med. Sci. Sports Exerc. ,V ol. 46, No. 5, pp. 940–946, 2014. Purpose: Several studies have documented significant associations between sedentary behaviors such as sitting or television viewing and premature mortality. However, the associations between mortality and other low-energy-expenditure activities such as standing have not been explored. The purpose of this study was to examine the association between daily standing time and mortality among 16,586 Canadian adults 18–90 yr of age. Methods: Information on self-reported time spent standing as well as several covariates including smoking, alcohol consumption, physical activity readiness, and moderate-to-vigorous physical activity was collected at baseline in the 1981 Canada Fitness Survey. Participants were followed for an average of 12.0 yr for the ascertainment of mortality status. Results: There were 1785 deaths (743 from cardiovascular disease [CVD], 530 from cancer, and 512 from other causes) in the cohort. After adjusting for age, sex, and additional covariates, time spent standing was negatively related to mortality rates from all causes, CVD, and other causes. Across successively higher categories of daily standing, the multivariable-adjusted hazard ratios were 1.00, 0.79, 0.79, 0.73, and 0.67 for all-cause mortality (P for trend G0.0001); 1.00, 0.82, 0.84, 0.68, and 0.75 for CVD mortality (P for trend 0.02); and 1.00, 0.76, 0.63, 0.67, and 0.65 for other mortality (P for trend G0.001). There was no association between standing and cancer mortality. There was a significant interaction between physical activity and standing (P G 0.05), and the association between standing and mortality was significant only among the physically inactive (G7.5 METIhIwk j1 ). Conclusions :T he
Sub-wave nature of the albino rat electroretinogram.

Abstract ERG's were recorded from dark adapted albino rats using corneal electrodes in response to stimuli varying in intensity and duration, and during the recovery from a mild light adaptation. The amplitudes, latencies, and peak latencies of the a -wave, the multiple peaks in the b -wave, and the negative wave following the b -wave were obtained as a function of these stimuli. The b -wave amplitude increases with stimulus duration when a constant low intensity stimulus is used, but decreases with stimulus duration for high intensity stimuli. The b -wave peak latency remained constant while the b -wave amplitude increased with increasing stimulus intensity, but decreased in the region in which the b -wave amplitude remained constant. Shortly after an adapting light is turned off, a small peak appears on the descending edge of the b -wave. This peak increases in amplitude with increasing dark adaptation until it becomes the most dominant peak in the b -wave. At that time there is a discontinuity in the overall b -wave peak latency vs. recovery time curve to a higher value. The amplitudes and peak latencies of the individual peaks in the b -wave are continuous, however. The results are interpreted in terms of a model that assumes that the b -wave is composed of a number of sub-waves. Each sub-wave can be the result of a different homogeneous population of retinal cells interacting with the light stimulus, or by a series of reactions occurring within the retina, leading to the generation of an electrical potential. Each population of cells would have different thresholds, latencies and sensitivities. The summation of the reactions of all the different populations of cells to the same stimulus results in the b -wave. It is proposed that the lowest threshold (most sensitive) populations of cells produce sub-waves having the longest latencies and that these sub-waves are the first to be affected by light adaptation.
A control technology evaluation of state-of-the-art, perchloroethylene dry-cleaning machines.

NIOSH researchers evaluated the ability of fifth-generation dry-cleaning machines to control occupational exposure to perchloroethylene (PERC). Use of these machines is mandated in some countries; however, less than 1 percent of all U.S. shops have them. A study was conducted at a U.S. dry-cleaning shop where two fifth-generation machines were used. Both machines had a refrigerated condenser as a primary control and a carbon adsorber as a secondary control to recover PERC vapors during the dry cycle. These machines were designed to lower the PERC concentration in the cylinder at the end of the dry cycle to below 290 ppm. A single-beam infrared photometer continuously monitors the PERC concentration in the machine cylinder, and a door interlock prevents opening until the concentration is below 290 ppm. Personal breathing zone air samples were measured for the machine operator and presser. The operator had time-weighted average (TWA) PERC exposures that were less than 2 ppm. Highest exposures occurred during loading and unloading the machine and when performing routine machine maintenance. All presser samples were below the limit of detection. Real-time video exposure monitoring showed that the operator had peak exposures near 160 ppm during loading and unloading the machine (below the OSHA maximum of 300 ppm). This exposure (160 ppm) is an order of magnitude lower than exposures with more traditional machines that are widely used in the United States. The evaluated machines were very effective at reducing TWA PERC exposures as well as peak exposures that occur during machine loading and unloading. State-of-the-art dry-cleaning machines equipped with refrigerated condensers, carbon adsorbers, drum monitors, and door interlocks can provide substantially better protection than more traditional machines that are widely used in the United States.
Optimal Power Generation Unit Sizing for Combined Heating and Power Systems With Uncertain Loads and Fuel/Electricity Prices

