cssi/SciSciGPT-SciSciNet huggingface dataset:
The effectiveness of diabetes education in rural clinical practice

Objective: Type 2 Diabetes affects approximately 10% of the population in the United States. Diabetes is associated with acute and long-term complications are more severe. Studies are providing a correlation between better self-care actions and a reduction of undesired diabetes outcomes. The purpose of this study was to evaluate the implementation of a diabetes self-management education (DSME) program on glycemic control that was expected to improve staff knowledge and diabetes outcomes. Methods: This study conducted a quality improvement design. Providers and nursing staff in three primary care clinics were recruited. Diabetes Knowledge Test (DKT) and HbA1c were measured pre and post intervention. Results: Data from 15 staff participants were analyzed. The mean score for the pre-test was 81% while the mean score for the post-test was 87%. A paired t -test revealed t = 1.533, df = 3.998 and p = .160. The HbA1c percentage mean over 6 months decreased by 0.02% and subsequently in 3 months by 0.17%. The Friedman rank sum test was used to compare the differences, χ 2 (2) = 14.79, p < .001. Post-hoc analysis identified a statistical significance in the HbA1c from implementation to post implementation. Conclusions: There was an increase in the percent score in the provider and nursing staff knowledge after implementation of the DSME program. A decrease in percent change of the HbA1c was identified over the three- month implementation period. This study demonstrated that the implementation of a DSME program may contribute to improved glycemic control.
Uncovering Unappreciated Activities and Niche Functions of Bacterial Cell Wall Enzymes

A peptidoglycan (PG) cell wall is an essential component of nearly all bacteria, providing protection against turgor pressure. Metabolism of this PG meshwork must be spatially and temporally regulated in order to support cell growth and division. Despite being an active area of research for decades, we have only recently identified the primary PG synthesis complexes that function during cell elongation (RodA-PBP2) and cell division (FtsW-FtsI), and we are still uncovering the importance of the other seemingly redundant cell wall enzymes. In this minireview, we highlight the discovery of the monofunctional glycosyltransferases RodA and FtsW and describe how these findings have prompted a re-evaluation of the auxiliary role of the bifunctional class A penicillin-binding proteins (aPBPs) as well as the L,D-transpeptidases (LDTs). Specifically, recent work indicates that the aPBPs and LDTs function independently of the primary morphogenetic complexes to support growth, provide protection from stresses, mediate morphogenesis, and/or allow adaptation to different growth conditions. These paradigm-shifting studies have reframed our understanding of bacterial cell wall metabolism, which will only become more refined as emerging technology allows us to tackle the remaining questions surrounding PG biosynthesis.
MDPV “high-responder” rats also self-administer more oxycodone than their “low-responder” counterparts under a fixed ratio schedule of reinforcement

Oxycodone is one of the most commonly prescribed and most frequently abused opioid analgesics, yet little is known regarding individual vulnerabilities to oxycodone abuse. The synthetic cathinone 3,4-methylenedioxypyrovalerone (MDPV) has been shown to produce a “high-responder” phenotype characterized by increased drug intake and responding during periods of signaled drug unavailability (e.g., during post-infusion timeouts) in ~ 40% of male Sprague-Dawley rats. This phenotype also transfers to other psychostimulants (e.g., cocaine and methamphetamine), but it is unknown whether this phenotype transfers to other (non-stimulant) drugs of abuse. The present study aimed to (1) reestablish the “high-responder” phenotype in male Sprague-Dawley rats (n = 11) that acquired self-administration of MDPV (0.032 mg/kg/inf) on a fixed ratio 1 (FR1) schedule of reinforcement and (2) compare full dose-response curves for MDPV and oxycodone self-administration under an FR5 schedule of reinforcement. MDPV was ~ 3-fold more potent at maintaining peak levels of behavior and resulted in greater overall drug intake than oxycodone. High levels of timeout responding were noted in a subset of rats that acquired MDPV self-administration (“high-responders”, n = 5), and the FR5 dose-response curve for MDPV was shifted upward for these rats relative to their “low-responder” (n = 6) counterparts. “High-responders” also self-administered more infusions of oxycodone under an FR5 schedule of reinforcement than “low-responders”; however, this was not coupled with increased levels of timeout responding. The present data suggest that a subset of individuals with a history of using synthetic cathinones may be particularly vulnerable to the abuse of oxycodone.
A path forward: professional development as a means to support personalised learning

The Every Student Succeeds Act (ESSA, 2015) highlighted technology-based personalised learning (PL) as a means of providing equitable learning experiences for all students. Many states have put for...
PBDE exposure and the association with testosterone, estrone and estradiol around the time of thelarche

Background: Polybrominated diphenyl ethers (PBDEs) are flame retardants, exposing humans primarily though diet, dust and inhalation. Higher levels of PBDEs have been associated with adverse health ...
A cooperative approach for treatment of Zenker's diverticulum

