cssi/SciSciGPT-SciSciNet huggingface dataset:
Epigenome-Wide Association Studies Provide Insight into the Pathogenesis of Non-alcoholic Fatty Liver Disease and Non-alcoholic Steatohepatitis

Abstract Non-alcoholic Fatty Liver Disease (NAFLD) and its progressive form or NASH with fibrosis, are rapidly increasing in conjunction with the growing rates of obesity and type II diabetes. Novel technologies such as epigenome-wide association studies (EWAS) may provide opportunities to get valuable insight into not only the mechanisms of disease, but to also discover potential biomarker targets with clinical relevance to disease stage.
Multiphysics Coupling in Lithium-Ion Batteries with Reconstructed Porous Microstructures

For an energy storage application such as electrical vehicles (EVs), lithium-ion batteries must overcome limited lifetime and performance degradation under specific conditions. Particularly, lithiu...
Teaching Feedback Skills through Letters to "Dear Obby".

How one communicates concerns about another person’s actions or performance can significantly affect both the extent to which the feedback improves behavior as well as the quality of the ongoing re...
Utilization of the p-nitrobenzyloxycarbonyl (pNZ) amine protecting group and pentafluorophenyl (Pfp) esters for the solid phase synthesis of spiroligomers

Abstract Spiroligomers are a class of peptidomimetics that connect interchangeable, stereochemically pure, cyclic monomers through pairs of amide bonds to form diketopiperazines between the monomers. This enables them to adopt predictable and programmable structure due to the rigidity of the final molecule. We present a new method for the solid phase synthesis of highly functionalized spiroligomers that incorporates the use of the p-nitrobenzyloxycarbonyl (pNZ) as a temporary amine protecting group and the pentafluorophenyl ester for monomer activation. This new method allows for the synthesis of spiroligomers with higher purity and increased yields when compared to previous methods. This improved method of synthesis of functionalized spiroligomers will facilitate the development of applications as catalysts, therapeutics and membrane channels.
Describing prairie C4 plant species area coverage using hyperspectral reflectance

ABSTRACTC3 and C4 photosynthesis pathways represent fundamental differences in vegetation characteristics and physiology. Spectral reflectance collected on the ground and from satellite successfull...
Conocimiento experto, confusión y métodos causales

espanolLa ausencia de confusion residual es la condicion fundamental para la inferencia causal a partir de datos observacionales. Incluso cuando esta condicion se cumple y los modelos estan correctamente especificados, las estimaciones de los metodos estadisticos tradicionales pueden no tener una interpretacion causal si existen confusores cambiantes que estan afectados por la exposicion. Los metodos «causales», como los modelos estructurales marginales y los modelos estructurales anidados, evitan este problema. EnglishThe absence of unmeasured confounding is the fundamental condition for causal inference from observational data. Even when this condition holds and the models are correctly specified, estimates from standard methods may not have a causal interpretation if there are time-dependent confounders that are affected by prior exposure. «Causal» methods, such as marginal structural models and structural nested models, avoid this problem.
Is Estrogen a Cellular Signal for Female Genital Tract Epithelium

In vivo, the vagina and uterus, and their respective epithelial linings, are considered to be estrogen target structures. As a result of classical endocrinological studies, their dependence on estrogen for growth and differentiation is considered axiomatic. In vitro, primary cultures of epithelial cells from the vagina and uterus, grown in collagen gel matrix in a serum-free medium, proliferate independently of the presence of added estrogen. Addition of estrogen to these primary cultures does not stimulate epithelial cell proliferation, even in suboptimal conditions, but rather retards their growth. The estrogen receptor system of these cultured cells appears to be functionally intact, and the cells respond to estrogen addition by specific product synthesis (progestin receptors). Thus, estrogen has a direct modulative effect on cultured vaginal and uterine epithelia, but estrogen is not a directly-acting mitogen for these cells. It appears that stromal and possibly organismal factors are essential synergists and/or mediators for estrogen’s well-known mitogenic effect on female genital epithelia in vivo. Several alternative pathways for estrogen action on female genital epithelia are suggested.
Lactate in trauma: a poor predictor of mortality in the setting of alcohol ingestion.

Resuscitation end point markers such as lactate and base deficit (BD) are used in trauma to identify and treat a state of compensated shock. Lactate and BD levels are also elevated by alcohol. In blunt trauma patients with positive blood alcohol levels, lactate may be a poor indicator of injury. Retrospective data were collected on 1083 blunt trauma patients with positive blood alcohol levels admitted a Level I trauma center between 2003 and 2006. Patients were stratified by Injury Severity Score, age, gender, and Glasgow Coma Score. Logistic regression analyses were used to assess lactate and BD as independent risk factors for mortality. Seventy-four per cent of patients had an abnormal lactate level compared with 28 per cent with abnormal BD levels. In patients with mild injury, lactate levels were abnormal in more than 70 per cent of patients compared with less than 20 per cent of patients with abnormal BD levels. Linear regression showed lactate is not a significant predictor of mortality. Regardless of Injury Severity Score, lactate appeared to be more often abnormal than BD in the setting of alcohol ingestion. Additionally, because BD, and not lactate, was shown to be an independent predictor of mortality, lactate may not be a reliable marker of end point resuscitation in this patient population. Language: en
Renewed Looks at the Distribution of a Sum of Independent or Dependent Discrete Random Variables and Related Problems