An optimal sizing method is developed in this work based on an analytical scheme for determining optimal operation decisions. Using the analytic optimal operation scheme allows for a more thorough optimal sizing method because of the minimal computational effort required as compared to mixed integer programming approaches. For example, an optimal sizing method based on this approach can more feasibly consider several years of weather data and the range of likely fuel/electricity costs for the term of operation of the PGU. The optimal sizing method in this work takes advantage of this efficient optimal operation scheme and provides a robust optimal solution with respect to weather and fuel/electricity cost uncertainty. A case study of a medium sized office building is carried out by testing the algorithm for a range of 20 commercially available diesel engine PGUs.Copyright © 2011 by ASME
Differential Effects of WISC-R Factors on Special Education Eligibility for Three Ethnic Groups:

The influence of the WISC-R factors, identified by Kaufman (1975), on special education eligibility was examined for three ethnic groups. A multiple regression procedure was used to analyze data on...
Der geschwindigkeitsbestimmende Schritt bei der Decarboxy-lierung von 2,4-Dihydroxybenzoesäure in mässig konzentrierter wässeriger Salzsäure†

The decarboxylation kinetics of 2,4-dihydroxybenzoic acid have been studied in 0.1–8 N aqueous HCl at 50°. At low HCl concentrations, the observed first order rate constant, k, increases with increasing acidity of the solution. In solutions with 3.5–6 N HCl, k remains constant. The D2O solvent isotope effect decreases from kH2O/kD2O = 2.0 in 1N HCl to 1.3 in 5 N HCl, and it remains unchanged at 1.3 if the HCl concentration is increased further to 8 N. It is concluded that an increase of the acidity of the solution causes a change of the rate determining step from slow proton transfer to rate limiting CC bond cleavage.
Abstract B92: Satisfaction with a breast cancer patient navigation program: Perspectives of patients, navigators, and clinical staff

Introduction: Patient navigation interventions are an emerging approach to reducing cancer disparities but few formal evaluations have been published. The purpose of this study was to evaluate perceptions of a breast cancer patient navigation program among patients, patient navigators (PNs), and breast cancer clinic staff members. Methods: Post-program interviews were conducted with 218 navigated patients. Individual semi-structured interviews were conducted with 5 PNs. Surveys were administered to 19 clinic staff. Results: Perceptions among Navigated Patients (n=218). Fifty-three percent of the surveyed patients were African American (n=116), 15.1% were Hispanic (n=33), 33.9% were married (n=74), 65.1% had ≤ a high school degree (n=142), and 75.2% had an annual income Perceptions among Navigators (n=5). Strengths of the program cited by the five navigators included: (a) the satisfaction that stems from helping patients receive needed health services; (b) recognition of the role of religious beliefs in the treatment decision-making of patients; (c) the need for navigators to be organized so they can effectively coordinate treatment among different clinicians for the patient; (d) using creative solutions to maintaining contact with navigated patients, such as pre-paid cell phones; and (e) meeting the challenges involved in working with patients with a wide variety of needs. Weaknesses of the program cited by the five navigators included: (a) difficulty in clarifying/distinguishing the roles of navigators and social workers; (b) language barriers with non-English speaking patients and the need to rely on hospital translation services, which often resulted in delayed provision of navigation services and slowed the clinic visit; and (c) the difficulty of presenting complex medical information in lay language to patients. Perceptions among Breast Cancer Clinic Staff Members (n=19). All respondents agreed/strongly agreed that navigators were knowledgeable, available when needed, and related well with navigated patients, breast clinicians and staff. Respondents agreed/strongly agreed that compared to patients who did not have a patient navigator, navigated patients were more prepared with requested documents needed for the clinic appointment (73.7%), missed fewer clinic appointments (76.5%), were more informed about their breast cancer treatment (89.5%), and received more timely breast cancer treatment (68.4%). Conclusions: We adopted a “triangulation” strategy to integrate perceptions of a patient navigation program through the eyes of patients, navigators, and breast cancer clinic staff members. The results show that the patient navigation program was favorably reviewed by these constituencies. Citation Information: Cancer Epidemiol Biomarkers Prev 2010;19(10 Suppl):B92.
Point of care ultrasound (POCUS) telemedicine project in rural Nicaragua and its impact on patient management

