cssi/SciSciGPT-SciSciNet huggingface dataset:
Robotic Technologies (Past, Present and Future)

Today’s surgeon has access to a growing quiver of robotic technology aimed at both increasingly specialized procedures and broad applications. The availability and array of options for robotic-assisted surgery has seen exponential growth in recent times. Systems incorporate tactile haptic feedback, stereoscopic visualization, high definition three-dimensional display, and multisensory inputs. Existing platforms are comprised of iterations bred from research and development efforts across millennia and seek to improve nearly every facet of the physician-patient interaction.
5PSQ-001 Pharmacist intervention to improve the safety of patients treated with proton pump inhibitors

Background and importance The use of proton pump inhibitors (PPIs) to treat acid related disorders is increasing worldwide and this raises concerns. Accumulating evidence supports the increased risk of long term adverse events, such as fractures, chronic kidney disease (KD), hypomagnesaemia, Clostridium difficile infections, associated with chronic PPI use. Aim and objectives The aim of the study was to describe the results of a pharmacist intervention to improve the safety of hospitalised patients receiving treatment with PPIs. Material and methods A prospective study was conducted from July to September 2019 in a tertiary care hospital. We included all hospitalised patients with active prescriptions for PPIs and presenting with hypomagnesaemia, KD and C difficile associated diarrhoea. In these cases, a message containing a safety note from the ‘Agencia Espanola de Medicamentos y Productos Sanitarios’ was reflected in the electronic prescribing software application. The following data were collected from the electronic health records: sex, age, hospital unit, adverse events associated with PPI use, pharmacist intervention acceptance (yes/no) and subsequent modification of the prescription by physicians. Results We included 55 patients (21 women) with a mean age of 67 years (range 24–91). The main prescription units were: internal medicine (25.9%), nephrology (18.5%), haematology (11.1%), digestive (9.25%) and surgery (9.25%). Around 70.9% of patients (n=39) presented with hypomagnesaemia, 21.8% (n=12) with KD, 3.6% (n=2) with C difficile infections and 3.6% (n=2) had C difficile associated diarrhoea and hypomagnesaemia. In total, 55 interventions were carried out, 16 of them (29.1%) were accepted and the treatment was modified by the physicians as follows: ranitidine was prescribed in 15 cases (instead of PPI), 13 because of hypomagnesaemia and 2 due to KD; and the PPIs posology was modified in 1 patient with KD. Conclusion and relevance Most patients identified were hospitalised in the internal medicine unit, and hypomagnesaemia was the most common event adverse. The acceptance rates for this pharmacist intervention was moderate. It is necessary to continue with the distribution of safety notes and medication review in order to avoid potential adverse effects. References and/or acknowledgements No conflict of interest.
Determination of atrazine in vegetables by magnetic molecularly imprinted polymer flow injection preconcentration and gas chromatography

Objective A method for rapid determination of atrazine in vegetables by gas chromatography based on magnetic molecular imprinting technology in flow injection system was established. Methods Core-shell magnetic molecularly imprinted polymers were prepared using ferroferric oxide modified with chitosan as the carrier, atrazine as the template, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. The attraction of the imprinted polymers for atrazine was studied through static equilibrium binding. The atrazine in the sample were extracted with ethyl acetate and then cleaned-up with MIPs SPE cartridges. The target molecules were eluted by methanol and then quantitatively determined by gas chromatograph. Results The maximum adsorption capacity was 52. 0 mg/g. Under the optimal conditions, the linearity of the method obtained was 5-100 μg/L. The detection limits of atrazine was 0. 6 μg/kg. The recoveries were between 81. 5% and 107. 7%(n=6). Conclusion The proposed method is successfully applied to determine atrazine in vegetables.
Powering Africa by Photovoltaics

In this paper we have presented the technical and economic aspects of powering Africa by photovoltaics. The low cost of photovoltaic system and batteries will go a long way in alleviating African nations from energy poverty and from global poverty. The transportation will benefit the environment since carbon emission intense vehicles will be replaced by electric vehicles. In addition, access to clean and potable water will be possible from the deployment of low-cost direct current (DC) powered electricity infrastructure. In most places, local power network based on DC power will be practical and in case of long-haul transmission, DC high voltage transmission should be used. Development of high efficiency appliances based on DC power will be extremely beneficial to the world. Financing of manufacturing base and new electricity infrastructures should be majorly financed by world financial institutions like the United Nations, International Monetary Fund, World Bank, and major charitable organizations.
Estimating heat storage in urban areas using multispectral satellite data and machine learning