Butler and Stephens (2017) have investigated the exact and approximate distributions of a sum S of independent binomial random variables with different probabilities. They used a convolution approach to find the exact distribution, whereas they heavily used the moments and cumulants to find approximations. We propose two different approaches. First, we show that the moment generating function (MGF) approach is easier and simpler to implement for finding the exact distribution of S. We also provide approximations for the distribution of S using large-scale computer simulations based on one million independent replications each. Such exact and approximate distributions are very close to analogous values reported in Butler and Stephens (2017). We show versatility of our approaches by including both exact and approximate distributions for the sum S of independent multinomial, geometric and other discrete random variables.
Seeing red: diet and endometriosis risk

Endometriosis is an estrogen-dependent chronic gynecologic disorder that significantly reduces the quality of life of affected women. Characterized by adhesions of endometrial fragments in extra-uterine sites (predominantly in the peritoneal cavity and ovary but occasionally on the diaphragm, liver, and abdominal wall), the condition occurs in ~10% of the general population and is associated with infertility, pelvic pain, and increased risks for ovarian and other cancers (1,2).
Healthcare Utilization and Missed Workdays for Parents of Children With Traumatic Brain Injury.

Background We enrolled patients in a prospective study in which we obtained estimates of the direct and indirect burden for families of children with traumatic brain injury (TBI) relative to a control group of families of children with orthopedic injury (OI). Methods Parents were surveyed at 3 time points following injury: 3, 6, and 12 months. At each follow-up contact, we asked parents to list the number of workdays missed, number of miles traveled, amount of travel-related costs, and whether their child had an emergency department (ED) visit, hospital admission, any over-the-counter (OTC) medications, and any prescription medications during that time period. We assessed the difference in these outcomes between the TBI and OI groups using multivariable logistic and 2-part regression models to account for high concentrations of zero values. Results Children with TBI had significantly greater odds of having an ED visit (3.04; 95% CI, 1.12-8.24), OTC medications (1.98; 95% CI, 1.34-2.94), and prescription medications (2.34; 95% CI, 1.19-4.59) than those with OI. In addition, parents of children with TBI missed significantly more days of work (19.91 days; 95% CI, 11.64-28.17) overall during the 12 months following injury than their OI counterparts. Conclusion Extrapolating our results to the entire country, we estimate that pediatric TBI is associated with more than 670 000 lost workdays annually over the 12 months following injury, which translates into more than $150 million in lost productivity. These missed workdays and lost productivity may be prevented through safety efforts to reduce pediatric TBI.
Deep learning facilitates rapid classification of human and veterinary clinical narratives

ABSTRACT Objective Currently, dedicated tagging staff spend considerable effort assigning clinical codes to patient summaries for public health purposes, and machine-learning automated tagging is bottlenecked by availability of electronic medical records. Veterinary medical records, a largely untapped data source that could benefit both human and non-human patients, could fill the gap. Materials and Methods In this retrospective study, we trained long short-term memory (LSTM) recurrent neural networks (RNNs) on 52,722 human and 89,591 veterinary records. We established relevant baselines by training Decision Trees (DT) and Random Forests (RF) on the same data. We finally investigated the effect of merging data across clinical settings and probed model portability. Results We show that the LSTM-RNNs accurately classify veterinary/human text narratives into top-level categories with an average weighted macro F1, score of 0.735/0.675 respectively. The evaluation metric for the LSTM was 7 and 8% higher than that of the DT and RF models respectively. We generally did not find evidence of model portability albeit moderate performance increases in select categories. Discussion We see a strong positive correlation between number of training samples and classification performance, which is promising for future efforts. The use of LSTM-RNN models represents a scalable structure that could prove useful in cohort selection, which could in turn better address emerging public health concerns. Conclusion Digitization of human and veterinary health information will continue to be a reality. Our approach is a step forward for these two domains to learn from, and inform, one another.
Pharmacokinetics of monoamine oxidase B inhibitors in Parkinson's disease: current status.

ABSTRACTIntroduction: Brain function depends considerably on the neurotransmission of biogenic monoamines. Their metabolism employs monoamine oxidase-B in neuronal and glial cells. Inhibition of monoamine oxidase-B elevates biogenic amine levels. Accordingly, monoamine oxidase-B inhibitors provide a symptomatic effect via dopamine on motor symptoms in patients with Parkinson’s disease.Areas covered: This narrative review aims to describe the pharmacokinetic characteristics of the available reversible and irreversible monoamine oxidase B inhibitors for the treatment of Parkinson’s disease in daily practice. All these compounds are administered on a daily basis.Expert opinion: Reversibility or irreversibility of available monoamine oxidase-B inhibition is not relevant, due to their daily intake and half-life in clinical practice. Irreversible monoamine oxidase-B inhibitors slowed the progression of neuronal dying in experimental models of Parkinson’s disease. In patients, concomitant inhibition of monoamine...
Technology and engineering application of cross area HVDC interconnection system high-precision simulation modeling based on ADPSS

