cssi/SciSciGPT-SciSciNet huggingface dataset:
Polyphosphate Storage and Function in Acidocalcisomes

Bacterial and eukaryotic polyphosphate (polyP) accumulates in acidic vacuoles that have been named the acidocalcisomes to highlight their high calcium content together with the presence of other inorganic and organic cations. The large amount of polyP and cations in acidocalcisomes explains their high electron density when they are examined by electron microscopy. PolyP synthesis and translocation to the yeast acidocalcisome-like vacuole is catalyzed by the vacuolar transporter chaperone 4 (Vtc4), which is the catalytic subunit of the VTC complex and requires a proton gradient generated by the proton pump for this translocation. Similar VTC complexes have been found in acidocalcisomes of trypanosomatids and algae. Acidocalcisome polyP could be rapidly hydrolyzed under alkaline or hyposmotic stress. Hydrolysis of acidocalcisome polyP has been studied in trypanosomatids where it is catalyzed by an exopolyphosphatase (PPX) or by the exopolyphosphatase activity of a vacuolar soluble pyrophosphatase (VSP). It has been found that this hydrolytic process favors the release of osmolytes (phosphorus and cations) to the cytosol helping the regulatory volume decrease that follows hyposmotic stress. In some mammalian cells, like platelets and mast cells, acidocalcisome polyP is released into the circulation where it can have potent procoagulant, antifibrinolytic, and inflammatory actions and, under pathological conditions, could be involved in thrombosis. Fusion of acidocalcisomes with the contractile vacuole complex of Chlamydomonas reinhardtii, Dictyostelium discoideum, and Trypanosoma cruzi could also be involved in transfer of polyP or its hydrolytic products to the bladder to increase its osmolarity and ensuing water uptake necessary for its function. Finally, downregulation and upregulation of the expression of enzymes involved in polyP metabolism have revealed the role of polyP in growth, infectivity, and persistence of different parasites.
Raft-Like Domains are Driven Together by Pufa

Fish oils rich in omega-3 polyunsaturated fatty acids (n-3 PUFAs), such as docosahexaenoic acid (DHA, 22:6), have a wide variety of health benefits but a complete molecular mechanism is yet to be elucidated. One model postulates that n-3 PUFAs are incorporated into the plasma membrane and reorganize lipid rafts. To investigate this model, we compared lipid bilayers composed of PDPC (1-palmitoyl-2-docosahexaenoylphosphatidylcholine) or POPC (1-palmitoyl-2-oleoylphosphatidylcholine) in mixtures with raft-forming, SM (sphingomyelin) and cholesterol (1:1:1 mol). A combination of solid state 2H NMR, confocal imaging and coarse grain MD simulations were employed. In the PDPC mixture, individual NMR signals assigned to deuterated analogs of each lipid in ordered raft-like domains and disordered non-raft domains were resolved in the spectra recorded for aqueous multilamellar dispersions. In the POPC mixture, by contrast, separate signals were not resolved. Our interpretation is that PDPC promotes the formation of larger domains between which the diffusion-mediated exchange of lipids is slow, whereas the domains are smaller with POPC and the exchange of lipids between them is fast. This interpretation is supported by imaging studies of GUV (giant unilamellar vesicles) and MD simulations. Controlling the size of lipid rafts may be, we propose, an underlying role for PUFA in the plasma membrane.
Individual Differences in Cognitive Function in Older Adults Predicted by Neuronal Selectivity at Corresponding Brain Regions

Relating individual differences in cognitive abilities to neural substrates in older adults is of significant scientific and clinical interest, but remains a major challenge. Previous functional magnetic resonance imaging (fMRI) studies of cognitive aging have mainly focused on the amplitude of fMRI response, which does not measure neuronal selectivity and has led to some conflicting findings. Here, using local regional heterogeneity analysis, or Hcorr, a novel fMRI analysis technique developed to probe the sparseness of neuronal activations as an indirect measure of neuronal selectivity, we found that individual differences in two different cognitive functions, episodic memory and letter verbal fluency, are selectively related to Hcorr-estimated neuronal selectivity at their corresponding brain regions (hippocampus and visual-word form area, respectively). This suggests a direct relationship between cognitive function and neuronal selectivity at the corresponding brain regions in healthy older adults, which in turn suggests that age-related neural dedifferentiation might contribute to rather than compensate for cognitive decline in healthy older adults. Additionally, the capability to estimate neuronal selectivity across brain regions with a single data set and link them to cognitive performance suggests that, compared to fMRI-adaptation—the established fMRI technique to assess neuronal selectivity, Hcorr might be a better alternative in studying normal aging and neurodegenerative diseases, both of which are associated with widespread changes across the brain.
Government Regulation of Nanotechnology: Imperfectly Essential