Abstract A satellite-derived hysteresis model is presented for estimate heat storage in urban areas. Storage heat flux, one of the dominant terms in the urban surface energy budget (USEB), is largely unknown despite its critical relationship to various urban environmental processes. This study introduces a novel technique for quantifying heat storage by relating multispectral satellite radiances and geophysical properties to ground-truth residual heat storage computed with flux instruments. Gradient-boosted regression trees serve as the method of maximizing the relationship between satellite data and flux measurements. Several flux networks are used to train and validate the model over varying land cover types, which strengthens the robustness of the model. The model performs well under variable weather conditions such as cloudy rainy days. In comparison with other studies, the RMSE and MAE values were found to be lower than some ground-to-ground studies, and is one of few satellite-derived methods that computes direct comparison over a range of different land cover types.
Is photoperiod a dominant driver of secondary growth resumption

In their recent paper, Huang et al. (1) have amassed a fascinating time-series of xylem tissue formation across 826 individual trees, spanning 21 species and 79 Northern Hemisphere locations. Like many other aspects of plant growth, wood formation shows strong seasonality, but very little is known about the environmental triggers for seasonal growth resumption. With wood absorbing ∼15% of anthropogenic CO2 emissions annually, this extensive dataset provides an exciting opportunity to refine earth system models, but it does not provide compelling evidence that photoperiod is the dominant season cue. The crux of Huang et al.’s conclusions are derived from their observed positive relationship between the day of year of wood formation (DOYwf) and the photoperiod on the day of year of wood formation (Photoperiodwf), using an analysis that relies heavily on R 2 values (ref. 1, figures 3, S5, and S7). The authors used the response variable (DOYwf) to calculate several of their predictor variables: Photoperiodwf, cumulative forcing (FUwf), and chilling (CUwf) at DOYwf. There are two major problems with this approach. First, it can lead to regression models that appear to fit exceptionally well for the wrong reasons. Where photoperiod covaries positively with day of … [↵][1]1To whom correspondence may be addressed. Email: sarah.elmendorf{at}colorado.edu. [1]: #xref-corresp-1-1
Social and Leisure Activity Contribute to the Attenuation of Decline in Behavioral Variant Frontotemporal Degeneration

ABSTRACT Behavioral variant frontotemporal degeneration (bvFTD) is clinically characterized by progressive decline in social and executive domains. Previous work suggests that early lifestyle factors such as education and occupational attainment may relate to structural integrity and moderate the rate of cognitive decline in bvFTD, but the role of other cognitively stimulating activities is understudied. We sought to investigate the effect of such activities on cortical thickness (CT) in bvFTD. bvFTD patients (n=31) completed a baseline MRI scan, and informants for the patients completed the Lifetime of Experiences Questionnaire (LEQ), which measures specific activities considered to be undertaken primarily within one particular life phase, such as education (young-life), occupation (mid-life), and social/leisure activity (late-life). At baseline, linear models assessed the effect of LEQ scores from each life phase on regional CT. A subset (n=19) of patients completed longitudinal MRI, and to evaluate the association of LEQ with longitudinal rates of CT decline, we derived individualized slopes of decline using linear mixed effects models and these were related to LEQ scores from each life phase. At baseline, a higher late-life LEQ score was associated with less atrophy in bilateral superior anterior temporal regions. Longitudinally, we observed that higher late-life LEQ scores were associated with an attenuated rate of CT loss in insular cortex. Late-life LEQ score was positively associated with both relatively preserved CT early in bvFTD and a slower rate of cortical loss in regions important for social functioning. These findings suggest that social and leisure activities may contribute to a form of resilience against pathologic effects of disease.
Water distribution network function and centrality

Modeling water distribution networks facilitates assessment of system resiliency, improvements for demand forecasting, and overall optimization of limited system resources. This report serves as an introduction to the fundamentals of Water Distribution Networks (WDN) and provides insight into modern approaches of modeling these critical infrastructures. We provide an overview of core components within a WDN and a literature review and summary of current modeling approaches. We investigate and compare three unique vulnerability assessment methodologies based upon a graph theoretic approach. We assess the merits of each approach and the associated analytics implemented to identify the critical nodes and edges within a network. The first method utilizes a topological approach and segments the network into valve-enclosed sections. Analysis is centered on a depth-first search to identify nodes which would impact the most downstream nodes. The second method fuses topological and hydraulic data calculated using software such as EPANET. Various centrality measures corresponding to portion of network flow are used to assess vulnerability. The last method focuses on pipe (edge) vulnerability, incorporating information such as the average daily flow through each pipe as key parameters to algorithmically assess vulnerability.
Critical role of pathology and laboratory medicine in the conversation surrounding access to healthcare

Pathology and laboratory medicine are a key component of a patient’s healthcare. From academic care centres, community hospitals, to clinics across the country, pathology data are a crucial component of patient care. But for much of the modern era, pathology and laboratory medicine have been absent from health policy conversations. Though select members in the field have advocated for an enhanced presence of these specialists in policy conversations, little work has been done to thoroughly evaluate the moral and ethical obligations of the pathologist and the role they play in healthcare justice and access to care. In order to make any substantive improvements in access to care, pathology and laboratory medicine must have a seat at the table. Specifically, pathologists and laboratorians can assist in bringing about change through improving clinician test choice, continuing laboratory improvement programmes, promoting just advanced diagnostic distribution, triage testing and be good stewards of healthcare dollars, and recruiting a more robust laboratory workforce. In order to get to that point, much work has to be done in pathology education and the laboratory personnel training pipeline but there also needs to be adjustments at the system level to better involve this invaluable group of specialists in these policy conversations.
Fluorescence lifetime imaging microscopy and time-resolved anisotropy of nanomaterial-induced changes to red blood cell membranes.