Abstract In recent years, a large number of high voltage direct current (HVDC) transmission projects have been connected to AC systems. This has started to have an impact on AC/DC hybrid power grids, particularly receiving terminal power grids. An HVDC system is a large-scale power electronic integrated nonlinear system, and it includes a primary system and a control and protection system. Hence, the precision and degree of detail of HVDC systems directly affect the actual effect of simulation. In recent years, in the case of the normal operation and failure of AC power grids, the abnormal fluctuation and even locking of HVDC systems caused by the inappropriate strategies of the control and protection system component have strongly affected power grids. This has significantly affected the safety and stability of receiving power grids and normal operation. In this study, the actual engineering HVDC control logic provided by a manufacturer is analyzed and simulated based on the user defined component library of the ADPSS electromagnetic transient calculation program, and an HVDC control model based on an actual system is established. The accuracy of the DC control custom model based on ADPSS is verified through the simulation of an actual power grid.
26. Posterior ligamentous reinforcement does not prevent proximal junctional kyphosis in adult spinal deformity

BACKGROUND CONTEXT Violation of the posterior soft tissues is believed to contribute to the development of proximal junctional kyphosis (PJK). Clinical and biomechanical studies have suggested that augmentation of the posterior ligamentous structures (PLS) may help prevent PJK. PURPOSE To determine whether augmentation of the PLS from the UIV-1 to UIV+1 prevents PJK. STUDY DESIGN/SETTING Single-surgeon retrospective cohort study. PATIENT SAMPLE One hundred fifty adult spinal deformity patients. OUTCOME MEASURES PJK (defined as a proximal junctional angle ≥20°) at final follow-up. METHODS We conducted a retrospective cohort study of 150 adult spinal deformity patients who underwent ≥5 level fusions to the pelvis by a single surgeon between 2014 and 2017. Exclusion criteria included neuromuscular or congenital scoliosis (18 patients), or follow-up less than 1 year (24 patients), leaving 108 patients available for final analysis. Patients were divided into two groups: PLS+ patients had reconstruction of the PLS between UIV+1 and UIV-1 with a surgical nylon tape while PLS- patients did not. Demographics, surgical data, and sagittal alignment parameters were compared between the cohorts. The primary outcome of interest was the development of PJK at final follow-up (1 or 2 years). A subgroup propensity match and backward stepwise logistic regression model were utilized to control for surgical and radiographic differences in the cohorts. RESULTS Thirty-one patients (28.7%) were PLS+. There were no differences with regard to preoperative or final sagittal alignment parameters, number of levels fused (10.7±3.8 vs 9.7±3.8, p=0.331), and BMI (24.9±5.2 vs 27.0±6.9 kg/m2, p=0.143), though the PLS+ cohort was older (64.1±10.4 vs 51.3±21.4 years, p=0.002) and had greater 6-week corrections in sacral slope (SS), pelvic tilt (PT), pelvic incidence-lumbar lordosis (PI-LL), C7-S1 sagittal vertical axis (C7 SVA), and T1 pelvic angle (T1PA), p 0.05 for 6-week changes in SS, PT, LL, PI-LL, C7 SVA, T1PA, thoracic kyphosis, thoracolumbar kyphosis, and cervical lordosis), PLS augmentation was still not associated with a lower rate of PJK (29% PLS+ vs 38.7% PLS-, p=0.367). In our multivariate analysis, only increased sagittal malalignment and failure to restore sagittal balance were retained as having independent associations with PJK, while PLS+ was not retained in the model. CONCLUSIONS Even after controlling for relevant variables such as age, preoperative alignment, and degree of correction, PLS reinforcement at the UIV+1 did not reduce the incidence of PJK at 1 year. Our findings emphasize the multifactorial nature of PJK and the difficulty of preventing PJK with a single surgical technique FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.
A Door into Ocean as a Model for Feminist Science

Christy Tidwell notes that feminist science fiction often explores the possibility of a specifically feminist science. As a major example of feminist science fiction, A Door into Ocean neither rejects scientific ways of understanding the world nor condones prior scientific practices. This novel suggests that a feminist science would be defined by recognition of women’s scientific contributions, challenges to hierarchical and dichotomous modes of thought, and consideration of the political and ethical ramifications of its choices, narratives, and definitions. A Door into Ocean endorses elements of traditional science that are compatible with feminist goals while simultaneously exploring the possibility of a feminist science that does not yet fully exist.
To Degrade a MicroRNA, Destroy Its Argonaute Protein

Han et al. (2020) and Shi et al. (2020) report that the E3 ubiquitin ligase ZSWIM8 senses when an RNA and an Argonaute protein-bound microRNA are extensively base paired and directs Argonaute destruction by the proteasome. The result is degradation of the microRNA.
Clinical failure in abscess treatment: the role of ultrasound and incision and drainage.