Point of care ultrasound (POCUS) is a useful diagnostic tool in medicine. POCUS provides an easy and reproducible method of diagnosis where conventional radiologic studies are unavailable. Telemedicine is also a great means of communication between educators and students throughout the world. Implementing POCUS with didactics and hands-on training, using portable ultrasound devices followed by telecommunication training, will impact the differential diagnosis and patient management in a rural community outside the United States. This is an observational prospective study implementing POCUS in Las Salinas, a small village in rural western Nicaragua. Ultrasound was used to confirm a diagnosis based on clinical exam, or uncover a new, previously unknown diagnosis. The primary endpoint was a change in patient management. International sonographic instructors conducted didactic and practical training of local practitioners in POCUS, subsequently followed by remote guidance and telecommunication for 3 months. A total of 132 patients underwent ultrasound examination. The most common presentation was for a prenatal exam (23.5 %), followed by abdominal pain (17 %). Of the 132 patients, 69 (52 %) were found to have a new diagnosis. Excluding pregnancy, 67 patients of 101 (66 %) were found to have a new diagnosis. A change in management occurred in a total of 64 (48 %) patients, and 62 (61 %) after excluding pregnancy. Implementing POCUS in rural Nicaragua led to a change in management in about half of the patients examined. With the appropriate training of clinicians, POCUS combined with telemedicine can positively impact patient care.
Chemical signals of epiphytic lichens in southwestern North America; natural versus man-made sources for airborne particulates

Ambient airborne particulate matter (PM) in southwestern North America consists of naturally derived desert dust, plus anthropogenic inputs from several sources. Epiphytic lichens (Usnea sp.) in this region are a useful biomonitor for the airborne PM because they derive nutrients and moisture largely from incorporated atmospheric aerosols, and not by absorption from the host tree limb from which they are suspended. Using a broad-based sampling strategy from southern Chihuahua, Mexico, to northern New Mexico, USA, we show that select elemental abundance ratios and lead isotopes from epiphytic lichens are useful for distinguishing between sources of airborne PM, and for gauging anthropogenic inputs into desert ecosystems. Abundance patterns of the trace elements La, Nd, and Sm in the lichens suggest origination from continental crust, but rare earth elements display a pronounced enrichment relative to the major element Fe by a factor of about 5. This enrichment appears related to geologic weathering, aeolian transport, and grain-size biases toward trace-element-rich mineral grains in the arid setting. Using the metal Pb as an indicator of human inputs, epiphytic lichens typically show Pb enrichments by a factor of about 25–60 over typical upper crustal values. Regional-scale differences in Pb isotope ratios of these lichens relate to different pollutant sources in southwestern North America.
Central regulation of ejaculation

Ejaculation is a reflex mediated by a spinal control center, referred to as a spinal ejaculation generator. This spinal ejaculation generator coordinates sympathetic, parasympathetic and motor outflow to induce the two phases of ejaculation, i.e., emission and expulsion. In addition, the spinal ejaculation generator integrates this outflow with inputs that are related to the summation of sexual activity prior to ejaculation that are required to trigger ejaculation. Recently, a group of spinothalamic neurons in the lumbar spinal cord (LSt cells) were demonstrated to comprise an integral part of the spinal ejaculation generator. Specifically, lesions of LSt cells completely ablate ejaculatory function. Moreover, LSt cells are activated following ejaculation, but not following other components of sexual behavior. Furthermore, based on their relationship with autonomic nuclei, motoneurons and genital sensory inputs, LSt cells are also in the ideal anatomical position to integrate sensory inputs and autonomic and motor outflow. Additionally, the spinal ejaculation generator is under inhibitory and excitatory influence of supraspinal sites, including the nucleus paragigantocellularis (nPGi), the paraventricular nucleus of the hypothalamus (PVN) and the medial preoptic area (MPOA). Finally, sensory information related to ejaculation is processed in the spinal cord and brain, possibly contributing to the rewarding properties of ejaculation. One candidate pathway for relay of ejaculation-related cues consists of LSt cells and their projections to the parvocellular subparafascicular thalamic nucleus. Moreover, neural activation specifically related to ejaculation is observed in the brain and may reflect of processing of ejaculation-related sensory cues.
Monitoring the effects of Dracunculiasis remediation on agricultural productivity using satellite data