Symptomatic Zenker’s diverticulum management has evolved from an open intervention to an endoscopic management. At our center, both an otolaryngologist and a gastroenterologist are present in the operating room when treating these lesions. An intra-procedural consensus is reached to undergo either rigid endoscopy or flexible endoscopic diverticulotomy with ENT guidance. We evaluated the real-world efficacy with a cooperative gastroenterology–otolaryngology approach. Single-center retrospective study of patients who underwent a cooperative endoscopic diverticulotomy by a gastroenterologist and otolaryngologist at Cleveland Clinic Florida between 2012 and 2019. Demographic and clinical data, intra-procedural findings/complications, post-procedural symptoms, recurrence rate, and reintervention variables were extracted. Patients included in the study were > 17 years old, with symptomatic confirmed typical single Zenker’s diverticulum. 63 subjects were identified. Patients were predominantly males (63.5%) and white (84.1%), with mean age 73.5 years (53–95). Most subjects presented dysphagia (98.4%), mostly to solids (79.4%). Other demographic and clinical data are described in Table 1. The diverticula had a mean size of 36.3 mm. In 30.1% of the cases food debris was found during the procedure. The mean procedure length was 38.4 minutes. All cases were performed as outpatient. Technical success was achieved in all cases. Patients were followed for a mean of 3.24 months post-procedure. Clinical success was achieved in 92% subjects. One intra-procedural perforation was treated with endoclip. A cooperative endoscopic approach by gastroenterology and otolaryngology for symptomatic Zenker’s diverticulum management offered excellent technical and clinical success. This approach proved to be safe and effective.
Electron-phonon coupling between silicon vacancy centers and optomechanical crystals in diamond

We investigate diamond optomechanical crystals (OMCs) with implanted silicon vacancy (SiV) centers at cryogenic temperatures (T ~ 5K). Large strain fields per phonon in OMC mechanical modes, coupled with high SiV strain susceptibility, enables high electron- phonon coupling between SiV-OMC with cooperativity ~0.5 at 5K.
Options for Nonindigenous Species Control and Their Economic Impact on the Great Lakes and St. Lawrence Seaway: A Survey

Nonindigenous species (NIS) cause substantial economic and ecological problems in the United States and other countries with marine trade. Current legislation and regulations require mandatory ballast water exchange for those ships entering the Great Lakes. Due to the low compliance rate, and some inherent defects of legislation, the current status of NIS control is not very encouraging. Several technical and legislative options have been proposed to improve the efficiency of NIS control. The most promising methods include filtration with ultraviolet, heat, and ballast water exchange. No one method, however, can 100% effectively solve the NIS problem. Moreover, the mandatory requirements may induce modal shifts from marine to rail or truck mode on the Great Lakes, which may cause several adverse side effects on the economy and the environment. The decision problems for the cargo owners and the legislative body are also formulated.
Exploring trade-offs in frequency allocation in a transit network using bus route patterns: Methodology and application to large-scale urban systems

Abstract Transit agencies seek to allocate their limited operational budget and fleet optimally to service routes in order to maximize user benefits. The Transit Network Frequency Setting Problem formulation developed in this study effectively captures the coupling between the routes and their prevailing patterns, which may have different subsets of stops visited at different times of the day. The number of riders is elastic to the prevailing number of bus trips at a given stop, which is the combination of different pattern dispatch frequencies. As a result, the study bridges the gap between the operator’s perspective where the decision unit is the pattern schedule, and the user’s perspective, which perceives frequencies at the route level. Two main formulations are introduced. The first one maximizes the number of riders and the total waiting time savings under budget, fleet, policy headway and bus loading constraints; the second minimizes the net cost under fleet, policy headway, bus loading, minimum ridership and minimum waiting time savings constraints. In both formulations, pattern headways are the decision variables. Spatial and temporal heterogeneity of ridership elasticity with respect to headway is captured. The formulations are applied to a large-scale test network for the Chicago area. The results show that a win–win solution is possible where both ridership and waiting time savings are increased, while the net cost is decreased.
Simulated influences of Lake Agassiz on the climate of central North America 11,000 years ago

Eleven thousand years ago, large lakes existed in central and eastern North America along the margin of the Laurentide Ice Sheet. The large-scale North American climate at this time has been simulated with atmospheric general circulation models1,2, but these relatively coarse global models do not resolve potentially important features of the mesoscale circulation that arise from interactions among the atmosphere, ice sheet, and proglacial lakes. Here we present simulations of the climate of central and eastern North America 11,000 years ago with a high-resolution, regional climate model nested within a general circulation model. The simulated climate is in general agreement with that inferred from palaeoecological evidence. Our experiments indicate that through mesoscale atmospheric feedbacks, the annual delivery of moisture to the Laurentide Ice Sheet was diminished at times of a large, cold Lake Agassiz relative to periods of lower lake stands. The resulting changes in the mass balance of the ice sheet may have contributed to fluctuations of the ice margin, thus affecting the routing of fresh water to the North Atlantic Ocean. A retreating ice margin during periods of high lake level may have opened an outlet for discharge of Lake Agassiz into the North Atlantic. A subsequent advance of the ice margin due to greater moisture delivery associated with a low lake level could have dammed the outlet, thereby reducing discharge to the North Atlantic. These variations may have been decisive in causing the Younger Dryas cold event3,4.
Normalization of hematocrit in patients with end-stage renal disease on continuous ambulatory peritoneal dialysis: The role of erythropoietin