Skin and soft tissue abscesses are commonly treated in emergency departments (ED). The use of bedside ultrasound may improve patient outcomes. The primary objective of this study was to examine the relationship between ultrasound use and risk of treatment failure in ED patients treated for abscesses. In this multi-center observational study, we reviewed medical records of adult patients evaluated for abscesses. Demographics, infection characteristics, treatments rendered, use of ultrasound (for diagnosis and/or treatment) and follow-up data were collected from electronic medical record review. Treatment failure, the primary outcome, was defined as any surgical intervention after the initial ED visit. Multivariable logistic regression tested whether incision and drainage utilizing ultrasound was associated with reduced treatment failure. We identified 609 patients diagnosed with abscesses over a 22-month period. Of them 75% were treated with incision and drainage, 55% had an ultrasound and 15% failed treatment. Multi-variable analysis demonstrated an 8% probability of failure with ultrasound plus incision and drainage, 14% with blind incision and drainage and 25% without incision and drainage. Individuals with incision and drainage performed were 50% less likely to fail treatment (RR 0.53, 95%CI 0.35–0.81) and 70% less likely to fail treatment (RR 0.30, 95%CI 0.18–0.51) with ultrasound and incision and drainage. The use of ultrasound in diagnosing and or/treating patients with abscesses in the ED is associated with decreased treatment failure risk when utilized with incision and drainage. Consideration of ultrasound use in other studies which assess treatment methods in relation to patient outcomes may be warranted.
NO x Pollutant Formation in Turbulent Coal Systems

In Chapter 11 we introduced the concept and problems associated with chemical reactions in turbulent flows. We noted that among the most important questions in current combustion research are those regarding the interactions between the turbulent fluid mechanics and the chemical reactions. The apparent random fluctuations in the turbulent mixing of the reactants and products dramatically influences mean chemical kinetic rates that have reaction time scales on the order of the turbulent time scale or less. We saw that essentially all homogeneous gas combustion lies in this critical area, including the combustion of methane and higher-order hydrocarbon constituents of natural gas.
An Approximate Solution and Master Curves for Buckling of Symmetrically Laminated Composite Cylinders

Nondimensional linear-bifurcation buckling equations for balanced, symmetrically laminated cylinders with negligible shell-wall anisotropies and subjected to uniform axial compression loads are presented. These equations are solved exactly for the practical case of simply supported ends. Nondimensional quantities are used to characterize the buckling behavior that consist of a stiffness-weighted length-to-radius parameter, a stiffness-weighted shell-thinness parameter, a shell-wall nonhomogeneity parameter, two orthotropy parameters, and a nondimensional buckling load. Ranges for the nondimensional parameters are established that encompass a wide range of laminated-wall constructions and numerous generic plots of nondimensional buckling load versus a stiffness-weighted length-to-radius ratio are presented for various combinations of the other parameters. These plots are expected to include many practical cases of interest to designers. Additionally, these plots show how the parameter values affect the distribution and size of the festoons forming each response curve and how they affect the attenuation of each response curve to the corresponding solution for an infinitely long cylinder. To aid in preliminary design studies, approximate formulas for the nondimensional buckling load are derived, and validated against the corresponding exact solution, that give the attenuated buckling response of an infinitely long cylinder in terms of the nondimensional parameters presented herein. A relatively small number of "master curves" are identified that give a nondimensional measure of the buckling load of an infinitely long cylinder as a function of the orthotropy and wall inhomogeneity parameters. These curves reduce greatly the complexity of the design-variable space as compared to representations that use dimensional quantities as design variables. As a result of their inherent simplicity, these master curves are anticipated to be useful in the ongoing development of buckling-design technology.
Empowering Latinos with Disabilities to Address Issues of Independent Living and Disability Rights: A Capacity-Building Approach

SUMMARY Latinos with disabilities have historically been underrep-resented in efforts to set the disability agenda and promote disability rights. This manuscript describes a capacity-building approach to community empowerment. Our goal was to empower Latinos with disabilities, increasing their degree of control over services and decisions that directly affect them. The capacity-building approach is grounded in a contextual/behavioral model of empowerment of people with disabilities. This approach emphasizes developing partnerships with local advocacy organizations and encourages active participation of people with disabilities and their families in identifying and addressing their own needs. Such capacity-building includes six major steps: (1) community entry and project planning; (2) identifying community concerns and strengths; (3) community organizing; (4) action planning; (5) monitoring and feedback; and (6) sustaining community organizing efforts. We illustrate the process with an example of an effor...
The Real Numbers

Toward the end of his distinguished career, the renowned British mathematician G.H. Hardy eloquently laid out a justification for a life of studying mathematics in A Mathematician’s Apology, an essay first published in 1940. At the center of Hardy’s defense is the thesis that mathematics is an aesthetic discipline. For Hardy, the applied mathematics of engineers and economists held little charm. “Real mathematics,” as he referred to it, “must be justified as art if it can be justified at all.”
Optimizing Stochastic Process for Efficient Microstructure Reconstruction

To improve the efficiency in microstructure reconstruction is critical to build a high resolution statistical stable representative volume element practically. Using correlation function to reconstruct image using simulated annealing is revisited in this study. Different cooling schedules in simulated annealing were utilized and compared. Dramatic increase of computation efficiency has been achieved by optimizing cooling schedule, making it feasible for future computation intensive study on upscaling prediction.
Regulation by molluscan myosins.