With the use of engineered nano-materials (ENM) becoming more prevalent, it is essential to determine potential human health impacts. Specifically, the effects on biological lipid membranes will be important for determining molecular events that may contribute to both toxicity and suitable biomedical applications. To better understand the mechanisms of ENM-induced hemolysis and membrane permeability, fluorescence lifetime imaging microscopy (FLIM) was performed on human red blood cells (RBC) exposed to titanium dioxide ENM, zinc oxide ENM, or micron-sized crystalline silica. In the FLIM images, changes in the intensity-weighted fluorescence lifetime of the lipophilic fluorescence probe Di-4-ANEPPDHQ were used to identify localized changes to membrane. Time-resolved fluorescence anisotropy and FLIM of RBC treated with methyl-s-cyclodextrin was performed to aid in interpreting how changes to membrane order influence changes in the fluorescence lifetime of the probe. Treatment of RBC with methyl-s-cyclodextrin caused an increase in the wobble-in-a-cone angle and shorter fluorescence lifetimes of di-4-ANEPPDHQ. Treatment of RBC with titanium dioxide caused a significant increase in fluorescence lifetime compared to non-treated samples, indicating increased membrane order. Crystalline silica also increased the fluorescence lifetime compared to control levels. In contrast, zinc oxide decreased the fluorescence lifetime, representing decreased membrane order. However, treatment with soluble zinc sulfate resulted in no significant change in fluorescence lifetime, indicating that the decrease in order of the RBC membranes caused by zinc oxide ENM was not due to zinc ions formed during potential dissolution of the nanoparticles. These results give insight into mechanisms for how these three materials might disrupt RBC membranes and membranes of other cells. The results also provide evidence for a direct correlation between the size, interaction-available surface area of the nano-material and cell membrane disruption.
DNA electrical properties and potential nano-applications

This paper reviews research results on DNA electrical properties and proposes potential nano-applications of the electrical properties.
J. M. Cooper (Ed.), Reconsidering Woodrow Wilson: Progressivism, Internationalism, War, and Peace

The dozen substantive essays that comprise this fine volume were originally delivered at an October 2006 conference marking the sesquicentennial of Woodrow Wilson's birth. Lest readers question the...
Functional Interaction of ADP-ribosylation Factor 1 with Phosphatidylinositol 4,5-Bisphosphate

The relationship between ADP-ribosylation factor (Arf) 1 and phosphoinositides, which have been independently implicated as regulators of membrane traffic, was examined. Because both Arf-dependent phospholipase D and Arf1 GTPase-activating protein (GAP) require phosphatidylinositol 4,5-bisphosphate (PIP2), Arf1 complexed with PIP2 has been proposed to interact with target proteins. This hypothesis was tested using Arf1 GAP as a model system. Arf1 was shown to bind to PIP2 in Triton X-100 micelles with a Kd of 45 +/- 13 microM. Arf1 also bound phosphatidic acid but with 10-fold lower affinity. PIP2 binding was specifically disrupted by mutating lysines 15, 16, and 181 and arginine 178 to leucines. Decreased PIP2 binding resulted in an increased EC50 of PIP2 for activation of Arf GAP. None of the mutations that decreased PIP2 binding affected binding to or activation of GAP by phosphatidic acid, which acts at a functionally distinct site. These data support the hypothesis that PIP2 binding to Arf1 promotes interaction with Arf GAP. The implications of lipid-directed protein-protein interactions for membrane traffic are discussed.
Performance evaluation of the spectral centroid downshift method for attenuation estimation

Estimation of frequency-dependent ultrasonic attenuation is an important aspect of tissue characterization. Along with other acoustic parameters studied in quantitative ultrasound, the attenuation coefficient can be used to differentiate normal and pathological tissue. The spectral centroid downshift (CDS) method is one the most common frequencydomain approaches applied to this problem. In this study, a statistical analysis of this method’s performance was carried out based on a parametric model of the signal power spectrum in the presence of electronic noise. The parametric model used for the power spectrum of received RF data assumes a Gaussian spectral profile for the transmit pulse, and incorporates effects of attenuation, windowing, and electronic noise. Spectral moments were calculated and used to estimate second-order centroid statistics. A theoretical expression for the variance of a maximum likelihood estimator of attenuation coefficient was derived in terms of the centroid statistics and other model parameters, such as transmit pulse center frequency and bandwidth, RF data window length, SNR, and number of regression points. Theoretically predicted estimation variances were compared with experimentally estimated variances on RF data sets from both computer-simulated and physical tissue-mimicking phantoms. Scan parameter ranges for this study were electronic SNR from 10 to 70 dB, transmit pulse standard deviation from 0.5 to 4.1 MHz, transmit pulse center frequency from 2 to 8 MHz, and data window length from 3 to 17 mm. Acceptable agreement was observed between theoretical predictions and experimentally estimated values with differences smaller than 0.05 dB/cm/MHz across the parameter ranges investigated. This model helps predict the best attenuation estimation variance achievable with the CDS method, in terms of said scan parameters.
Idiopathic dilatation of the common bile duct in children