Observations were made retrospectively and prospectively over one year on all patients on continuous ambulatory peritoneal dialysis (CAPD) to determine the effect of this modality on the hematocrit. Serum erythropoietin and parathyroid hormone levels were measured. Within five months the hematocrit increased 47 to 127 percent up to normal in four of nine patients. Five others remained severely anemic. There was no significant difference in serum creatinine levels among the patients within one month of CAPD. The four patients who responded were anemic while on hemodialysis and other modalities of end-stage renal disease management prior to CAPD. The serum erythropoietin level in the four patients who responded was 9.0 mU/ml or greater with a mean of 28 mU/ml, whereas in those who did not respond it was 5.0 mU/ml or less with a mean of 3 mU/ml. Since uremic toxins in the middle molecule range have been postulated to be responsible for erythropoiesis suppression in end-stage renal disease, and in addition, insufficient erythropoietin production and the clearance of some middle molecular weight substances is six times greater with CAPD than with hemodialysis, it appears that CAPD can normalize the hematocrit in patients with end-stage renal disease who were anemic on other modalities with little or no change in serum creatinine, provided the remnant kidneys are capable of producing sufficient erythropoietin. Parathyroid hormone levels were higher in patients who responded than in patients who did not respond.
Cell rejuvenation and social behaviors promoted by LPS exchange in myxobacteria

Bacterial cells in their native environments must cope with factors that compromise the integrity of the cell. The mechanisms of coping with damage in a social or multicellular context are poorly understood. Here we investigated how a model social bacterium, Myxococcus xanthus, approaches this problem. We focused on the social behavior of outer membrane exchange (OME), in which cells transiently fuse and exchange their outer membrane (OM) contents. This behavior requires TraA, a homophilic cell surface receptor that identifies kin based on similarities in a polymorphic region, and the TraB cohort protein. As observed by electron microscopy, TraAB overexpression catalyzed a prefusion OM junction between cells. We then showed that damage sustained by the OM of one population was repaired by OME with a healthy population. Specifically, LPS mutants that were defective in motility and sporulation were rescued by OME with healthy donors. In addition, a mutant with a conditional lethal mutation in lpxC, an essential gene required for lipid A biosynthesis, was rescued by Tra-dependent interactions with a healthy population. Furthermore, lpxC cells with damaged OMs, which were more susceptible to antibiotics, had resistance conferred to them by OME with healthy donors. We also show that OME has beneficial fitness consequences to all cells. Here, in merged populations of damaged and healthy cells, OME catalyzed a dilution of OM damage, increasing developmental sporulation outcomes of the combined population by allowing it to reach a threshold density. We propose that OME is a mechanism that myxobacteria use to overcome cell damage and to transition to a multicellular organism.
Passive millimeter wave imaging sensor enhanced vision system

This paper describes the concept and development activities for a Passive Millimeter Wave Imaging Sensor System that offers significant safety benefits to world aviation. Made possible by recent technological breakthroughs, Passive Millimeter Wave (PMMW) imaging sensors provide visual-like images of objects within their fields of view even under low visibility conditions (e.g., fog, clouds, snow, sandstorms, and smoke) that would blind visual and infrared (IR) sensors. Unlike synthetic images (computer generated), the PMMW image is real and completely passive thus providing numerous advantages over competing technologies. The Boeing Company is member of a consortium developing an advanced, demonstrator version of a PMMW imaging sensor-identified as a 'camera' that, when front-mounted on an aircraft, will give images of the forward scene at a rare and quality sufficient to enhance aircrew vision and situational awareness under low visibility conditions. The characteristics of a PMMW image in a system baseline integrated with other flight avionics to form an Enhanced or Synthetic Vision System, is described. The results of a real-time simulator developed to perform pilot evaluations of the PWMM image are presented.
Utility and application of SEM in delineating cause–effect relationship between ambient pollutant and fetal birth outcome

The US Environmental Protection Agency has set air quality standards for six criteria pollutants based on threshold levels that could be hazardous to human health. Interest in the potential impact of prenatal exposure to these pollutants has increased; however, validity of modeling approaches has hindered research in this area. To address the methodological concerns of the previous studies, we introduce the utility of modeling exposure–outcome relationships in maternal and child health environmental research using the structural equation modeling framework. The dataset for this study comprised all live births in Hillsborough County, FL, covering the period from 1998 to 2007 inclusive. Vital records data were linked to the hospital discharge and vital statistic birth data for analysis. Additionally, local air pollution data were utilized. Out of 104,967 births, 8813 (rate = 8.4%) were born with low birth weight (LBW), 6757 infants were preterm birth (PTB) (rate = 6.4%), and 9575 (rate = 9.1%) were born small for gestational age (SGA). Our structural equation modeling approach indicated the following: (1) five of the six criteria pollutants had a positive contribution to the latent variable and (2) all the outcome variables (SGA, LBW, and PTB) had a positive relationship with the latent variable, thereby, suggesting an association between higher pollutant values and adverse birth outcomes. Copyright © 2014 John Wiley & Sons, Ltd.
Pharmacy Communication to Adolescents and Their Physicians Regarding Access to Emergency Contraception