Molluscan myosins are regulated molecules that control muscle contraction by the selective binding of calcium. The essential and the regulatory light chains are regulatory subunits. Scallop myosin is the favorite material for studying the interactions of the light chains with the myosin heavy chain since the regulatory light chains can be reversibly removed from it and its essential light chains can be exchanged. Mutational and structural studies show that the essential light chain binds calcium provided that the Ca-binding loop is stabilized by specific interactions with the regulatory light chain and the heavy chain. The regulatory light chains are inhibitory subunits. Regulation requires the presence of both myosin heads and an intact headrod junction. Heavy meromyosin is regulated and shows cooperative features of activation while sub fragment-1 is non-cooperative. The myosin heavy chains of the functionally different phasic striated and the smooth catch muscle myosins are products of a single gene, the isoforms arise from alternative splicing. The differences between residues of the isoforms are clustered at surface loop-1 of the heavy chain and account for the different ATPase activity of the two muscle types. Catch muscles contain two regulatory light chain isoforms, one phosphorylatable by gizzard myosin light chain kinase. Phosphorylation of the light chain does not alter ATPase activity. We could not find evidence that light chain phosphorylation is responsible for the catch state. (Mol Cell Biochem 190: 55–62, 1999)
Alveolar PCO2 and PO2 in pregnant and nonpregnant women at high altitude.

Abstract The alveolar P CO 2 of a group of pregnant women residing at an altitude of 14,500 feet was compared with that of a group of nonpregnant women residing at the same altitude. Pregnancy is associated with a hyperventilatory effect over and above the hyperventilation already existent on the basis of residence at altitude.
The Foreign Corrupt Practices Act & Corporate Philanthropy: Rethinking the Regulations

American companies bring US innovation and capital to all corners of the globe. The US corporate presence abroad is seen not only in oil rigs and factories, but also in corporate development projects and humanitarian relief efforts. When the 2010 earthquake hit Port-au-Prince, Haiti, US companies donated over $146.8 million to the relief effort. Despite this impressive display of global engagement, commentators suggested that the US anti-corruption laws had discouraged corporations from greater involvement. Even with the laws in force, however, reports of corruption in the relief effort soon surfaced, derailing Haiti’s recovery. Foreign aid that feeds corruption will never achieve sustainable growth, but development efforts will similarly fail if US anti-corruption laws discourage corporate philanthropy.This Comment analyzes the application of the Foreign Corrupt Practices Act (“FCPA”) to international corporate charity. It shows how the FCPA’s ambiguous nature has the unfortunate effect of being both over- and under-inclusive, discouraging bona fide charity while at the same time failing to capture corrupt donations. This Comment proposes a modification to FCPA enforcement: creating a Safe Harbor Option. This will offer businesses the opportunity to “buy” a rebuttable presumption of legitimacy for their charitable donations by publically disclosing the payments, projects, and recipients of their philanthropy. Granting a presumption of legitimacy to disclosed donations will ameliorate many of the over-inclusive aspects of the FCPA. The increased disclosure will allow the public to monitor corporate charity and question suspicious gifts, ameliorating the under-inclusive aspects of FCPA enforcement.A greater emphasis on disclosure-based anti-corruption law will encourage robust and honest corporate philanthropy that will support long-lasting and sustainable development around the world.
Nuclear Medicine in Pediatric Urology and Nephrology

Renal scintigraphy is a diagnostic procedure of choice or a complementary imaging modality in the work up of infants and children with urologic or nephrologic problems. New radiopharmaceuticals and techniques and expert interpretation provide unique renal parenchymal and collecting system functional and anatomical information, which helps in the diagnosis and follow up of congenital or acquired kidney disorders and the quantitation of renal function. Education of the user and the referring physician, further clinical experience, and comparative studies should help increase utilization of renal scintigraphy in the neonatal and pediatric age for the benefit of the patient and the better understanding of urologic and nephrologic disorders.
A review of mild traumatic brain injury diagnostics: current perspectives, limitations, and emerging technology.