Abstract Dracunculiasis has been shown to be a major cause of agricultural work loss in many parts of West Africa. Monitoring the magnitude of agricultural loss caused by this parasite has been a problem due to the non-market nature of the agricultural output, which is often used for subsistence or barter. To test the hypothesis that ‘ Optimization of water and sanitation interventions in areas with high Dracunculiasis prevalence have a measurable socio-economic impact’ a temporal analysis of Landsat Thematic Mapper (TM) satellite data was conducted. A region in which intervention had not taken place (the control) and a region in which it had were compared to determine the change in agricultural activity. Paired comparisons were made of the difference between two Landsat TM data sets, a 31 January 1986 scene ( pre-intervention) and a 5 January 1991 scene (post-intervention) using the digital number ( DN) values in bands 5, and 7, and the Normalized Difference Vegetation Index (NDVI) calculated from bands ...
Dynamic monitoring of financial intermediaries with subordinated debt

Purpose – The purpose of this paper is to show that subordinated debt regulatory proposals assume that transactions in the secondary market of subordinated debt can attenuate moral hazard on the part of management if secondary market prices are informative signals of the risk of the institution. Owing to the proprietary nature of dealer prices and the liquidity of secondary transactions, the practical value of information provided by subordinated debt issues in isolation is questionable.Design/methodology/approach – A multivariate dynamic risk signal is proposed that combines fluctuations in equity prices, subordinated debt and senior debt yields. The signal is constructed as a coincident indicator that is based in a time series model of yield fluctuations and equity returns. The extracted signal monitors idiosyncratic risk of the intermediary because yields and equity returns are filtered from market conditions. It is also predictable because it is possible to construct a leading indicator based almost e...
Band offsets in c-Si/Si-XII heterojunctions

Abstract Silicon has a rich phase diagram with a multitude of phases existing over a wide range of pressures and temperatures, in addition to the common cubic silicon (c-Si) phase. One such phase, Si-XII, was first observed less than 2 decades ago in diamond anvil experiments, and more recently as a product of nanoindentation. In some of these latter experiments, I–V measurements were performed to characterize the c-Si/Si-XII interface that results when Si-XII is formed in cubic silicon substrates. In this paper we describe calculations of the band offsets in c-Si/Si-XII heterojunctions. We find that the heterojunction is of Type I and that the band offsets are estimated to be Δ E v = 0.3 eV and Δ E c = 0.5 eV for the valence bands and conduction bands, respectively.
Universal traversal sequences for paths and cycles

Abstract One approach to the reachability problem for rooted undirected graphs G is to order the neighbors of each vertex and traverse all vertices of the connected component containing the root by means of a sequence of positive integers (si)i ≥ 1 interpreted as instructions of the form, “Move to the sith neighbor or of the current vertex.” A sequence that does this for all d-regular connected graphs with n vertices is called an (n, d)-universal traversal sequence. Although the existence of universal traversal sequences is easy to verify, known methods for their construction involve some sort of exhaustive search. In this paper, a recursive algorithm for the construction of (n, 2)-universal traversal sequences in space O(log2n) is described.
Variation for X chromosome expression in mice detected by electrophoresis of phosphoglycerate kinase