Summary Fifty-two cases of idiopathic choledochus cyst in childhood are reviewed. Two of these cases are reported for the first time. The more important symptoms and signs are usually characteristic and consist of abdominal pain, abdominal tumor, and jaundice. The size and tenseness of the abdominal tumor in a given case may vary from time to time. Acholic stools may be present and there may be bile in the urine. The average duration of symptoms was about three years. In approximately one-half of the cases the symptoms had been intermittent and had occurred in attacks with intervening periods of remission. About three-fourths of the patients were females. The correct diagnosis was made only three times before operation, but the nature of the history and the physical findings should enable the diagnosis to be made more frequently. The important pathologic finding is a large cystic dilatation of the common duct. In one-half of the cases there was an angulation, stenosis, obliteration, or valve formation at the cyst outlet, but many of these conditions were probably the result of rather than the cause of the common duct enlargement. The liver was practically always enlarged and biliary cirrhosis and cholangitis were common. The etiology of the condition has not been definitely determined, but many theories have been advanced. The common duct dilatation is most likely a result of congenital weakness of the duct wall which is not productive of enlargement until there is obstruction to the flow of bile. Such obstruction may be from congenital stenosis, valve formation, angulation, or cholangitis of the lower common duct. The accepted form of treatment is to anastomose the biliary and the intestinal tracts at one operation, the most acceptable method of doing this being the production of a choledochoduodenostomy. The mortality in the entire group of 52 patients was 69 per cent, but in those treated by primary anastomosis of biliary tract and intestine the mortality was 9 per cent.
Two New β-strand Mimics

Abstract In a previous report, Nowick and co-workers described β-strand mimic A , which duplicates the structure and hydrogen-bonding pattern of one edge of a tetrapeptide in a β-strand conformation (Nowick, J. S.; Pairish, M.; Lee, I. Q.; Holmes, D. L.; Ziller, J. W. J. Am. Chem. Soc. 1997 , 119 , 5413). β-Strand mimic A is composed of a 5-amino-2-methoxybenzoic acid unit linked to a 5-hydrazino-2-methoxybenzamide unit by means of an acylhydrazine group. This paper introduces two related β-strand mimics ( B and C ) and reports their comparison to β-strand mimic A . β-Strand mimic B is composed of a 5-amino-2-methoxybenzoic acid unit linked by a diacylhydrazine group to a fumaramide unit; β-strand mimic C is composed of a 5-amino-2-methoxybenzoic acid unit linked by a diacylhydrazine group to a peptide. β-Strand mimics A–C were connected to tripeptide (Phe-Ile-Leu) groups by means of 1,2-diaminoethane diurea turn units to form artificial β-sheets 1–3 . 1 H NMR studies, involving ROESY, chemical shift, coupling constant, and variable temperature experiments, reveal that 1–3 adopt hydrogen-bonded antiparallel β-sheet conformations and establish that all three templates are viable β-strand mimics.
Effects of Gossypol From Cottonseed on Hematological Responses and Plasma α-Tocopherol Concentration of Dairy Cows

Abstract The effects of feeding whole cottonseed (WCS) and bovine somatotropin (bST) administration on hematological responses and plasma α-tocopherol concentrations of lactating dairy cattle were examined. After parturition, multi and primiparous Holstein cows (n=159) were assigned randomly to a 2×2 factorial arrangement of treatments consisting of (0 or 15% WCS and 0 or 208mg of bST injected every 2 wk starting within 7 d after calving. Blood samples were collected from a subset group of 64 cows at 14, 28, 42, and 56 d postpartum. Blood was collected from all cows (n=159) at 75, 96 and 120 d postpartum. Blood samples were analyzed for α -tocopherol and total and (+)- and (−)-gossypol in plasma. Erythrocyte osmotic fragility, hemoglobin and hematocrit also were determined in blood. The mean concentrations of α -Tocopherol, total, and (+) - and (−) - gossypol were higher in cows fed WCS regardless of bST administration and plateaued by d 75 postpartum. Hematocrit and hemoglobin concentrations were not affected by treatments. Erythrocyte osmotic fragility was higher in cows fed WCS, but the increase was attenuated when bST was injected (diet×bST interaction). No clinical signs of gossypol toxicity were observed in the cows consuming the WCS.
Analysis of tocopherols and phytosterols in vegetable oils by HPLC with evaporative light-scattering detection