Just as this study of public groups revealed sometimes nuanced perceptions and valuations of the risks and benefits of nanotechnologies, it also uncovered a complicated network of attitudes about regulation. This chapter reports on the study’s findings of public groups’ attitudes about regulating nanotechnology, including perceptions of different kinds of regulatory bodies and industry self-regulation. Based on close examination of the statements and reactions in these public groups, we found ambivalence within most public groups about a wide variety of regulatory schemes, but a widespread and strong support for mandatory labeling of nanoscale ingredients and engineered nanoparticles in consumer products.
Assessing Risk at Low Doses

Although a risk assessment based on extrapolation of risk from high-dose studies to the low-dose region gives the appearance of a relatively precise estimate of low-dose risk, in fact knowledge is required about the biological mechanisms involved before one can derive an appropriate extrapolation model.
Osimertinib as First-Line Treatment in EGFR-Mutated Non–Small-Cell Lung Cancer

Genetic analysis is now routine in metastatic non–small-cell lung cancer (NSCLC) to identify somatic sensitizing mutations in EGFR, typically L858R and exon 19 deletion (Ex19del). Patients with the...
Multimodal hard x-ray imaging with resolution approaching 10 nm for studies in material science

We report multimodal scanning hard x-ray imaging with spatial resolution approaching 10 nm and its application to contemporary studies in the field of material science. The high spatial resolution is achieved by focusing hard x-rays with two crossed multilayer Laue lenses and raster-scanning a sample with respect to the nanofocusing optics. Various techniques are used to characterize and verify the achieved focus size and imaging resolution. The multimodal imaging is realized by utilizing simultaneously absorption-, phase-, and fluorescence-contrast mechanisms. The combination of high spatial resolution and multimodal imaging enables a comprehensive study of a sample on a very fine length scale. In this work, the unique multimodal imaging capability was used to investigate a mixed ionic-electronic conducting ceramic-based membrane material employed in solid oxide fuel cells and membrane separations (compound of Ce0.8Gd0.2O2−x and CoFe2O4) which revealed the existence of an emergent material phase and quantified the chemical complexity at the nanoscale.
Capping and freeze-fracture analysis of Sezary cells

The functional integrity of blood and skin Sezary cells was examined in regard to motility, capping proficiency, and intramembranous particle (IMP) mobility. In contrast with chronic lymphocytic leukemia lymphocytes, which are relatively inert in these respects, variable proportions of Sezary cells are motile and are able to cap and cluster their IMP's. Since these functions may reflect a cell's propensity for diapedesis, these observations may help to explain the inverse relationship between the size of the skin infiltrate and the number of circulating Sezary cells often observed in this condition.
Cherry-Picking as a Robustness Tool

When there are problems with data quality, it often happens that a reasonably large fraction is good data, and expresses a clear statistical signal, while a smaller fraction is bad data that shows little signal. If it were possible to identify the subset of the data that collectively expresses a strong signal, then one would have a robust tool for uncovering structure in problematic datasets. This paper describes a search strategy for finding large subsets of data with strong signals. The methodology is illustrated for problems in regression. This work is part of a year-long program in statistical data mining that has been organized by SAMSI, the new National Science Foundation center for research at the interface of statistics and applied mathematics.
The power of brainpairing: Dyads balance performance and enjoyment goals in brainstorming groups

Four studies investigate the beliefs that drive people’s preference for brainstorming in interactive groups. Study 1 revealed that the beliefs that groups are more productive, creative, and enjoyab...
Integrating Retention Rates into Economic Analyses of Prevention Interventions

Evidence-based prevention interventions hold great promise for enhancing the well-being of individuals, families, and society. As these interventions are implemented in new contexts and at wider scales, policymakers and private sector organizations are increasingly interested in understanding the economic returns that programs produce through reductions of burden on public service systems, such as criminal justice and human services. Thus, it is important to ensure that economic models account for factors, such as retention, which are important when interventions are implemented in real-world contexts with selective populations and voluntary participation. Yet the field of prevention has provided little guidance to help researchers and policymakers analyze the economics of interventions so that estimates reflect the impact of implementation factors on intervention cost-effectiveness. This paper discusses the role retention plays in the economic efficiency of interventions when the prevention of child maltreatment is the primary motivation for funding these programs. We present a conceptual model to serve as a guide for explicit inclusion of retention rates when calculating cost estimates to be used in cost-effectiveness analysis. A case study is presented, demonstrating the variability in estimates dependent on the definition of retention and the estimated retention rate. The results underscore the importance of improving our understanding of factors underlying and related to retention, such as engagement, which may improve the precision of cost and cost-effectiveness analysis in applied settings.
Efficient Associative Search in Brain-Inspired Hyperdimensional Computing

Editor’s note: This article describes a method for efficient hypervector operations using a grouping strategy for reduced computations. Quantization is used for reducing the number of multiplications, whereas caching of magnitude is used for eliminating redundant computations. — Shao-Wen Yang, Intel Corporation
Treatment-Induced Neuropathy of Diabetes (TIND) in Pediatrics: A Case Report and Review of the Literature