OBJECTIVE: Emergency contraception (EC) is an effective pregnancy prevention strategy. EC is available without a prescription to those aged 17 years or older. The objective of this study was to assess the accuracy of information provided to adolescents and their physicians when they telephone pharmacies to inquire about EC. METHODS: By using standardized scripts, female callers telephoned 943 pharmacies in 5 US cities posing as 17-year-old adolescents or as physicians calling on behalf of their 17-year-old patients. McNemar tests were used to compare outcomes between adolescent and physician callers. RESULTS: Seven hundred fifty-nine pharmacies (80%) indicated to adolescent callers, and 766 (81%) to physician callers, that EC was available on the day of the call. However, 145 pharmacies (19%) incorrectly told the adolescent callers that it would be impossible to obtain EC under any circumstances, compared with 23 pharmacies (3%) for physician callers. Pharmacies conveyed the correct age to dispense EC without a prescription in 431 adolescent calls (57%) and 466 physician calls (61%). Compared with physician callers, adolescent callers were put on hold more often (54% vs 26%) and spoke to self-identified pharmacists less often (3% vs 12%, P < .0001). When EC was not available, 36% and 33% of pharmacies called by adolescents and physicians respectively offered no additional suggestions on how to obtain it. CONCLUSIONS: Most pharmacies report having EC in stock. However, misinformation regarding who can take EC, and at what age it is available without a prescription, is common. Such misinformation may create barriers to timely access. * Abbreviations: EC — : emergency contraception FDA — : Food and Drug Administration
B12 absorption by monkey intestine.

SummaryMaximal stimulation by intrinsic factor of B12 uptake by the small intestine of the rhesus monkey occurred in the low ileum. IF from human, hog, monkey and rat stimulated B12 absorption, while preparations from dog, guinea pig and frog did not.
The occurrence of cystinylglycine in blood plasma

Cystinylglycine has been identified as a minor ninhydrin-positive component of deproteinized blood plasma from human, bovine, rat and rabbit blood. The amount present in human blood plasma is approximately one-fifth of that of cystine and is not significantly correlated with age or with the cystine level.
New Paradigm for Allosteric Regulation of Escherichia coli Aspartate Transcarbamoylase.

For nearly 60 years, the ATP activation and the CTP inhibition of Escherichia coli aspartate transcarbamoylase (ATCase) has been the textbook example of allosteric regulation. We present kinetic data and five X-ray structures determined in the absence and presence of a Mg(2+) concentration within the physiological range. In the presence of 2 mM divalent cations (Mg(2+), Ca(2+), Zn(2+)), CTP does not significantly inhibit the enzyme, while the allosteric activation by ATP is enhanced. The data suggest that the actual allosteric inhibitor of ATCase in vivo is the combination of CTP, UTP, and a divalent cation, and the actual allosteric activator is a divalent cation with ATP or ATP and GTP. The structural data reveals that two NTPs can bind to each allosteric site with a divalent cation acting as a bridge between the triphosphates. Thus, the regulation of ATCase is far more complex than previously believed and calls many previous studies into question. The X-ray structures reveal that the catalytic chains undergo essentially no alternations; however, several regions of the regulatory chains undergo significant structural changes. Most significant is that the N-terminal region of the regulatory chains exists in different conformations in the allosterically activated and inhibited forms of the enzyme. Here, a new model of allosteric regulation is proposed.
Spiritual well-being among outpatients with cancer receiving concurrent oncologic and palliative care

Purpose Spiritual well-being is threatened by cancer, but its correlation with other illness symptoms and the efficacy of palliative care (PC) to ameliorate spiritual suffering are not well understood.
Enhanced Effector Responses in Activated CD8+ T Cells Deficient in Diacylglycerol Kinases

Recent clinical trials have shown promise in the use of chimeric antigen receptor (CAR)-transduced T cells; however, augmentation of their activity may broaden their clinical use and improve their efficacy. We hypothesized that because CAR action requires proteins essential for T-cell receptor (TCR) signal transduction, deletion of negative regulators of these signaling pathways would enhance CAR signaling and effector T-cell function. We tested CAR activity and function in T cells that lacked one or both isoforms of diacylglycerol kinase (dgk) expressed highly in T cells, dgkα and dgkζ, enzymes that metabolize the second messenger diacylglycerol (DAG) and limit Ras/ERK activation. We found that primary murine T cells transduced with CARs specific for the human tumor antigen mesothelin showed greatly enhanced cytokine production and cytotoxicity when cocultured with a murine mesothelioma line that stably expresses mesothelin. In addition, we found that dgk-deficient CAR-transduced T cells were more effective in limiting the growth of implanted tumors, both concurrent with and after establishment of tumor. Consistent with our studies in mice, pharmacologic inhibition of dgks also augments function of primary human T cells transduced with CARs. These results suggest that deletion of negative regulators of TCR signaling enhances the activity and function of CAR-expressing T cells and identify dgks as potential targets for improving the clinical potential of CARs.
Synopsis of discussion III