Methods were developed for the separation, detection, and quantification of tocopherols and phytosterols by high-performance liquid chromatography with an evaporative light-scattering detector. Four tocopherols— α, β, γ and δ—and four phytosterols—campesterol, β-sitosterol, brassicasterol, and stigmasterol—were analyzed in soybean, sunflower, low-erucic acid rapeseed (LEAR) and corn oils. The use of an evaporative light-scattering detector, in conjunction with modification of methods from the literature to prepare and analyze tocopherols and phytosterols by HPLC, showed consistent results between trials and levels of these minor constituents.
Combined effect of dorzolamide and latanoprost on the rate of aqueous humor flow

Abstract PURPOSE: To determine whether latanoprost, an ocular hypotensive agent believed to enhance uveoscleral outflow of aqueous humor, augments the aqueous-suppressing effect of dorzolamide, a topical carbonic anhydrase inhibitor. METHODS: Twenty-four normal subjects underwent measurement of aqueous humor flow by fluorophotometry to determine the flow with placebo, with dorzolamide, and with a combination of dorzolamide and latanoprost. RESULTS: The flow of aqueous humor was suppressed 13% by dorzolamide but not by latanoprost. Latanoprost did not augment the effect of dorzolamide on aqueous humor flow; latanoprost and dorzolamide had additive ocular hypotensive effects. CONCLUSIONS: The uveoscleral flow effect of latanoprost does not improve the aqueous-suppressing effect of dorzolamide, but the two drugs have additive ocular hypotensive effects.
Do real business cycle models really exhibit business cycle behavior

Abstract Previous research indicates that real business cycle models are capable of reproducing important features of U.S. business cycle behavior. Here I employ classical methods of business cycle analysis to determine how well the cyclical properties of simulated data from a representative real business cycle model match up with postwar U.S. business cycle characteristics. While the simulated model reproduces qualitative features consistent with observed business cycle experience, quantitative goodness-of-fit tests show that for many sectors of the economy the cyclical characteristics of the simulated data deviate significantly from U.S. business cycle experience.
Genetics of childhood disorders: XII. Genomic imprinting: breaking the rules.

Genomic imprinting refersto a process that distinguishes paternally derived chromosomes from maternally derived chromosomes. Imprinting plays a critical role in gene expression, mammalian development, and human disease. However, the biological requirement for imprinting remains a mystery. In the first 2 columns on the topic, we will reviewhow imprinting was initially identified, present some hypotheses about the mechanisms of imprinting, and speculate on the evolutionary forces maintaining this phenomenon. The subsequent 2 columns will discuss the molecular basesfor 2 disorders in which imprinting is involved, namely, Prader-Willi and Angelman syndromes. Genomic imprinting might be considered the exception that proves the rule. Until the late 1980s, Gregor Mendel's laws of inheritance were thought to be inviolate. All autosomal genes were believedto be expressedequally, regardless of whether they were inherited from the mother or the father. For most genes, this is true. However, it is now recognized that a small subset of genesareviolators of Mendel's lawsand are expresseddifferently depending on the parent from whom they are inherited. Genomic imprinting refers to the normal process whereby specificgenes or DNA segments are reversiblymodified during gametogenesis in a parent-specific fashion. Although research on exactlyhow this occurs is not yet understood, one modification that is believed to playa role is the reversible addition of methyl groups to specific cytosine residues within the DNA sequence, a process that occurs differently in generation of the egg and the sperm. Genomic imprinting is called an epigenetic phenomenon, since the gene structure-the actual sequence of nucleotides-is not affected as occurs during the mutations that were discussed in previous columns. Rather, the "imprint" is erased during gametogenesis and must be reapplied in a gender-specific manner. For example, in the normal situation, a methylated gene inherited by a male from his mother will be unmethylated during spermatogenesis, and this unmethylated gene, when passed on to his daughter, must be remethylated during oogenesis. As a result of this differential methylation, the maternally inherited copy of an imprinted DNA segment differs from the paternally inherited copy. What has recently been discovered is that these differences may also be reflected in differences in gene expression, even though the nucleotide sequences of the 2 segments are identical. The imprinting process leads to an inactivation of either the paternally or maternally inherited
ORGANIC GEOCHEMICAL COMPOSITION OF THE GEORGIA KAOLINS: INSIGHTS INTO FORMATION AND DIAGENETIC CONDITIONS