Context Treatment-induced neuropathy of diabetes (TIND) is a rarely reported but important consideration in patients presenting with an acute onset of neuropathic symptoms following rapid correction of hyperglycemia in diabetes. Although it has been reported in children, the preponderance of literature focuses on adults with TIND. Case description We report an 18-year-old male with this condition and his clinical course. We then discuss the proposed pathophysiology of TIND and review the literature. We also provide a standard workup for the diagnosis of TIND. Conclusion In both pediatric and adult populations, TIND should be considered in diabetic patients who develop neuropathy acutely following rapid correction of hyperglycemia. Because the pathophysiology of TIND remains poorly understood, there is insufficient information regarding how to target susceptible individuals and prevent the development of TIND.
The correlation of father involvement with social adaptation of preschool children

Objective To investigate the correlation of father involvement with early social adaptation behaviors.Methods With social adaptation scale for infant-junior middle school' s student and a self-made questionnaire,1246 normal children,age from 16 to 72 months,were investigated.Regression analysis was performed to get the correlation of social adaptation with time and activities of father involved.Results After controlling for mother-,child- and family-related factors,the regression analysis showed that standard score of social adaptation was positively rehted with the time of father involved ( β =0.05,P=0.03 ),the time father invloved explain 12％of the variation of social adaptation.The father-child activities were related with social adaptation behavior,playing was related with work skills (β =0.09,P＜0.01 ) and socialization ( β =0.06,P＜0.05),story listening related with communication ( β =0.07,P ＜ 0.05) and self-management ( β =0.06,P ＜ 0.05 ),other activities related with self-dependence ( β =0.07,P＜0.05) and work skills ( β =0.06,P＜0.05).Conclusion The time and activities of father involved are related with children' s social adaptation.The effect of father involvement on early social adaptation is positive. Key words: Social adaptation; Pre-sehool children; Father involvement
A simple Ca2+-imaging approach to neural network analysis in cultured neurons

Abstract Ca2+-imaging is a powerful tool to measure neuronal dynamics and network activity. To monitor network-level changes in cultured neurons, neuronal activity is often evoked by electrical or optogenetic stimulation and assessed using multi-electrode arrays or sophisticated imaging. Although such approaches allow detailed network analyses, multi-electrode arrays lack single-cell precision, whereas optical physiology requires advanced instrumentation. Here we developed a simple, stimulation-free protocol with associated Matlab algorithms that enables scalable analyses of spontaneous network activity in cultured human and mouse neurons. The approach allows analysis of overall networks and single-neuron dynamics, and is amenable to scale-up for screening purposes. We validated the new method by assessing human neurons with a heterozygous conditional deletion of Munc18-1, and mouse neurons with homozygous conditional deletions of neurexins. The approach described here enabled identification of differential changes in the amplitudes and synchronicity of neuronal spikes during network activity in these mutant neurons, demonstrating the utility of the approach. Compared with current imaging platforms, our method is simple, scalable, accessible, and easy to implement. It enables quantification of more detailed parameters than multi-electrode arrays, but does not have the resolution and depth of more sophisticated yet labour-intensive analysis methods, such as patch-clamp electrophysiology. The method reported here is scalable for a rapid direct assessment of neuronal function in culture, and can be applied to both human and mouse neurons. Thus, the method can serve as a basis for phenotypical analysis of mutations and for drug discovery efforts.
Motion-Dependent Effects of Functional Magnetic Resonance Imaging Preprocessing Methodology on Global Functional Connectivity.

Background: While functional magnetic resonance imaging (fMRI) has become an established noninvasive tool for studying brain activity in both healthy and diseased states, no broad consensus has bee...
Learning from Family Mysteries: Accounting for Untold Stories in Family Memory Practices

Given the importance and social significance of passing down family stories to each generation, why do important family stories not get told? How should designers of digital family storytelling platforms address missing or incomplete parts of narratives? Drawing from the results of an interview-based, practice-oriented inquiry, we argue that non-telling should be considered an important and integral part of family storytelling. Our findings show that non-telling is not simply silence. Non-telling allows family members to observe protective and discretionary values essential to the identity-making and relational goals of family storytelling. We also show ways that a person's reticence is situated and may change over time. In our discussion, we provide design strategies for family storytelling technologies to make room for silence and incorporate the values, purposes, and practices of non-telling.
Vaginal Laceration in an Open Pelvic Fracture Case Report: A Novel, Prophylactic Antibiotic Delivery Mechanism.

Introduction Rotational displaced pelvic ring injuries are associated with internal injuries to both the gastrointestinal and genitourinary viscera and anatomic structures. Vaginal lacerations and open genitourinary-associated injuries are at increased risk of mortality due to sepsis. Case Presentation. This case presents a 65-year-old female status post-pedestrian-vehicle struck diagnosed with an open pelvic fracture with extension into the outer one-third of the vaginal wall. The patient was successfully treated with emergent surgical debridement, pelvic stabilization, and internal placement of a novel combination of metronidazole antibiotic gel and vancomycin/tobramycin Polymethyl methacrylate beads. Conclusion No evidence of infection was observed with the use of topical metronidazole-coated vancomycin/tobramycin Polymethyl methacrylate beads for contaminated open pelvic fracture injury involving the vaginal wall. Further research on antibiotic gels for use in high-risk open fractures is required.
Hemodynamic alternations following stent deployment and post-dilation in a heavily calcified coronary artery: In silico and ex-vivo approaches.