Drs. Li and Hertz recalled the experience of the first three patients originally reported in whom intravenous administration of methotrexate was carried out in association with Dr. Paul Condit. After the first three patients, intramuscular and oral administration of the drug was used in attempts to prolong the blood levels attained. Dr. Hertz pointed out that following intramuscular administration it takes from 1 to 3 weeks for substantial reduction of gonadotropin titer to occur whereas earlier fall occurred following intravenous administration. He speculated this might be related to an artifactual effect of methotrexate on urinary excretion of chorionic gonadotropin, although better chemotherapeutic effect of the drug by intravenous administration in higher dose was not excluded.
Nicotine-induced embryonic malformations mediated by apoptosis from increasing intracellular calcium and oxidative stress.

BACKGROUND: Tobacco smoking by women during pregnancy increases the risk of congenital birth defects in the infants. Among the smoke products, nicotine is believed to be the major teratogenic factor that perturbs embryonic development. However, the role of nicotine in embryonic malformations has not been addressed, and the mechanisms by which nicotine affects embryonic development remain to be delineated. METHODS: To investigate the effects of nicotine on early embryogenesis, murine embryos at embryonic day (E) 8.5 were dissected out of the uteri, cultured in a roller bottle system, and treated with nicotine (0.6–6 µM) or vehicle. Embryonic morphogenesis and growth were examined in terms of structural morphology and crown/rump length, respectively. Programmed cell death (apoptosis) was assessed using LysoTracker Red staining of whole mount embryos and TUNEL assay of tissue sections. Changes in intracellular calcium concentration ([Ca2+]i) and reactive oxygen species (ROS) production were assessed using fluorescent dyes (Flu-4, AM; H2DCFDA, respectively) under a confocal microscope. To further investigate the role of intracellular calcium and ROS in nicotine-induced embryopathy, embryos were treated with BAPTA-AM (2 µM) to inhibit [Ca2+]i elevation and ascorbic acid (vitamin C; 100 µg/ml) to scavenge ROS in presence of nicotine (6 µM). RESULTS: The embryos treated with nicotine in 3–6 µM were smaller than those treated with vehicle. Most of the embryos had open neural tube in the anterior (brain) regions. The embryos treated with 6 µM nicotine also exhibited severe defects in the posterior trunk, resembling caudal dysplasia. Excessive apoptosis was observed in the deformed structures. Significant increases in [Ca2+]i and ROS were seen in the tissues that had higher levels of apoptosis. Furthermore, inhibition of [Ca2+]i and scavenging of ROS significantly reduced embryonic malformation and apoptotic rates in the embryos. CONCLUSIONS: Nicotine affects embryonic development in a concentration-dependent manner. The nicotine-induced embryonic malformations are, in part, a result of excessive cell death. Nicotine increases [Ca2+]i and ROS level, which play a role in nicotine-induced embryonic apoptosis and malformations. These studies identify the molecular pathway of nicotine action in embryonic apoptosis and malformations, and provide a promising approach for ameliorating the teratogenic effects of nicotine. Birth Defects Research Part B 2005. © 2005 Wiley-Liss, Inc.
Early life experiences affect adult delayed-type hypersensitivity in short and long photoperiods.

Environmental experiences during development provide animals with important information about future conditions. Siberian hamsters are photoperiodic rodents that dramatically adjust their physiology and behavior to adapt to seasonal changes. For example, during short winter-like days, hamsters enhance some components of immune function putatively to cope with increasing environmental challenges. Furthermore, early life stress alters the developmental course of the immune system. Overall, immune function is typically suppressed in response to chronic stress, but responses vary depending on the type of stress and components of immune function assessed. This led us to hypothesize that delayed-type hypersensitivity (DTH), an antigen-specific, cell-mediated immune response, would be differentially modulated in hamsters that underwent early life maternal separation (MS) in either short or long photoperiods. At birth, hamsters were assigned to either short (SD; 8 h light/day) or long (LD; 16 h light/day) photope...
Habitat modification inhibits conspecific seedling recruitment in populations of an invasive ecosystem engineer

Invasive species that strongly modify their physical habitat are a particular management concern. Theoretical models predict that habitat modification could speed spread rates or allow invasion of sites that would otherwise resist invasion. There are few empirical tests of this hypothesis, however. We tested whether habitat modification by invading Spartina alterniflora populations facilitates conspecific seedling recruitment and spatial spread in Willapa Bay, WA, USA. Established S. alterniflora individuals strongly modified their local physical environment. Hydrologic flow, porewater salinity, and light availability were decreased while sediment NH4 + increased with increasing S. alterniflora stem density. The S. alterniflora seed bank was greater and spring seedlings were denser within meadows of S. alterniflora than on unvegetated tideflats. However, almost all seedling recruitment after 1 year occurred on tideflats or on meadow edge plots where the above ground S. alterniflora biomass had been removed. Instead of facilitating invasive spread, ecosystem engineering in this system appears to create conditions that inhibit local seedling recruitment. These results suggest that the influence of ecosystem engineering on invasive spread is highly contingent on the relative spatial scales of habitat modification, environmental heterogeneity, and propagule availability. Control activities could change these spatial relationships, however, inadvertently promoting invasive recruitment.
Hysteresis Effects on Thrust Measurement and its Uncertainty

