cssi/SciSciGPT-SciSciNet huggingface dataset:
What the Baldwin Effect affects depends on the nature of plasticity.

Abstract In a process known as the Baldwin Effect, developmental plasticity, such as learning, has been argued to accelerate the biological evolution of high-fitness traits, including language and complex intelligence. Here we investigate the evolutionary consequences of developmental plasticity by asking which aspects of a plastic trait are the focus of genetic change. The aspects we consider are: (i) dependencies between elements of a trait, (ii) the importance of each element to fitness, and (iii) the difficulty of acquiring each element through plasticity. We also explore (iv) how cultural inheritance changes the relationship between plasticity and genetic change. We find that evolution by natural selection preferentially fixes elements that are depended upon by others, important to fitness, or difficult to acquire through plasticity, but that cultural inheritance can suppress and even reverse genetic change. We replicate some of these effects in experimental evolutionary simulations with human learners. We conclude that what the Baldwin Effect affects depends upon the mechanism of plasticity, which for behavior and cognition includes the psychology of learning.
Printing and mounting digital casts in the centric relation position for use on an analog articulator: A dental technique

Abstract A technique for recording, printing, and mounting digital casts in centric relation is described. Combining elements of analog and digital workflows, centric relation records can be transferred by digital scanning and used to align casts for articulation. This method is useful to the clinician adapting to digital workflow or preferring a physical semiadjustable articulator in conjunction with digital scans.
Rural and urban disparities based on zip code of residence: Analyses of 834 and 2,159 patients in NCCTG N9741 and CALGB 80405 (Alliance) trials respectively.

e16076Background: Median overall survival (mOS) of patients (pt) with metastatic colorectal cancer (mCRC) has improved steadily over the past two decades. However, epidemiological data suggest that...
Solid solutions with coexisting ferroelectric and antiferroelectric phases for creation of new materials

The controlled decomposition of solid solutions in the vicinity of interphase boundaries separating domains of the coexisting antiferroelectric and ferroelectric phases opens new fields of applications for these materials. The lead zirconate–titanate based solid solutions are considered as an example of substances suitable for creation of materials with the negative refractive index. Manufactured composites constitute a dielectric antiferroelectric matrix with a structure of conducting interphase boundaries separating domains of the ferroelectric and antiferroelectric phases. The electric conductivity of the interphase boundaries occurs as a result of the local decomposition of the solid solutions in the vicinity of these boundaries. The decomposition process and consequently the conductivity of the interphase boundaries can be controlled by means of external influences.
Aging and chronic high-fat feeding negatively affect kidney size, function, and gene expression in CTRP1-deficient mice

C1q/TNF-related protein 1 (CTRP1) is an endocrine factor with metabolic, cardiovascular, and renal functions. We previously showed that aged Ctrp1-knockout (KO) mice fed a control low-fat diet deve...
Reinforcement of PMMA bone cement with a continuous wire coil--a canine femur study

The hoop and axial strains present due to loading after femoral stem implantation in canine femurs, implanted with and without a wire coil surrounding the distal tip were investigated. One stem served as the control without wire coil while the other was experimental reinforced with a wire coil. Both stems were implanted by identical methods. Ideally, the wire coil should serve to reduce the hoop and axial strains present in the distal tip of the arthroplasty. The strains were measured using 90 degrees rosette strain gages. Though the coil's position was altered slightly during implantation usable results were still obtained. At a maximum load of 44.5 N there were 32 and 19% reduction in the hoop and axial strains for the reinforced stem and the control, respectively. This experiment presents a striking difference between the control and reinforced hip arthroplasties. Equally important is that this study confirms the trends in hoop and axial strain behavior demonstrated in other works utilizing a wire coil reinforcement scheme. The simple method of applying a continuous wire coil may help to reduce the loosening of femoral stem of total hip arthroplasty by reducing strains at the tip of the stem due to the strengthening of the cement mantle.
Bone Metabolism in Adolescents Undergoing Bariatric Surgery

PURPOSE The prevalence of childhood obesity has increased over past decades with a concomitant increase in metabolic and bariatric surgery (MBS). While MBS in adults is associated with bone loss, only a few studies have examined the effect of MBS on the growing skeleton in adolescents. METHODS This mini-review summarizes available data on the effects of the most commonly performed MBS (sleeve gastrectomy and gastric bypass) on bone in adolescents. A literature review was performed using PubMed for English-language articles. RESULTS Dual-energy x-ray absorptiometry (DXA) measures of areal bone mineral density (aBMD) and BMD Z scores decreased following all MBS. Volumetric BMD (vBMD) by quantitative computed tomography (QCT) decreased at the lumbar spine while cortical vBMD of the distal radius and tibia increased over a year following sleeve gastrectomy (total vBMD did not change). Reductions in narrow neck and intertrochanteric cross-sectional area and cortical thickness were observed over this duration, and hip strength estimates were deleteriously impacted. Marrow adipose tissue (MAT) of the lumbar spine increased while MAT of the peripheral skeleton decreased a year following sleeve gastrectomy. The amount of weight loss and reductions in lean and fat mass correlated with bone loss at all sites, and with changes in bone microarchitecture at peripheral sites. CONCLUSION MBS in adolescents is associated with aBMD reductions, and increases in MAT of the axial skeleton, while sleeve gastrectomy is associated with an increase in cortical vBMD and decrease in MAT of the peripheral skeleton. No reductions have been reported in peripheral strength estimates.
An Economic Analysis of Biproportional Properties in an Input‐Output System