ABSTRACT Mild traumatic brain injury (mTBI) or concussion is a common battlefield and in-garrison injury caused by transmission of mechanical forces to the head. The energy transferred in such events can cause structural and/or functional changes in the brain that manifest as focal neurological, cognitive, or behavioral dysfunction. Current diagnostic criteria for mTBI are highly limited, variable, and based on subjective self-report. The subjective nature of the symptoms, both in quantity and quality, together with their large overlap in other physical and behavioral maladies, limit the clinician's ability to accurately diagnose, treat, and make prognostic decisions after such injuries. These diagnostic challenges are magnified in an operational environment as well. The Department of Defense has invested significant resources into improving the diagnostic tools and accuracy for mTBI. This focus has been to supplement the clinician's examination with technology that is better able to objectify brain dysfu...
Towards closing the watershed nitrogen budget: Spatial and temporal scaling of denitrification

[1] Enhanced consideration of the hydrogeomorphic template of watersheds is critical to understanding watershed nitrogen budgets. We developed a framework to estimate the spatial distribution and temporal dynamics of soil moisture and soil oxygen in surficial soils to scale nitrogen transformations for a forested watershed (Pond Branch) in Maryland, USA. We sampled soil cores in upland, hillslope hollow, riparian hollow, and riparian hummock landscape positions in different seasons for biogeochemical fluxes including measurement of N2 gas produced via denitrification. We extrapolated these rates in space and time with information derived from in situ soil oxygen and soil moisture probes to scale fluxes from plots to the catchment level. We addressed three questions: (1) How important are seasonal, daily, and storm event variations in soil oxygen for denitrification? (2) How is denitrification spatially distributed through the watershed? (3) How important is denitrification to the watershed nitrogen budget? We found that microtopography within the riparian zone is a significant influence on soil oxygen dynamics and therefore redox-sensitive biogeochemical processes such as denitrification. Riparian zone hollows (lower topographic positions) represented 0.5%–1.0% of the catchment area, but accounted for >99% of total denitrification. Interestingly, topography was a much stronger controller of oxygen than rainfall, which had little influence on temporal variation in soil oxygen levels. Spatial and temporal extrapolations of measured rates suggest that a minimum of 16%–27% of atmospheric nitrogen deposition is lost to denitrification. These results suggest that the importance of denitrification in the nitrogen budget of forested watersheds depends fundamentally on the presence of landscape elements, such as riparian hollows that function as “hot spots” of activity.
Is polyphenol induction simply a result of altered carbon and nitrogen accumulation

Carbon translocation in plants is shaped by phyllotaxis and regulated by source/sink interactions that respond to the demands of growth and defense. We have studied this extensively in poplar saplings, and recently showed that unlike carbon import, nitrogen is not translocated to sink leaves in response to application of jasmonic acid. Here we report that this is also true for young trees in the field. We discuss the importance of transport processes in establishing local C:N ratios, and suggest that the JA-induced flow of C but not N to sink tissues, and their corresponding increases in C-based defenses, may simply reflect a plant adaptation to handle excess reduced carbon and energy.
Phylogenetic comparisons of the branched-chain α-ketoacid dehydrogenase complex

Abstract 1. 1. Antibodies agains the E 1b and E 2b components of bovine branched-chain α-ketoacid (BCKA) dehydrogenase (BCKAD) complex completely inhibited BCKA oxidation in mammalian and avian mitochondria. BCKA oxidation by salmonid mitochondria was less affected and the enzyme from Pseudomonas putida was unaffected. 2. 2. In rodents, anti-E 1b E 2b IgG inhibited oxidation of all three BCKA in a similar dose-dependent manner; oxidation of α-ketobutyrate and α-keto-γ-methiolbutyrate was also partially inhibited. 3. 3. Except for the salmonid BCKAD, a similar M r for the E 2b and E 1bα proteins was observed in these species. 4. 4. After digestion with V-8 protease similar immunoreactive peptides were observed for the human and rodent complex.
ICP Emission Spectrometry: On the Selection of Analytical Lines, Line Coincidence Tables, and Wavelength Tables:

A thorough knowledge of the spectral emission characteristics of the inductively coupled plasma is a prerequisite for its maximum utilization in atomic emission spectroscopy. Toward this end an Atlas of Spectral Information for Inductively Coupled Plasma, Atomic Emission Spectroscopy has been assembled to provide the analyst with the basic information concerning the analytical capabilities and the potential spectral interferences of the prominent spectral lines of 70 elements. The Atlas contains 232 wavelength scans of 70 elements covering the range of 189 to 517 nm (189 to 597 nm for sodium and the reference blank). The Atlas also contains a listing of 973 prominent lines with estimated detection limits and a detailed collection of coincidence profiles for 281 of the most prominent lines, each with profiles of ten of the most prevalent concomitant elements superimposed. This paper contains a survey of the spectral information contained in the Atlas.
Chemical and mechanical performance of flexible magnetic tape containing chromium dioxide

The development of a magnetic-recording tape using chromium dioxide suitable for use with the tape drive of the IBM 3480 Magnetic Tape Subsystem was found to require careful optimization of the chemical and mechanical properties of the coating. This paper discusses the role of chromium dioxide in the oxidative and hydrolytic degradation of the polyester-polyurethane binders used in most flexible tape coatings, and the subsequent necessity for careful binder selection to eliminate (for all practical purposes) these degradative effects. In addition to the chemical behavior, the paper discusses the role of the interaction of the chromium dioxide with the binder necessary to obtain mechanical performance suitable for the 3480 tape drive. A high modulus and a relatively high glass-transition temperature were found to be required to avoid changes in the frictional properties of the tape. The incorporation of a rough-textured back coat was found to control the change in the surface topography of the recording surface near the spool hub which arises as a result of compressive forces.
Early Expression of Parkinson’s Disease-Related Mitochondrial Abnormalities in PINK1 Knockout Rats