The work detailed herein describes a combination of experiments and numerical analysis meant to explore potential causes of both errors and hysteresis in a thrust measurement system and how they affect data reduction and uncertainty estimation. An uncertainty estimate of average hybrid motor thrust is also demonstrated. There were two major conclusions of this effort. First, hysteresis evident in a hybrid rocket motor test stand was eliminated through proper motor and thrust measurement system alignment. Second, Monte Carlo simulations showed that not including an elemental uncertainty contribution for hysteresis in an otherwise rigorous uncertainty propagation is a valid engineering approximation, when the experimental result is the average of data containing small (percentagewise) fluctuations.
Optical detection of the superconducting proximity effect: Raman scattering on Nb/InAs

Raman scattering on InAs coated with 60 to 100A thick Nb films (Tc=2.5 to 5K) is studied. The Nb films, sputtered ontoin-situ ion-etched n+-InAs (1.2×1019cm−3) are flat to ∼5A. The low-frequency coupled plasmon-phonon Raman mode (L_) associated with bulk InAs is centered at 221 cm−1. The forbidden LO phonon at 237cm−1, associated with the surface charge accumulation region (CAR), is observed because the thickness of the surface CAR is less than the Thomas-Fermi screening length. As the temperature is reduced below Tc the magnitude of the LO phonon mode intensity, relative to that of the L_mode, increases by more than 40%
The influence of halocarbon solvent on macrocycle-mediated cation transport through liquid membranes

Abstract Models which describe the macrocycle-mediated flux of cations through bulk liquid membranes indicate that membrane solvent exerts an important influence on membrane performance. Specifically, four of the parameters which determine flux are solvent dependent: the equilibrium constant for cation—macrocycle interaction in the membrane, the thickness of the unstirred boundary layers in the membrane, the partition coefficients, and the diffusivities of the species present. The series of halocarbons dichloromethane, trichloromethane, tetrachloromethane, 1,2-dichloroethane, 1,1,2-trichloroethane and 1,1,2,2-tetrachloroethane were used as membrane solvents in otherwise identical experiments. The macrocycle used was dicyclohexano-18-crown-6. The relative fluxes of Na + , K + , Rb + , Cs + , Ca 2+ , Sr 2+ , and Ba 2+ were determined and found to have distinctive patterns with changing solvent, with monovalent and divalent cations each demonstrating similar behavior. These trends are discussed in terms of various physical properties of the solvents involved.
CORRUPTION THEORY AND PRACTICE

Corruption is a very widespread phenomenon with most governments having a least some. While corruption usually meets with disapproval, it may have some redeeming features. It may make possible smaller or no salary payments to officials who, if carefully supervised, will still carry out their functions on a fee-for-service basis. The purchase of government jobs usually is thought to be corrupt, but in some cases, it has worked out quite well.
Effective-impurity model of optical absorption edges☆

A simple model of an amorphous or disordered semiconductor is presented in which the disorder is approximated by a distribution of effective impurities. In this model the disorder potential in a given region of the semiconductor is characterized by an effective charge, and the optical absorption in that region is calculated. The total absorption is then a statistical average (over effective charge distributions) of the absorption in the presence of a single effective-impurity. Thus the model leads to an expression for e2(ω) as a functional of the density-of-states, which accounts for electron-hole correlations due to both the final-state (exciton) interaction and the spatial fluctuations of the disorder potential. These effects lead to an exponential suppression of the optical absorption in the edge region, beyond that calculated in an uncorrelated non-direct transition model. Finally, the model is complementary to Franz-Keldysh theories of absorption edge shapes and can be used to describe exponential edges in a variety of non-conducting materials.
Residual tRNA secondary structure in ‘denaturing‘ 8M urea/TBE polyacrylamide gels: effects on electrophoretic mobility and dependency on prior chemical modification of the tRNA

Fifteen individual species of tRNA were treated with the chemical modifiers diethylpyrocarbonate, 50% aqueous hydrazine or hydrazine/3 M NaCl. Following purification of the chemically modified material on polyacrylamide gels containing 8 M urea, variant minor bands, in addition to the expected main band, were observed for 12 of the 15 tRNAs. Characterization of the content of chemically altered bases in material recovered from such bands indicated that tRNAs containing modified nucleotides in base-paired stems were excluded from the main band and present, often in enhanced amounts, in the minor variant bands. The persistence of residual secondary structure on 8 M urea gels run at 45 degrees C and the ability of chemically modified bases to alter electrophoretic mobilities warrant caution in designing and interpreting experiments in which chemically modified RNA is isolated on gels prior to further analysis. tRNA(Val) (VAC) was unique in that modified bases in non base-paired regions, according to the cloverleaf model of secondary structure, caused exclusion from the main band. Consequently, we propose a secondary structure for partially denatured tRNA(Val) (VAC), in which these bases are located in double stranded regions of the molecule.
A tunable narrowband photon detector based on the Burstein-Moss shift