Abstract In this work, hemodynamic alterations in a patient-specific, heavily calcified coronary artery following stent deployment and post-dilations are quantified using in silico and ex-vivo approaches. Three-dimensional artery models were reconstructed from OCT images. Stent deployment and post-dilation with various inflation pressures were performed through both the finite element method (FEM) and ex vivo experiments. Results from FEM agreed very well with the ex-vivo measurements, interms of lumen areas, stent underexpansion, and strut malapposition. In addition, computational fluid dynamics (CFD) simulations were performed to delineate the hemodynamic alterations after stent deployment and post-dilations. A pressure time history at the inlet and a lumped parameter model (LPM) at the outlet were adopted to mimic the aortic pressure and the distal arterial tree, respectively. The pressure drop across the lesion, pertaining to the clinical measure of instantaneous wave-free flow ratio (iFR), was investigated. Results have shown that post-dilations are necessary for the lumen gain as well as the hemodynamic restoration towards hemostasis. Malapposed struts induced much higher shear rate, flow disturbances and lower time-averaged wall shear stress (TAWSS) around struts. Post-dilations mitigated the strut malapposition, and thus the shear rate. Moreover, stenting induced larger area of low TAWSS ( 2000 s−1), indicating higher risks of in-stent restenosis (ISR) and stent thrombosis (ST), respectively. Oscillatory shear index (OSI) and relative residence time (RRT) indicated the wall regions more prone to ISR are located near the malapposed stent struts.
The Impact of Research and Development on Economic Growth and Productivity in the U.S. States: Online Appendix

This online appendix accompanies the article forthcoming in the Southern Economic Journal. This appendix contains additional information on the data and methodology used in the article, as well as results from additional and supplementary estimations.
Epidemiology and Prevalence of Abnormal Results for Anal Cytology Screening in HIV-Infected Young Men Who Have Sex with Men.

Abstract Purpose: To determine the prevalence and risk factors for dysplasia in an urban population of HIV-infected young men who have sex with men (YMSM) and to determine the adherence to guidelines for anal cytology screening. Methods: The electronic medical record was utilized to collect pre-existing demographic information, medical history, laboratory data, and anal cytology results. Results: Among 60 subjects (mean age 21.2 years) at their first diagnostic anal cytology, 32 (53.3%) had an anal cytological abnormality and 28 (46.7%) had normal anal cytology. The abnormal results were as follows: 21 (65.6%) had atypical squamous cells of undetermined significance (ASCUS), one (3.1%) had atypical squamous cells and high-grade squamous intraepithelial lesion could not be excluded, nine (28.1%) had low-grade squamous intraepithelial lesion, and one (3.1%) had high-grade squamous intraepithelial lesion. In univariate analysis, abnormal anal cytology was not associated with any of the identified risk factor...
Single-wavelength 108 Gb/s upstream OFDMA-PON transmission

We experimentally demonstrate 108-Gb/s/λ upstream OFDMA-PON transmission over 20km SSMF and a 1∶32 split, enabled by ONU carrier suppression and OLT heterodyne coherent reception. This is the highest-rate single-wavelength upstream PON transmission to date.
Methylation Markers for Early Detection and Differentiation of Follicular Thyroid Cancer Subtypes

Thyroid cancer has the fastest rising incidence rates and is the fifth most common cancer in women. There are four main types of which the papillary and follicular types together account for >90%, followed by medullary cancers (3%-5%) and anaplastic carcinomas (<3%). For individuals who present with early stage disease of papillary and follicular cancers, there are no accurate markers to predict whether they will develop metastatic or recurrent disease. Our immediate goal is to molecularly differentiate follicular cancer subtypes for enhanced classification. Promoter methylation status of genes with reported associations in thyroid cancer (CASP8, CDKN2A, DAPK1, ESR1, NIS, RASSF1 and TIMP3) were examined in a cohort of follicular thyroid cancers comprising of 26 Hurthle and 27 Classic subtypes utilizing quantitative methylation-specific PCR. RASSF1 was differentially methylated in Classic tumor tissue compared to Hurthle (p<0.001). Methylation of RASSF1 pointed to racial group differences between African Americans and Caucasian Americans (p=0.05). Extra thyroidal extension was found to be associated with DAPK1 (p=0.014) and ESR1 (p=0.036) methylation. Late stage disease was associated with older age (p<0.001) and methylation of DAPK1 (p=0.034) and ESR1 (p=0.035). The methylation status of RASSF1, DAPK1 and ESR1 suggests the utility of methylation markers to molecularly differentiate thyroid cancer subtypes for enhanced classification and early detection of thyroid cancer.
An evaluation of a foundations of physical activity course.