PTEN-induced kinase 1 (PINK1) mutations are responsible for an autosomal recessive, familial form of Parkinson’s disease. PINK1 protein is a Ser/Thr kinase localized to the mitochondrial membrane and is involved in many processes including mitochondrial trafficking, mitophagy, and proteasomal function. Using a new PINK1 knockout (PINK1 KO) rat model, we found altered brain metabolomic markers using magnetic resonance spectroscopy, identified changes in mitochondrial pathways with quantitative proteomics using sequential window acquisition of all theoretical spectra (SWATH) mass spectrometry, and demonstrated mitochondrial functional alterations through measurement of oxygen consumption and acidification rates. The observed alterations included reduced creatine, decreased levels of complex I of the electron transport chain, and increased proton leak in the electron transport chain in PINK1 KO rat brains. In conjunction, these results demonstrate metabolomic and mitochondrial alterations occur during the asymptomatic phase of Parkinson’s disease in this model. These results indicate both potential early diagnostic markers and therapeutic pathways that can be used in PD.
The rescaling method for quantifying the turnover of cell populations

The dynamic nature of immune responses requires the development of appropriate experimental and theoretical tools to quantitatively estimate the division and death rates which determine the turnover of immune cells. A number of papers have used experimental data from BrdU and D-glucose labels together with a simple random birth-death model to quantify the turnover of immune cells focusing on HIV/SIV infections [Mohri et al. 279 (1998) 1223-1227, Hellerstein et al. 5 (1999) 83-89, Bonhoeffer et al. 164 (2000) 5049-5054, Mohri et al. 87 (2001) 1277-1287]. We show how uncertainties in the assumptions of the random birth-death model may lead to substantial errors in the parameters estimated. We then show how more accurate estimates can be obtained from the more recent CFSE data which allow to track the number of divisions each cell has undergone. Specifically, we: (i) describe a general stage-structured model of cell division where the probabilities of division and death are functions of time since the previous division; (ii) develop a rescaling method to identify invariant parameters (i.e. the ones that are independent of the specific functions describing division and death); (iii) show how these invariant parameters can be estimated, and (iv) illustrate this technique by applying it to CFSE data taken from the literature.
Networked Handhelds for Collaborative Sense-Making in Undergraduate Physics

Classroom networks of handheld devices have the potential to support a new genre of collaborative learning activities, enabling complex small group tasks that encourage and support the simultaneous engagement of all students. At the same time, one-to-one personal computing with intuitive touchscreen interfaces offers engaging simulations and visualization aids to individual learners. However, it is not well understood how to design effective simulations to be used by and to engage groups of students in a collaborative setting. My dissertation work is an exploration of the collaborative physics activity design space opened up by networked handheld devices. Specifically, I study the design of networked simulations with the aim of engaging students in high-level discourse about physics concepts.
Radiology of the pancreas, gallbladder, and biliary tract

Over the last decade, there have been significant advances in imaging benign and malignant diseases of the pancreas, gallbladder, and biliary tract. Multidetector helical CT, ultrasound, MR imaging with MR cholangiography, endoscopic ultrasound and ERCP with therapeutic intervention, minimally invasive surgery, and interventional radiology have all made prompt diagnosis and intervention possible. I am fortunate to have outstanding authors, all experts in their fields, provide state-of-the-art reviews for this issue of the Radiologic Clinics of North America. Dr. Balthazar discusses staging and complications of acute pancreatitis in two articles. Drs. Remer and Baker review chronic pancreatitis including CT, ERCP, and the more recent techniques, MR, MRCP, and endoscopic ultrasound. Drs. Hammond and Miller discuss the importance of cystic masses of the pancreas and how to differentiate them. Drs. Horton and Fishman demonstrate the use of multidetector CT, including CT angiography, and the role of 3D imaging to identify adenocarcinoma of the pancreas and demonstrate vascular invasion. Drs. Sheth and Fishman discuss the less common but certainly important tumors of the pancreas. Drs. Ly and Miller discuss recent advance in MR of the pancreas. Dr. Gore and his coauthors provide a multimodality evaluation of diseases of the gallbladder. Drs. Baron, Tublin, and Peterson provide a practical approach to benign and malignant biliary diseases. Dr. Benya discusses important pancreatic and biliary diseases of children. Drs. Fulcher and Turner emphasize the importance of MRCP in the evaluation of biliary pathology. Dr. Kochman and colleagues emphasize the use of endoscopic ultrasound and therapeutic ERCP from the perspective of gastroenterologists. Drs. Talamonti and Denham wrap up the issue with the surgical perspective of how advances in surgery have paralleled the advances in imaging. I would like to thank this talented group of authors for their excellent contributions; they have made editing this issue a pleasure. I would also like to thank Barton Dudlick and W.B. Saunders for inviting me to develop this project and for their assistance in ensuring its completion. I want to especially thank my wife, Michelle, and son, Scott, for their constant support. I would like to dedicate this edition to my late father, Dr. Sheldon Miller, whose love of radiology has been an inspiration for me.
Structural Basis for the BRCA1 BRCT Interaction with the Proteins ATRIP and BAAT1.