A tunable photon detector sensitive to only a narrow band of wavelengths is described. The detector's spectral response is the result of an optical filter based on the Burstein-Moss shift.
Information theoretic solutions for correlated bivariate processes

Abstract In a bivariate context, we consider ill-posed inverse problems with incomplete theoretical and data information. We demonstrate the use of information theoretic methods for information recovery for a range of under-identified choice problems with more unknowns than data points.
The effects of children's goal structures and performance feedback on mood, task choice, and task persistence

To assess the mediational influence of children's goal structures on mood, task choice, and task persistence, 10- to 12- yr old children (n=98) were randomly assigned to use either learning-oriented (self-referenced) achievement goals or performance-oriented (other-referenced) achievement goals during a rule-learning task. Half of the children in each goal condition were randomly assigned to receive success feedback while the other half received failure feedback. Consistent with the hypotheses, children's mood benefited not only from success feedback, but also from the adoption of learning goals. Furthermore, following failure feedback, children using learning goals sought more challenging problems for subsequent trials. Contrary to the hypothesis, children who adopted learning goals did not appear willing to persist longer than children who adopted performance goals. The clinical implications of achievement goals as cognitive mediators were discussed.
New clues about magnetosphere noise and black aurora

The noise sounds vaguely as if it emanates from the high-pitched chatter of tropical birds or wetted fingers rubbing along musical glasses. However, the auroral kilometric radiation (AKR)—a radio wave of about 540–550 kilohertz just below the AM radio band—emanates from Earth's magnetosphere 11,000–13,000 kilometers above the Earth's northern lights. Some researchers had proposed this as the likely origin for the noise three decades ago. However, scientists at the AGU Fall Meeting, held in San Francisco, California, said that new measurements made by instruments onboard the four spacecraft of the European Space Agency's (ESA) Cluster mission have confirmed this theory.
RNA interference screening identifies lenalidomide sensitizers in multiple myeloma, including RSK2

To identify molecular targets that modify sensitivity to lenalidomide, we measured proliferation in multiple myeloma (MM) cells transfected with 27 968 small interfering RNAs in the presence of increasing concentrations of drug and identified 63 genes that enhance activity of lenalidomide upon silencing. Ribosomal protein S6 kinase (RPS6KA3 or RSK2) was the most potent sensitizer. Other notable gene targets included 5 RAB family members, 3 potassium channel proteins, and 2 peroxisome family members. Single genes of interest included I-κ-B kinase-α (CHUK), and a phosphorylation dependent transcription factor (CREB1), which associate with RSK2 to regulate several signaling pathways. RSK2 knockdown induced cytotoxicity across a panel of MM cell lines and consistently increased sensitivity to lenalidomide. Accordingly, 3 small molecular inhibitors of RSK2 demonstrated synergy with lenalidomide cytotoxicity in MM cells even in the presence of stromal contact. Both RSK2 knockdown and small molecule inhibition downregulate interferon regulatory factor 4 and MYC, and provides an explanation for the synergy between lenalidomide and RSK2 inhibition. Interestingly, RSK2 inhibition also sensitized MM cells to bortezomib, melphalan, and dexamethasone, but did not downregulate Ikaros or influence lenalidomide-mediated downregulation of tumor necrosis factor-α or increase lenalidomide-induced IL-2 upregulation. In summary, inhibition of RSK2 may prove a broadly useful adjunct to MM therapy.
1-Propenyl 4,6-Q-Benzylidene-β-D-Mannopyranoside-2,3-Cyclic Sulfate: A Substrate for the Synthesis of [F-18] 2-Deoxy-2-Fluoro-D-Glucose

Abstract 1-Propenyl 4,6-Q-benzylidine-β-D-mannopyranoside-2,3-cyclic sulfate was prepared from methyl α-D-mannopyranoside. This compound reacts cleanly with tetramethylammonium fluoride, followed by add hydrolysis (2N HC1), to give 2-deoxy-2-fluoro-D-glucose. The reaction is suitable for use with the short lived radionuclide fluorlne-18 (t1/2,=110 minutes).
Paired stereoisomer model for quantifying receptor concentration in vivo.