Abstract The purpose of this study was to determine the effectiveness of the Foundations of Physical Activity course at the University of Oregon in the areas of (a) attitude toward physical activity, (b) voluntary physical activity behavior, (c) self-assessment ability on selected physical fitness performances, and (d) knowledge of the principles and benefits of physical activity. Pre-and-post questionnaires and tests were administered to control (N = 64) and experimental (N = 64) groups on attitude, physical activity behavior, and knowledge. Pre-and-post questionnaires and tests on self-assessment were administered to the experimental group. Results showed that attitude toward physical activity of the experimental group dropped significantly and that although voluntary physical activity of both the experimental and control groups dropped significantly, there was no significant difference between the two groups. Subjects were significantly better able to assess themselves on selected fitness performances ...
Model validation in l/sub 1/ using frequency-domain data

In this paper we study the problem of invalidating uncertain models with an additive uncertainty. The problem is to check the existence of an uncertainty and a measurement noise which fit to the given model structure and the uncertainty/noise description, as well as the experimental data used for invalidation. We consider a mixed setting in which the uncertainty is characterized in time domain by the l/sub 1/ induced system norm, while the available data are frequency response samples of the system. We show that this problem, which by formulation poses an infinite-dimensional primal optimization problem, can be solved in a dual, finite-dimensional space with finitely many constraints.
Leadership, loss, and healing: A study of women community college leaders who left the presidency

The purpose of this qualitative study was to extend research on female community college presidents by (a) describing and examining the experiences of women who have experienced difficult leadership positions that resulted in departures from community college presidencies; and (b) exploring how these women have made meaning from this experience. Three female community college presidents who had experienced a difficult leadership experience that resulted in leaving the presidency were interviewed to learn about how they viewed their leadership experiences, described what they had learned about leadership, explained about presidential relationships with governing boards, and constructed meaning as a result of leaving a presidency. Using a constructivist framework and feminist methodology, the study data were first analyzed for each president and presented as an individual case study. Next the data were reanalyzed collectively to make interpretations about the shared experiences of all three presidents. The results of the study resulted in six themes. Leadership: (a) transformationalfeminist leadership; Loss: (b) challenging situations with board members, (c) dealing with power struggles, (d) commitment to the college; and Healing: (e) spirituality and reflection, (f) continually creating meaning. In addition to describing six troublesome situations that presidents can face when dealing with governing boards and individual board members, the president’s career-long leadership experiences, including some difficulties, suggested a style of leadership adapted from existing transformational and feminist leadership approaches. The Transformational-Feminist, with qualifiers, Leadership Model combines the two approaches and proposes limitations to the model’s elements suggested by the emergent understanding that resulted from studying leaders who had difficult experiences.
Record of seafloor CaCO3 dissolution in the central equatorial Pacific

[1] Shell weights for Globigerina sacculifer, Pulleniatina obliquiloculata, and Neogloboquadrina dutertrei from cores raised from a depth of 4.36 km (at 2°S, 140°W) reveal large dissolution-related shifts at Termination I and at the marine isotope stage 5-4 boundary. These shifts suggest that the carbonate ion concentration at this depth was ∼27 μmol kg−1 higher during glacial time than during marine isotope stages 1 and 5 and that the boundaries separating these regimes were quite sharp (in other words, the dissolution chronology has a rectangular character). However, when compared to results for a much shallower core, there are disconcerting aspects to this data set. One is that the initial shell wall thickness may depend on growth conditions. Hence the estimates of paleocarbonate ion concentrations presented here remain tentative.
Continuity of Medical Care and Risk of Incarceration in HIV-Positive and High-Risk HIV-Negative Women

Objectives: Incarceration rates in the United States have tripled over the past two decades and have increased even more rapidly among women than men. To identify risk factors that predict incarceration in HIV-positive (HIV+) and high-risk HIV-negative (HIV-) women and to evaluate the association between continuity of medical care and risk of incarceration, this analysis was conducted. Methods: This was a prospective cohort study of HIV+ and high-risk HIV- women enrolled between April 1993 and January 1995 at four urban centers: Providence, Rhode Island; New York, New York; Baltimore, Maryland; and Detroit, Michigan. The HIV Epidemiology Research (HER) Study enrolled 871 HIV+ and 439 high-risk HIV- innercity women between the ages of 16 and 55 years. All participants had a history of injection drug use or high-risk sexual behavior. Interviews, including questions on continuity of medical care and incarceration, were administered at baseline and 6 and 12 months after enrollment. Any incarceration in the 1-...
Polarographic reduction of aldehydes and ketones: Part XXX. Effects of acid-base, hydration-dehydration and keto-enol equilibria on reduction of α-ketoglutaric and oxalacetic acid and their esters