The breast and ovarian cancer susceptibility protein 1 (BRCA1) plays a central role in DNA damage response (DDR). Two tandem BRCA1 C-terminal (BRCT) domains interact with several proteins that function in DDR and contain the generally accepted motif pS-X-X-F (pS denoting phosphoserine and X any amino acid), including the ATR-interacting protein (ATRIP) and the BRCA1-associated protein required for ATM activation-1 (BAAT1). The crystal structures of the BRCA1 BRCTs bound to the phosphopeptides ATRIP (235–PEACpSPQFG–243) and BAAT1 (266–VARpSPVFSS–274) were determined at 1.75 A and 2.2 A resolution, respectively. The pSer and Phe(+3) anchor the phosphopeptides into the BRCT binding groove, with adjacent peptide residues contributing to the interaction. In the BRCA1–ATRIP structure, Gln(+2) is accommodated through a conformational change of the BRCA1 E1698 side chain. Importantly, isothermal titration calorimetry experiments showed that the size and charge of the side chains at peptide positions +1 and +2 con...
Origins of invasive piscivores determined from the strontium isotope ratio (87Sr/86Sr) of otoliths.

We examined strontium isotope ratios (87Sr/86Sr) in fish otoliths to determine the origins of invasive piscivores in the Upper Colorado River Basin (UCRB, western USA). We examined 87Sr/86Sr from f...
Density measurements of the lithium fluoride/lithium sulfide eutectic at high temperature

A straightforward and reliable method to determine densities of molten salts at high temperatures was de-veloped by Janz and Lorenz several years ago.[1] This method was followed in order to determine the density of the LiF/Li2S eutectic[2] over the temperature range of 1176 to 1355 K in which the eutectic is liquid. The rel-ative lack of data for this eutectic is surprising given its potential usefulness in the study of advanced batteries'31 and electrowinning of metals from molten sulfides.[41] The method is based on the fact that a solid piece of metal of known volume suspended from a pan balance into a molten salt will weigh less than if it were sus-pended in air at the same temperature. This difference in weight measured in grams will be equal to the buoyant force of the liquid at that temperature. The density of the salt bath can then readily be determined by dividing this difference by the volume of the solid piece of metal that is immersed in the bath. The procedure can be re-peated to give density values over a range of temperatures.
Seasonal Variation in Catch Rate and Body Condition for Four Fish Species in a South Dakota Natural Lake

ABSTRACT Seasonal variation in catch rate (catch per unit effort, CPUE) and body condition (relative weight, Wr) for northern pike Esox lucius, black crappie Pomoxis nigromaculatus, yellow perch Perca flavescens, and walleye Stizostedion vitreum sampled with trap (modified fyke) nets was evaluated in Lake Madison, a natural lake in eastern South Dakota, from March through October, 1990. Seasonal variation in CPUE and Wr occurred for all fish species. Northern pike CPUE declined from spring until fall. Black crappie CPUE was highest in the spring and fall. Yellow perch and walleye CPUE peaked during the summer. Seasonal variation in mean Wrwas similar for all fish species—mean Wr declined from spring to early summer then increased until early fall. Fisheries biologists should consider seasonal variation associated with CPUE and Wr during the assessment of sampling data.
Effect of applied force and blade speed on histopathology of bone during resection by sagittal saw

Abstract A sagittal saw is commonly used for resection of bone during joint replacement surgery. During sawing, heat is generated that can lead to an increase in temperature at the resected surface. The aim of this study was to determine the effect of applied thrust force and blade speed on generating heat. The effect of these factors and their interactions on cutting temperature and bone health were investigated with a full factorial Design of Experiments approach for two levels of thrust force, 15N and 30N, and for two levels of blade oscillation rate, 12,000 and 18,000 cycles per minute (cpm). In addition, a preliminary study was conducted to eliminate blade wear as a confounding factor. A custom sawing fixture was used to crosscut samples of fresh bovine cortical bone while temperature in the bone was measured by thermocouple ( n =40), followed by measurements of the depth of thermal necrosis by histopathological analysis ( n =200). An analysis of variance was used to determine the significance of the factor effects on necrotic depth as evidenced by empty lacunae. Both thrust force and blade speed demonstrated a statistically significant effect on the depth of osteonecrosis ( p p =0.22). The minimum necrotic depth observed was 0.50mm, corresponding to a higher level of force and blade speed (30N, 18,000cpm). Under these conditions, a maximum temperature of 93°C was measured at 0.3mm from the kerf. With a decrease in both thrust force and blade speed (15N, 12,000cpm), the temperature in the bone increased to 109°C, corresponding to a nearly 50% increase in depth of the necrotic zone to 0.74mm. A predictive equation for necrotic depth in terms of thrust force and blade speed was determined through regression analysis and validated by experiment. The histology results imply that an increase in applied thrust force is more effective in reducing the depth of thermal damage to surrounding bone than an increase in blade speed.