Most previous studies of the kaolin deposits in the southeastern United States have focused on their mineralogy and petrology to understand better the depositional and diagenetic environments of the kaolins. Many studies suggest, however, that much of the information held within the minerals was changed during extensive post-depositional groundwater and microbial alteration. Organic δ 13 C and biomarker analyses were used, therefore, to provide further information on the nature of the original sediments, the depositional environment(s), and the amount of diagenetic alteration that has occurred in Georgia kaolin deposits. Two different types of kaolin can be discerned, based on their total organic carbon contents: organic-lean kaolin and lignitic kaolin. The bulk organic δ 13 C in the Georgia kaolins ranges from ~−26 to −19‰ (VPDB, Vienna Pee Dee Belemnite standard), with a noticeable enrichment in 13 C with decrease in organic carbon concentration. The lean kaolins are by far the more dominant types, with an organic-matter composition primarily of C 16 –C 22 n -alkanes, C 16 and C 18 fatty acids, and unresolved complex mixtures. Lignitic kaolin has a distinctly different organic matter (OM) composition. The lignitic material is primarily C 15 –C 33 n -alkanes with a greater abundance of C 23 –C 31 n -alkanes and lesser amounts of resinous and microbial constituents along with the oxidized forms of the saturated lipid fractions. Biomarker data suggest that the lignitic material is primarily terrestrially derived from conifers with minor input from microbial lipids. The OM in both types of kaolin shows strong signs of microbial decomposition that yield the organically lean kaolins. The oxidation of the detrital organic matter would subsequently yield organic acids that would have exerted significant influence on the mineralogy and metal mobility.
Proton/hydroxide conductance through lipid bilayer membranes.

A simple method of measuring proton/hydroxide conductance (G H/OH) through planar lipid bilayer membranes is described. First the total conductance (G m ) is measured electrically. Then the H+/OH− transference number (T H/OH) is estimated from the diffusion potential (V m ) produced by a transmembrane pH gradient. The pH gradient is produced by a pair of buffered solutions which have identical concentrations of all ions except H+ and OH−. Thus,V m is due entirely to H+/OH− diffusion andG H/OH can be calculated from the relations,V m =T H/OH E H/OH andG H/OH=T H/OH G m , whereE H/OH is the equilibrium potential for H+ and OH−. In bilayers made from bacterial phosphatidylethanolamine (PE) inn-decane,G H/OH is nearly independent of pH, ranging from about 10−9 S cm−2 at pH 1.6 to 10−8 S cm−2 at pH 10.5. BecauseG H/OH is nearly independent of pH, the calculated permeability coefficients to H+ and/or OH− are extremely pH dependent, which partly explains the wide range of values reported for phospholipid vesicles and biological membranes.G H/OH appears to be independent of the membrane surface charge, because titrating either the phosphate or the amino group of PE has little effect onG H/OH.G H/OH is reduced about 10-fold when the water activity is reduced 33% by replacement with glycerol. Although the mechanism of H+/OH− conductance is not known, the relation betweenG H/OH and water activity suggests that several water molecules are involved in the H+/OH− transport process.
Marking Xs, together and separately.

A chromosome imprinting mark is sensitive to meiotic pairing in the gamete of origin and identified through the 'histone code'.
On the Background Stratospheric Aerosol Layer

Abstract Balloonborne aerosol particle counter measurements are used in studying the stratospheric sulfate layer at Laramie, Wyoming, during 1978 and 1979, a 2-year volcanically quiescent period in which the layer appears to have been in a near equilibrium background state. Subtracting the background aerosol concentration from data obtained during an earlier volcanically active period indicates that the actual decay rate of volcanic aerosol is over 30% faster than one would obtain without this correction. At background, the aerosol size distribution is found to remain remarkably constant between the tropopause and an altitude of ∼25 km, with a sudden transition to a distribution dominated by smaller particles above this altitude. The observations, in some respects, compare favorably with equilibrium one-dimensional stratospheric aerosol models and thus to some extent support the concept of relatively inert tropospheric sulfurous gases, such as carbonyl sulfide and carbon disulfide as the main background s...
The Effect of Online Collaboration on Adolescent Sense of Community in Eighth-Grade Physical Science

Using a quasi-experimental, nonequivalent pretest/posttest control group design, the researchers examined the effects of online collaborative learning on eighth-grade student’s sense of community in a physical science class. For a 9-week period, students in the control group participated in collaborative activities in a face-to-face learning environment, whereas students in the experimental group participated in online collaborative activities using the Edmodo educational platform in a hybrid learning environment. Students completed the Classroom Community Scale survey as a pretest and posttest. Results indicated that the students who participated in the face-to-face classroom had higher overall sense of community and learning community than students who participated in collaborative activities in the online environment. Results and implications are discussed and suggestions for future research are provided.
An ethical defense of regulatory forbearance

Forbearance is one of the principal tools of regulatory enforcement. To regulatory critics, forbearance is reflective of venal, lazy, or weak regulators more interested in pursuing private gains than the public interest. To enforcement officials, however, such views reflect unrealistic images of regulated firms and the regulatory environment. Rather, they see forbearance as a rational and ethical response to the complexities of economic and social regulation. The ethical justification for forbearance is rooted in utilitarian moral philosophy, in which forbearance is seen as the most effective way to promote the social purposes of regulation. Nonetheless, individual acts of forbearance may fail to fulfill utilitarian ethical standards. This occurs when forbearance becomes a routinized application of organizational or extra-organizational norms, instead of a case-by-case strategy of regulatory enforcement.
Distinctive plant symptoms caused by deficiency of any one of the chemical elements essential for normal development