Abstract Oxalacetic acid is reduced in four waves, corresponding to the reduction of the following species: i1a, keto form of the acid; i1b, enol form of the acid; i2, monoanion; i3, dianion. Reduction of the acid and monoanion occurs after protonation of the CO group, that of the dianion on the unprotonated CO group. Ethyl oxalacetate is reduced in corresponding waves i1a, i1b and i2, the free ester after protonation of the CO group, the monoanion without. Diethyl oxalate is also reduced in the keto (i1a) and enol (i1b) form after pre-protonation, but also in the unprotonated form in wave i2. α-Ketoglutaric acid is reduced in three waves, i1 (acid), i2 (monoanion) and i3 (dianion), the first two with pre-protonation of the CO group, the third without. Diethyl α-ketoglutarate is reduced in the accessible pH-range in a single two-electron wave, where the CO group is reduced after pre-protonation. Carbanion-enolates are not reducible. Using the dependence of peak currents obtained by LSV on ν 1 2 values of equilibrium constants for the hydration-dehydration reaction (Kd) involving the CO group were determined. α-Ketoglutaric acid exists in aqueous solution 65%, its diethyl ester 75%, oxalacetic acid and its ethyl ester 87% and diethyl oxalacetate 93% in the hydrated form. Anions and dianions (with the exception of ethyl oxalacetate) are pratically unhydrated. Hydration and acid-base catalyzed dehydration results in pH-dependence of polarographic reduction currents. The limiting current is governed by the rate of dehydration and from the intensity of the current (in the region where it is pH-dependent) and Kd-values it is possible to calculate rate constants (kd) of the dehydration (Table 8). When compared with dehydration, keto-enol equilibria are slowly established. From the ratios of the currents, i1b: i1a, the value of KE = [enol]/[keto] has been obtained for oxalacetic acid (0.12), its monoethyl (0.47) and diethyl ester (0.42). Structural effects on reduction potentials, keto-enol equilibria and hydration are discussed.
Genetics of PNH

Publisher Summary In terms of the nosographic classification of human diseases, paroxysmal nocturnal hemoglobinuria (PNH) is rather special and perhaps unique because, although it results from somatic mutations, it is not truly a malignant disease. PNH has never been reported as a congenital disease and there is no family clustering. Thus, it is an acquired disease. As a consequence, the genetics of PNH is somewhat unconventional, relating not to inheritance but to somatic cell genetics. Formal genetic analysis has revealed in somatic cell hybrids that inactivating mutations of PIG-A are recessive, in keeping with the fact that this gene encodes one subunit of an enzyme. Biochemical genetics has identified a specific metabolic block in the glycosylphosphatidylinositol biosynthetic pathway, the transfer of GlcNAc onto phosphatidyl inositol. The molecular genetics of PIG-A has confirmed its sequence homology with a GIcNAc transferase and revealed in PNH patients a variety of mutations that cause either complete or partial loss of function of the gene product
Reduction In Genetics—Doing the Impossible

Publisher Summary This chapter discusses reduction in genetics. A biological theory, Mendelian genetics, is being reduced to a physicochemical theory, molecular genetics. Hereditary phenomena are now being explained in terms of the transmission and functioning of nucleic acids in the production of proteins rather than by means of the behavior of purely biological entities such as genes. The history of the transition from Mendelian to molecular genetics has been told often and well, but the philosophical implications of this transition have been all but ignored, perhaps because these implications appear to be too obvious. In theory reduction, the axioms of the theory being reduced are derived from those of the reducing theory with the aid of appropriate reduction functions which associate certain key terms and phrases in one theory with corresponding words and phrases in the other. However, before the necessary derivations can be shown, the two theories must be reconstructed. That is, a degree of consistency and order must be introduced into the two theories which are greater than that usually found in actual scientific theories as they exist in the changing course of science.
Tapping the Private Sector: Approaches to Managing Risk in Water and Sanitation

The study highlights the variety of risks that occur in the provision of water and sanitation services and describes in considerable detail the mechanisms used to allocate and mitigate those risks. Where risks are clearly identified and managed, the prospects of success go up. Clearly, there is no magic bullet here: even the successful projects have faced challenges. However, the experience thus far leads to an optimistic prospect for the future. A variety of experiments are ongoing in all parts of the world. Some projects have faced challenges but typically all parties have demonstrated a willingness to find solutions that improve the basis for success. Looking ahead, the interests of governments and the private sector lie in continued efforts to identify arrangements that provide cost effective and quality service while rewarding risk bearing. Pressures for moving ahead have resulted in pragmatic approaches to risk reduction and risk sharing in a variety of contexts, and the prognosis for the future is positive.
Young Adolescents' Situational Coping during Adult Intimate Partner Violence

A purposively recruited, ethnically diverse sample (N = 27) of young adolescents and their mothers in domestic violence shelters described adolescents' coping responses during adult intimate partner violence as part of a qualitative study using Life Story methods. Findings revealed competing demands and several responses, including: leaving home, collaborating with family members for safety, calling police, verbally or physically intervening, seeking help outside the family, and palliative responses. Participants provided context-rich accounts of coping and coping goals during violence, including information on help-seeking and police involvement. Implications are discussed for future research and developing interventions to improve safety and psychological outcomes.
Surgical resident involvement differentially affects patient outcomes in laparoscopic and open colectomy for malignancy.