Purpose: In vivo receptor imaging currently uses two main methodologies to quantify receptor concentration in the brain: Nonlinear regression and graphical analysis. The purpose of this article is to suggest an alternative set of operational procedures and analysis. The paired stereoisomer method (SM) combines elements of the two existing methodologies. It also takes advantage of a unique property of radiolabeled stereoisomer ligands, where the chemistry of the two isomers in the target tissue is identical with the exception of active binding to the receptor. Methods: Starting with a standard two-compartment model as an example, a set of operational equations is derived to evaluate a pair of PET/SPECT images of sequential radiolabeled ligand injections: One active, one inactive. The solution is derived in terms of an instantaneous and normalized supply term ( activity × time ) to more easily characterize model behavior. Also, a set of computer generated tissue curves for both rapid and prolonged plasma supply curves are generated. The data collection periods, needed to reach an accurate value for receptor concentration, are evaluated. An approximation to shorten the required data collection is developed and evaluated. The experimental requirements needed to obtain a matched pair of injections are discussed as well. Results: The SM method, given enough time to capture the area under the tissue curves, eliminates the large impact of flow and brain permeability to accurately estimate receptor concentration. The analysis also shows that the solution is independent of scanner calibration, works for inactive isomers that have reduced affinity as well as no affinity, works for mixtures of isomers with different affinities, and, finally, works for multicompartment models where the chemistry of the isomers differ only by active binding to receptor. Tissue curve analysis (computer generated) shows that the data collection time required is as fast as the slowest dynamic of the system being evaluated. The experimental practicalities in obtaining a matched pair of injections (scale each tissue curve with respect to the supply for that injection) vary from simple to tedious depending on the whole body biodistribution of the two radioligands. However, this measurement is always theoretically achievable given the ability to directly measure plasma levels. Conclusions: The SM method reduces the error from many of the assumptions required in the graphical analysis method. It is a promising approach which deserves to be tested against actual clinical data. The potential advantages are the reduction in random error by using area measurements as well as the reduction in bias error by eliminating assumptions/measurements of scanner calibration, reference regions, and assorted equilibrium conditions. These advantages offer the possibility of a method with easier implementation and improved accuracy for the clinicalin vivo measurement of receptor concentration.
Effect of surface temperature on the sorption of hydrogen by Pd(111)

Abstract Temperature programmed desorption (TPD) subsequent to various hydrogen exposure conditions indicates the formation of chemisorption, solid solution, and hydride phases of hydrogen in the near surface region of Pd(111). Variation of the sample exposure temperature (Te) between 80 and 300 K has a strong effect on the subsequent TPD spectra. At Te = 80 K a single desorption peak, β, appears at 310 K. Coverage variation of the β peak is consistent with second-order recombinative desorption of chemisorbed hydrogen. For Te between 90 and 140 K a slight enhancement of the β peak occurs and a new peak, α, appears initially near 170 K. It does not saturate, exhibits near-zeroth-order desorption kinetics, and is assigned to the decomposition of a near surface palladium hydride phase. Population of the α peak is thermally activated with a maximum at Te ≈ 115 K. For Te, greater than 140 K, α disappears while the total amount of absorbed hydrogen increases significantly. At these temperatures, the concentration of absorbed hydrogen decreases significantly if the sample is held in vacuo at Te after completion of the hydrogen exposure. At all exposure temperatures there is also a broad desorption feature near 800 K which is enhanced by higher Te and is associated with hydrogen in solid solution.
Ablative techniques for the management of kidney cancer

Probe-ablative techniques for small kidney cancer lesions are being investigated as alternatives to partial nephrectomy in selected patients. Advances in imaging guidance that are improving outcomes and the minimally invasive nature make this approach to therapy attractive. This Review provides a critical evaluation of the advantages and disadvantages of these techniques. For lesions smaller than 4 cm, nephron-sparing surgery has been shown to be oncologically equivalent to radical nephrectomy, albeit with the advantage of preservation of overall renal function. As such, partial nephrectomy became the first-line treatment option for localized, small renal masses. Minimally invasive options associated with limited morbidity—such as probe-ablative procedures—are, however, being investigated in selected patients for whom invasive, nephron-sparing surgery (whether laparoscopic or open) is undesirable. The main probe-ablative techniques being investigated as alternatives to partial nephrectomy are cryoablation, radiofrequency ablation, and high-intensity focused ultrasound. Advances in imaging, ablative system technologies, and early evidence that in situ tumor ablation can yield comparable results to those achieved with tumor resection in selected cases, have sparked significant interest in these minimally invasive techniques.
Push enteroscopy is superior to small bowel follow-through in the evaluation of iron deficiency anemia

Push enteroscopy is superior to small bowel follow-through in the evaluation of iron deficiency anemia
Attentional resources in timing: Interference effects in concurrent temporal and nontemporal working memory tasks.

Three experiments examined interference effects in concurrent temporal and nontemporal tasks. The timing task in each experiment required subjects to generate a series of 2- or 5-sec temporal productions. The nontemporal tasks were pursuit rotor tracking (Experiment 1), visual search (Experiment 2), and mental arithmetic (Experiment 3). Each nontemporal task had two levels of difficulty. All tasks were performed under both single- and dual-task conditions. A simple attentional allocation model predicts bidirectional interference between concurrent tasks. The main results showed the classic interference effect in timing. That is, the concurrent nontemporal tasks caused temporal productions to become longer (longer productions represent a shortening of perceived time) and/or more variable than did timing-only conditions. In general, the difficult version of each nontemporal task disrupted timing more than the easier version. The timing data also exhibited a serial lengthening effect, in which temporal productions became longer across trials. Nontemporal task performance showed a mixed pattern. Tracking and visual search were essentially unaffected by the addition of a timing task, whereas mental arithmetic was disrupted by concurrent timing. These results call for a modification of the attentional allocation model to incorporate the idea of specialized processing resources. Two major theoretical frameworks—multiple resource theory and the working memory model—are critically evaluated with respect to the resource demands of timing and temporal/ nontemporal dual-task performance.