The effect of deficiencies of any of the-essential chemical elements on plant growth and development has recently aroused considerable interest, due to the fact that it offers a direct and logical approach to a problem which has so many practical and theoretical applications. The attempt in this paper will be to cite those references which, from the writer's point of view, have contributed something to our knowledge concerning distinctive symptoms on plants due to a deficiency of any one of the chemical elements essential for growth and development of green plants, including boron, calcium, copper, iron, manganese, magnesium, nitrogen, phosphorus, potassium, sulphur and zinc. It is not intended in the present review to attempt to cite all references concerning the nutrition and fertilization of plants, for such a bibliography would be too voluminous an undertaking. It has been pointed out by Brenchley (13) that the French school long ago called attention to the importance of certain elements required by plants in small amounts. The French school, represented by Gris (44, 45), reported in 1844 and 1847 possibly the first distinctive deficiency symptom on plants. Iron chlorosis, which was studied at this early date, was for a long time the only type of chlorosis recognized as due to shortage of a plant food element. The term chlorosis has been used so frequently in connection with iron deficiency that the two have been treated often as synonymous terms. The first attempt to make a comparison of effects on plant growth due to a deficiency of each of the earlier recognized essential elements was that published in 1849 and 1851 by Salm-Horstmar (109, 110). He used the oat plant in his studies and presented a summarized table listing the specific growth manifestations resulting when the plant was grown under conditions where each of the essential elements under study was withheld.
Single and double ionization and strong-field stabilization of a two-electron system

We calculate fully correlated time-dependent two-electron wave functions for a one-dimensional analog of ${\mathrm{H}}^{\mathrm{\ensuremath{-}}}$ exposed to a short strong-field laser pulse. The onset of two-electron stabilization is identified with an inactive core electron at intensities around ${10}^{13}$ W/${\mathrm{cm}}^{2}$ for moderate-frequency (2 eV) laser light. Conventional one-electron stabilization is found at much higher intensities and frequencies.
Library Instruction, Intervention and Immersion: A 5-Year Study of Religion and the Arts

A religion faculty member approached the author after he gave a presentation to the faculty at Waldorf College on integrated library instruction. She expressed disappointment at her students’ scholarly performance on a major research paper she assigns every semester. The ensuing discussion resulted in a campus collaboration among the author, the faculty member, the campus writing center, and the academic achievement center. This article reports on the results of a five-year study on intervention and immersion of library instruction for the class Religion and the Arts at a small liberal arts college.
Modifying Stokes' function to reduce the error of geoid undulation computations

Errors in computations of the geoid undulation, which determines the position of the geoid with respect to a reference ellipsoid, introduced by various modifications of the Stokes' function in the Stokes integral formula for the undulation are examined in light of currently available harmonic coefficients. The variants considered include the conventional Molodenskii truncation theory, in which integration is limited to a spherical cap, and the variations suggested by Molodenskii (1958) and Meissl (1971). In computations of the undulation from gravity anomalies in a spherical cap and terrestrial and satellite harmonic potential coefficients (GEM 9 and GEM 10B), it is shown that either of the modifications to the conventional Molodenskii theory results in substantial reductions in truncation errors, with the simpler modification of Meissl even providing superior results in certain circumstances.
A finite representation for a superstring scattering amplitude and its low-energy limit

The divergence of the one-loop graviton-graviton scattering amplitude in the type-II superstring theory is resolved by separating the amplitude into terms corresponding to different orders of inserting the graviton vertex operators. Each term is well defined in an appropriate kinematic region and can be analytically continued to physical regions where it develops branch cuts required by unitarity. The scalar factor for each term contains the proper-time representation of a box diagram with internal lines summed over the mass levels of the superstring. There are additional terms polynomial in the external momenta. String theory gives the diagrams an intrinsic ultraviolet cut-off, and the low-energy field theory limit appears when only massless internal states are kept. One-particle reducible graphs are generated from duality by summing over an infinite set of mass levels on an internal line.
Machiavelli’s Soderini and the problem of necessity

Abstract Drawing principally on a particular example discussed by Machiavelli, this article seeks to clarify the concept of necessity and assess the Machiavellian contentions that evil-doing is in politics often necessary and justified. The example indicates that claims of necessity are best construed as allegations that evil-doing is “indispensable.” The example also indicates that these allegations are often suspect because these typically reflect limited information and knowledge and often biases and rationalizations as well, although this is not stressed by Machiavelli. Instead, Machiavelli stresses the dangers and difficulties statesmen often confront when seeking to secure important political ends or avoid costly failures, dangers and difficulties which he believes are ultimately related to the nature of human beings and the character of political elites. With respect to the morality of evil-doing, Machiavelli is suggestive of different kinds and forms of justification. Five kinds are described, and all are found unsatisfactory.
Lymphadenectomy for Adenocarcinoma of the Gastroesophageal Junction (GEJ): Impact of Adequate Staging on Outcome