Abstract Background We evaluated effect of resident involvement on outcomes after laparoscopic and open colon resection for malignancy. Methods Patients undergoing colectomy were queried using the American College of Surgeons' National Surgical Quality Improvement Program. "Attending alone" and "Resident" cohorts were compared with primary end point of overall morbidity. Results Of 37,330 patients, residents were involved in 26,190 (70.2%) cases. Attending alone patients were older with higher vascular, cardiac, and pulmonary comorbidity. Univariate analysis demonstrated increased operative time (181.0 ± 98.4 vs 138.7 ± 77.0, P P = .041), and readmission rates (11.9% vs 9.6%, P = .037) with resident involvement. Serious (16.0% vs 13.9%, P P P P P P P Conclusions Resident participation in colectomy for malignancy is associated with lower mortality at the expense of higher overall morbidity.
Body mass index predicts cecal insertion time: the higher, the better.

Background: It is essential to determine the factors that predict prolonged procedural time during colonoscopy. The aim of this study was to determine the effect of body mass index (BMI) on cecal insertion time (CIT) during colonsocopy. Methods: Consecutive outpatients who received colonoscopies over a 10 month period (April–October 2007) were enrolled. Exclusion criteria included colonic resection, strictures or exophytic masses precluding colonic evaluation. Data were collected for age, sex, race, height, weight, BMI, waist circumference, prior history of abdominal or pelvic surgery, history of diverticulosis, participation of fellow, CIT, quality of colon cleansing and the amount of sedation used during the procedure. Results: A total of 1430 patients (586 men and 844 women; mean age 60.3 years) were included in the final analysis. The mean CIT was 648.5 seconds (SE = 11.47). Older age, female gender, fellow involvement, poor bowel preparation and lower BMI were associated with prolonged mean CIT on linear regression analysis ( R2 = 0.116; P < 0.001). Mean CIT declined linearly with increasing BMI. Conclusion: A higher BMI is strongly associated with progressively shorter CIT.
Reactivity of hydroxyproline-rich glycoproteins and their potential as biochemical tracers of plant-derived nitrogen

The amino acid hydroxyproline (Hyp) has potential for tracing plant N because Hyp-rich glycoproteins (HRGPs), structural proteins in the cell walls of plants, are its only major biochemical source in soil. The reactivity of Hyp in tissue from three vascular plants (black mangrove leaves, smooth cordgrass and cypress needles) was investigated in a 4 yr decomposition study to test its suitability as a tracer of plant N. The reactivity was similar to that of bulk plant N in cordgrass and cypress needles, but Hyp was more resistant to decomposition in mangrove leaves. This was likely due to increased cross liking between peptides in HRGPs from dicotyledons vs. other plants. These cross links involve stable diphenyl ether and biphenyl linkages that may protect the HRGP from degradation. The results suggest that Hyp can provide a quantitative estimate of the contribution of plant residues to the detrital N pool in systems dominated by gymnosperm and monocotyledon inputs. A mixing model using litter input representative of boreal forest vegetation demonstrated the potential of Hyp for tracing plant N in soil.
The crystal structure of magnesium arsenate, Mg8.5As3O16

Abstract Single crystals of magnesium arsenate have been grown from a PbOAs2O5 eutectic by flux crystallization of a ceramic preparation having an initial composition of 6MgO·As2O5. The crystals are rhombohedral, space group R 3 m , with hexagonal unit cell parameters a = 6.0278(6) and c = 27.600(3) A. A three-dimensional structural analysis using automatic diffractometer data has been completed and refined by full-matrix least-squares procedures to a residual R = 0.049 (Rw = 0.059) with a data-parameter ratio of 36 in the final anisotropic refinement. The structure analysis indicated that magnesium arsenate has the composition Mg8.5As3O16 and is isostructural with the previously reported Co8As3O16. The structure is based upon a cubic close-packed oxygen array with charge balance achieved in magnesium arsenate through partial occupancy of a unique magnesium site occurring in an arsenic-substituted MgO-type layer.
Reservoir engineering aspects of reinjection

Abstract This paper discusses aspects of reinjection that affect geothermal reservoir performance. It is based on field observations throughout the world. Three specific areas are examined. First, the problem of maintaining reliable and consistent injectivity by avoiding precipitation of dissolved solids. Injectivity loss has been prevented in some fields, but not in all. The second problem is that of determining where the reinjected water goes, in order to analyse the likely behaviour of the system before productivity difficulties begin. In this regard tracers are the most important reservoir engineering tool, and the collective worldwide experience in their use is summarized in tables. The third problem is that of loss of production performance due to invasion of reinjected water, as has occurred in several highly fractured fields. Early recognition of this difficulty is the major purpose of tracer testing; however, the complete interpretation of these tests remains one of the most significant outstanding problems in reservoir engineering. These three aspects of the reinjection problem are discussed in detail and the current status of reservoir engineering approach to these problems is summarized. Examples are given from operating geothermal fields in Japan, New Zealand, the Philippines and El Salvador.
Characterization of High Performance Polymers Transferred by Resonant Infrared Laser Ablation