The proportions of the two isozyme bands of the X-linked form of phosphoglycerate kinase (PGK-1) were compared in 16 tissues from four groups of adult heterozygous females. Little evidence was found for differences in expression of the two isozymes among tissues but there was a marked difference among the four groups of mice. The proportion of the PGK-1B enzyme was consistently lower in PGK-1AB heterozygous daughters of C3H/HeHa females than in corresponding heterozygotes with a C57BL/6Ha, DBA/2Ha or JBT/Jd mother. This difference was also observed in foetuses on the fourteenth day of gestation irrespective of whether the C3H/HeHa X chromosome was derived from the mother or the father. Sequential sampling of blood from the same heterozygous females provided no evidence for genetically determined cell selection in the adult erythropoietic tissue. The observed differences probably reflect variation at an X-chromosome controlling element locus among inbred strains of mice, similar to that described by Cattanach & Williams (1972) using X-linked morphological markers, although this has yet to be tested.
Theoretical analysis of hot electron collection in metal-insulator-metal devices

We propose a new architecture of metal-insulator-metal devices for solar energy harvesting at infrared and visible frequencies based on asymmetrical alignment of insulating barrier relative to the Fermi level of metals and spatial localization of hot electrons excited by photons. Photons absorbed by metals create hot electrons, which can transmit through the thin insulating barrier, producing current. We theoretically investigated the photocurrent response and power generations at different wavelengths. Short circuit current and open circuit voltage can be easily tuned by changing metal thicknesses to adjust the forward and reverse photocurrent. By employing surface plasmons, power generation efficiency is enhanced 9 times in a grating MIM device compared to direct illumination at 650 nm. Finally, we compared the enhancement of power generation efficiency by SPs excited through grating structure and Kretschmann coupling system.
“Take Five” Blends Classroom and Cafeteria to Promote Fruit and Vegetable Consumption

Abstract LEARNING OUTCOME: To determine the effectiveness of utilizing the cafeteria as well as the classroom to provide nutrition education. The 5 A Day for Better Health Program is a national effort to increase Americans' fruit and vegetable consumption to five servings daily - one of the objectives of Healthy People 2000. Previous research has shown that only 23% of Americans currently consume the recommended number of servings. In Nevada, a 5 A Day program was implemented in two public schools with culturally diverse students from low socio-economic backgrounds. These groups have been found to consume fewer fruits and vegetables than other groups. The objectives of the program were to increase knowledge, improve attitudes, and promote the consumption of fruits and vegetables. The program, entitled "Take Five" was unique in that educational classroom activities were complemented by activities in the school cafeteria. Once a week for 16 weeks, classroom teachers presented students with "Take Five" nutritional information and preparation tips on the weekly featured fruit and vegetable. This was reinforced at lunch time in the cafeteria where students received fresh fruit and vegetable samples. Students also earned "points" by participating in the program, making them eligible for prizes. The program was evaluated using a pre/post-test design. Results showed that student's attitudes about the acceptability of eating fruits and vegetables improved significantly (p=.005) as did their perception of their ability to eat five fruits and vegetables per day (p
Boredom in Free Time: Relationships with Personality, Affect, and Motivation for Different Gender, Racial and Ethnic Student Groups

The propensity to experience boredom in free time was investigated by exploring relationships with the individual's demographic characteristics, personality, motivational orientation, and affective style assessed through group-administered questionnaires to 999 university students. The self-as-entertainment personality attribute consistently predicted the likelihood that students would be bored, and inverse relationships with extraversion and intrinsic motivational orientation were found for all student groups. Multiple regression analyses revealed that race, ethnicity, and gender were the only significant demographic predictors of the likelihood an individual would be bored in free time. Group similarities and differences in depicting students who were prone to experience boredom in free time are described.
The layer concept: utilization in determining the pain generators, pathology and how structure determines treatment

The level of understanding of pain in the non-arthritic hip has made significant strides in the last couple of decades beginning with the discoveries of Reinhold Ganz, MD. However, even with the detection of subtle bony abnormalities, including femoroacetabular impingement, a clinician’s ability to differentiate pain generators in the hip has been ambiguous. Deciphering the etiology of the pathology versus the pain generator is essential in prescribing the proper treatment. The Layer Concept developed by Dr. Bryan Kelly, is a systematic means of determining which structures about the hip are the source of the pathology, which are the pain generators and how to then best implement treatment. Four layers will be discussed in this article. Layer I, the osseous layer, Layer II, the inert tissue layer, Layer III, the contractile layer and Layer IV, the neuromechanical layer.
Percutaneous endoscopic gastrostomy tube placement in a surgical training program.