Introduction Adequate staging of gastric cancer requires examination of at least 15 lymph nodes. Most resected patients are inadequately staged potentially confounding the interpretation of clinical data. The aim of this study was to determine whether adequate staging revealed different prognostic factors or improved survival compared with patients with <15 nodes examined after R0 resection for GEJ cancer.
Procainamide-induced pericardial effusion

Abstract A case of hemodynamically significant pericardial effusion due to a procainamide-induced SLE-like syndrome is reported. This case emphasizes that the acute pleuropericardial syndrome seen after procainamide therapy is potentially dangerous. Close follow-up of patients taking procainamide is warranted.
EOT, Workfunction, and Vfb Roll-Off in HfO2/Metal Gate Stacks

At a given thickness of HfO 2 , atomic layer deposited (ALD) TaN metal-gates showed higher equivalent oxide thickness (EOT) and flat-band-voltage (V fb ) shift compared to physical vapor deposited (PVD) TaSiN after annealing at 750degC for 30 min in N 2 . TEM data revealed the growth of a thicker interfacial oxide of 1.7 nm for TaN compared to 0.9 nm for TaSiN. In addition, TaN showed higher effective workfunction of 4.7 eV compared to 4.4 eV for TaSiN. However, both TaN and TaSiN exhibited V fb roll-off when the HfO 2 thickness was decreased below 4 nm. XPS measurements showed the presence of 6 atom% oxygen in TaN, whereas no significant amount of oxygen was detected in TaSiN. Electrical results are discussed in terms of the oxygen content in metal-gates and oxygen vacancy in HfO 2 .
John J. Crittenden defends a “scoundrel”

(1961). John J. Crittenden defends a “scoundrel”. The Southern Speech Journal: Vol. 27, No. 1, pp. 7-19.
Myelodysplastic features in visceral leishmaniasis.

We have detected trilineage myelodysplasia in two children recently diagnosed to have visceral leishmaniasis (V.L.), which led us to investigate retrospectively available peripheral blood and bone marrow aspirate smears of 5 children previously diagnosed as V.L. We saw that they also had trilineage myelodysplasia. We postulate that elevated levels of tumor necrosis factor-alpha (TNFalpha) may cause trilineage myelodysplasia in the patients with V.L. This nonclonal myelodysplasia may be responsible for pancytopenia along with hypersplenism, hemolysis and reticuloendothelial hyperplasia causing abnormal retention of iron in V.L.
Movements of pacific bluefin tuna (Thunnus orientalis) in the Eastern North Pacific revealed with archival tags

In this study, 253 Pacific bluefin tuna were archivally tagged off the coast of California, USA and Baja California, Mexico between August 2002 and August 2005. One hundred and fifty-seven fish were recaptured and 143 datasets were obtained and analyzed, yielding electronic tag datasets of up to 1203 days. Mean days at large for the 143 fish was 359 ± 248 (SD) days. A total of 38,012 geolocations were calculated from light-based longitude and SST-based latitude estimates, allowing us to examine the seasonal movement of juvenile bluefin tuna off the west coast of North America. Electronic tagged bluefin tuna showed repeatable seasonal movements along the west coast of North America. Bluefin tuna were found farthest south in the spring when they were located off southern Baja California, Mexico and farthest north in the fall when fish were found predominately off central and northern California. Fish showed latitudinal movement patterns that were correlated with peaks in coastal upwelling-induced primary productivity. Interannual variation in the locality of these productivity peaks was linked with a corresponding movement in the distribution of tagged fish. Overall geographical area occupied by tagged bluefin varied with primary productivity, with fish being more tightly clustered in areas of high productivity and more dispersed in regions of low productivity. In the spring through fall, bluefin tuna were located in areas with the highest levels of primary productivity available in the California Current ecosystem. However, in the winter months, tagged bluefin tuna were found in areas with lower productivity compared to other regions along the coast at that time of year suggesting that during the winter, bluefin tuna are feeding on aggregations of pelagic red crabs, sardines and anchovies that preferentially spawn in areas of reduced coastal upwelling.
Pressure effects on the phase behavior of a propylene/water/surfactant mixture

The phase behavior of the propylene/water/Tergitol 7 surfactant ternary mixture has been examined as a function of pressure at 25.5C. Unlike conventional liquid alkane based systems, a three-phase region is obtained in the absence of added electrolyte. This is likely due to a higher upper critical solution temperature for the propylene/Tergitol 7 binary mixture, in comparison to that for mixtures of various anionic surfactants and liquid alkanes. The effect of increasing pressure is similar to the effect of decreasing temperature or increasing electrolyte concentration, according to the Kahlweit phenomenological model for amphiphile/water/oil phase behavior (as well as models describing effects on interfacial curvature, such as the R ratio). The conductivities of the nominally propylene-continuous upper phases in the systems examined are high enough to suggest electrical percolation, implying the presence of significant volume fractions of micelles in these phases.