A polyamide imide and a polymeric precursor to polyimide have both been successfully transferred using resonant infrared laser ablation. Additionally a random copolymer mixture, possessing structural features common to polyimide and polyamide imide, was readily transferred using resonant infrared laser ablation. The materials are transferred with local structure intact as evidenced by Fourier transform infrared spectroscopy studies. The deposition rates of the polyimide precursor were examined at various wavelengths using a quartz crystal microbalance mounted in the deposition chamber. The effect of target type on deposition rate was also examined using two different 20 wt% polyamide imide solutions in N-methyl pyrrolidinone and dimethyl formamide and a solid pressed pellet target of polyamide imide. Both wavelength and target form were found to have a discernible effect on deposition rate. The deposited material was examined using a combination of profilometry and optical microscopy. The results show highly rough films with large, dark, string-like polymeric moieties on the surface.
Quantitative film autoradiography for tritium: methodological considerations.

Abstract The details of quantitative film autoradiography for tritium using tritium plastic standards were examined with respect to 3 issues: (1) tritium tissue equivalent (TE) calibration; (2) correction of autoabsorption differences for gray and white matter; and (3) the use of carbon-14 standard sources as a method for quantifying tritium tissue images. Both 3 H-tissue and 3 H-plastic sources produced linear log-log relationships of 3 H-concentration (nCi/mg source weight) vs source optical density (OD) over a reproducible OD range (0.080–0.800). The curves for both 3 H-tissue and 3 H-plastic were parallel; uncalibrated 3 H-plastic standards exhibited a 4-fold higher autoabsorption over 3 H-tissue sources for OD values in the linear range. Using chloroform extraction of brains from rats treated with either [ 14 H]deoxyglucose ([ 14 C]DG) or [ 3 H]deoxyglucose ([ 3 H]DG), we found neither isotope loss nor redistribution after defatting (30% reduction of tissue dry weight). After chloroform extraction, the OD values from both gray and white matter structures containing carbon-14 were unaltered. Gray matter OD values increased by 28.7 ± 5.6% (mean±S.D.) in structures containing tritium; white matter structures containing tritium exhibited a 115.9 ± 29.3% increase in OD after chloroform extraction. The increase in OD after chloroform extraction was a fixed percent for any given tritium OD value from unextracted tissue when the value was within the linear range of 0.080–0.800 OD units. The magnitude of the higher white matter autoabsorption for tritium was confirmed using tritium impregnated cow brain pastes of variable gray/white mixtures. Chloroform extraction of tissue from [ 3 H]DG treated rats was therefore a suitable procedure for direct correction of regionally heterogeneous autoabsorption of tritium. Finally, the rates of image generation for tritium and carbon-14 sources were compared. The rate of increase of OD with increasing exposure time was found to be equal for 3 H-tissue and 3 H-plastic images; sources of carbon-14 in plastic, however, exhibited more accelerated rates of image generation when compared to tritium sources (i.e. 3 H- and 14 C-images did not covary with exposure time). The effect of non-covariance on tritium TE calibrated standards was the overestimation of OD values for 14 C-plastic standards with increasing times of exposure (comparison of 4 week images to 1 week images showed errors of 35–40%). Use of carbon-14 sources to quantify tritium-generated images therefore required recalibration of 14 C-plastic for all exposure times of interest.
Storm-Water Filter Media Pollutant Retention under Aerobic versus Anaerobic Conditions

Storm-water runoff entering filters is usually aerobic and therefore the removal processes in the filter normally occur under oxidizing and aerobic conditions. However, storm-water filters differ from water and wastewater treatment filters because there are quiescent times when no influent enters the filter and the pore water stagnates. During this stagnation period, anaerobic conditions on a macro- or microscale could develop. This note presents the results of experiments conducted to determine if four potential filter media (sand, activated carbon, peat moss, and compost) could retain previously trapped pollutants when anaerobic conditions develop during interevent periods. The results indicated that permanent retention of heavy metals may occur even in an anaerobic environment (for the media and metals investigated). However, retention of some nutrients may not occur under these conditions, particularly for the organic media. This is an area of concern when the design of filters and bioretention devices includes an internal water storage zone where, between events, anaerobic conditions for nitrate removal are encouraged.
HIV-1 REVERSE TRANSCRIPTASE CAN DISCRIMINATE BETWEEN TWO CONFORMATIONALLY LOCKED CARBOCYCLIC AZT TRIPHOSPHATE ANALOGUES

It has been proposed that the preference of 3‘-azido-3‘-deoxythymidine (AZT) for the extreme 3E (south) conformation, as observed in its X-ray structure, is responsible for its potent anti-HIV acti...