Background This study examines the patterns of use of percutaneous endoscopic gastrostomy (PEG) and primary open gastrostomy (Gtube) performed in a residency training program in surgery. Methods A retrospective cohort study that assesses the indications and outcomes of 317 PEGs and 75 isolated Gtubes used for gastric access between 1987 and 1997. Results The demographics and risk factors of the patients receiving Gtube and PEG were comparable. The mean number of PEGs performed per resident is currently 13 per year (mean 5 over 10 years) with a 97% PEG success rate; an 88% success rate is demonstrated for placement of jejunal extensions. Conclusions PEGs are generally preferable to Gtubes as primary procedures. Surgical residents should become competent in PEG placement by performing adequate numbers of procedures with fully trained staff.
Multivariate integration on hypercubic and mesh networks

Abstract We analyze a class of adaptive algorithms for integration over N-dimensional hyper-rectangular or simplical regions, on distributed systems. An adaptive algorithm attempts to achieve the requested accuracy by refining the subdivision of the integration region, thus allowing for a concentration of subdivisions near singularities. At the subdivision of a region, the error behaves according to a prescribed model, relating the error of the parent region to that of its children. The analysis can also be applied to problems in other areas, as long as the task selection is based on a priority function which behaves according to a suitable model. Using an efficient management of the subregions, we show that an O (p/ log p) speedup can be achieved on a p-processor hypercubic network, such as shuffle exchange, butterfly and hypercube. Furthermore, a speedup of O ( p ) can be achieved on a p × p mesh network. We also show that our algorithms compare favorably with well-known dynamic load balancing strategies.
The politics of cultural pluralism in Ethiopia and Eritrea: trajectories of ethnicity and constitutional experiments

Abstract Theoretical discourse on nationalism and ethnicity has crystallized around three schools of thought: primordialism, instrumentalism and constructivism. I take an instrumentalist approach to examine the processes that shaped the drafting of the new constitutions of Ethiopia and Eritrea, with particular focus on the role of elites in group identity definition, formation and mobilization. I argue that despite their similar ethnic and religious segmentation, levels of economic development, and cultural heritage, the qualitatively different approaches to group accommodation which Ethiopia and Eritrea have pursued are explained by and are functions of (i) each country's constitutive myths — that is, the trajectory of ethnicity traversed over time in altering existing myths and constructing alternative myths; (ii) the leaders’ behaviour of avoiding risk at all cost; and (iii) the political uncertainties that prevailed in both countries at the time the regime of Mengistu Haile Mariam was overthrown. Toge...
Emergence of truly "individualized" therapy: the poly (adenosine diphosphate-ribose) polymerase inhibitors.

Introduction: The process of DNA surveillance for, and repair of, intrinsic and extrinsic injury is complex, redundant, and necessary for cell viability. An enzyme family involved in this oversight is the poly (adenosine diphosphate [ADP]-ribose) polymerases (PARPs), which primarily function to repair single strand injury [1]. PARP enacts this function through a process known as nucleotide base excision and repair. It was recently discovered that the inhibition of PARP promotes the probability for double strand DNA breaks at replication forks. Under normal conditions, these injuries are managed through successful error-free homologous recombination [2]. However, if this function is further thwarted, DNA damage ensues, leading to catastrophic genetic aberrations and mortality. Such is the case in cells that harbor mutations in BRCA1 or BRCA2. These tumor suppressor genes, known for their association with familial breast, ovarian, and prostate cancer, among others, play an active role in homologous recombination under normal conditions. BRCA1 appears to function predominately in the signaling of DNA double strand breaks, whereas BRCA2 appears mechanistically important to the homologous repair process itself [3]. Nevertheless, when tumors develop in patients who are heterozygous for a mutant allele, the otherwise compensating normal BRCA allele becomes compromised or inactivated, enabling cumulative DNA injury. The apparent signifi cant role of PARP in DNA repair under these circumstances led to the hypothesis that PARP inhibition in cells lacking BRCA-directed homologous recombination would be lethal. Further, because PARP inhibition in cells heterozygous for BRCA is no more toxic than in cells with normal BRCA, the hypothetical therapeutic window would appear to be large [4,5].