Various methods, such as biproportional adjustment and econometric estimating have been used to generate time series for input-output tables. In this paper, temporal changes of input-output coefficients are examined in order to analyze their behavior. Within the Chicago Region Econometric Input-Output Model, a set of input- output relationships has been extracted analytically for the period 1980-1997. Using the empirical evidence for Chicago, this paper conducts econometric time series analysis to determine whether or not certain coefficients or sets of coefficients exhibit tendencies toward stability or predictable change or whether others require more extensive economet- ric estimation.
Kv4.3 Channel Dysfunction Contributes to Trigeminal Neuropathic Pain Manifested with Orofacial Cold Hypersensitivity in Rats

Trigeminal neuropathic pain is the most debilitating pain disorder but current treatments including opiates are not effective. A common symptom of trigeminal neuropathic pain is cold allodynia/hyperalgesia or cold hypersensitivity in orofacial area, a region where exposure to cooling temperatures are inevitable in daily life. Mechanisms underlying trigeminal neuropathic pain manifested with cold hypersensitivity are not fully understood. In this study, we investigated trigeminal neuropathic pain in male rats following infraorbital nerve chronic constrictive injury (ION-CCI). Assessed by the orofacial operant behavioral test, ION-CCI animals displayed orofacial cold hypersensitivity. The cold hypersensitivity was associated with the hyperexcitability of small-sized trigeminal ganglion (TG) neurons that innervated orofacial regions. Furthermore, ION-CCI resulted in a reduction of A-type voltage-gated K+ currents (IA currents) in these TG neurons. We further showed that these small-sized TG neurons expressed Kv4.3 voltage-gated K+ channels, and Kv4.3 expression in these cells was significantly downregulated following ION-CCI. Pharmacological inhibition of Kv4.3 channels with phrixotoxin-2 inhibited IA-currents in these TG neurons and induced orofacial cold hypersensitivity. On the other hand, pharmacological potentiation of Kv4.3 channels amplified IA currents in these TG neurons and alleviated orofacial cold hypersensitivity in ION-CCI rats. Collectively, Kv4.3 downregulation in nociceptive trigeminal afferent fibers may contribute to peripheral cold hypersensitivity following trigeminal nerve injury, and Kv4.3 activators may be clinically useful to alleviate trigeminal neuropathic pain.SIGNIFICANCE STATEMENT Trigeminal neuropathic pain, the most debilitating pain disorder, is often triggered and exacerbated by cooling temperatures. Here, we created infraorbital nerve chronic constrictive injury (ION-CCI) in rats, an animal model of trigeminal neuropathic pain to show that dysfunction of Kv4.3 voltage-gated K+ channels in nociceptive-like trigeminal ganglion (TG) neurons underlies the trigeminal neuropathic pain manifested with cold hypersensitivity in orofacial regions. Furthermore, we demonstrate that pharmacological potentiation of Kv4.3 channels can alleviate orofacial cold hypersensitivity in ION-CCI rats. Our results may have clinical implications in trigeminal neuropathic pain in human patients, and Kv4.3 channels may be an effective therapeutic target for this devastating pain disorder.
Antarctic Water Tracks: Microbial Community Responses to Variation in Soil Moisture, pH, and Salinity

Ice-free soils in the McMurdo Dry Valleys select for taxa able to cope with challenging environmental conditions, including extreme chemical water activity gradients, freeze-thaw cycling, desiccation, and solar radiation regimes. The low biotic complexity of Dry Valley soils makes them well suited to investigate environmental and spatial influences on bacterial community structure. Water tracks are annually wetted habitats in the cold-arid soils of Antarctica that form briefly each summer with moisture sourced from snow melt, ground ice thaw, and atmospheric deposition via deliquescence and vapor flow into brines. Compared to neighboring arid soils, water tracks are highly saline and relatively moist habitats. They represent a considerable area (∼5-10 km2) of the Dry Valley terrestrial ecosystem, an area that is expected to increase with ongoing climate change. The goal of this study was to determine how variation in the environmental conditions of water tracks influences the composition and diversity of microbial communities. We found significant differences in microbial community composition between on- and off-water track samples, and across two distinct locations. Of the tested environmental variables, soil salinity was the best predictor of community composition, with members of the Bacteroidetes phylum being relatively more abundant at higher salinities and the Actinobacteria phylum showing the opposite pattern. There was also a significant, inverse relationship between salinity and bacterial diversity. Our results suggest water track formation significantly alters dry soil microbial communities, likely influencing subsequent ecosystem functioning. We highlight how Dry Valley water tracks could be a useful model system for understanding the potential habitability of transiently wetted environments found on the surface of Mars.
Effect of redundant clinical trials from mainland China evaluating statins in patients with coronary artery disease: cross sectional study.

Abstract Objective To identify redundant clinical trials evaluating statin treatment in patients with coronary artery disease from mainland China, and to estimate the number of extra major adverse cardiac events (MACEs) experienced by participants not treated with statins in those trials. Design Cross sectional study. Setting 2577 randomized clinical trials comparing statin treatment with placebo or no treatment in patients with coronary artery disease from mainland China, searched from bibliographic databases to December 2019. Participants 250 810 patients with any type of coronary artery disease who were enrolled in the 2577 randomized clinical trials. Main outcome measures Redundant clinical trials were defined as randomized clinical trials that initiated or continued recruiting after 2008 (ie, one year after statin treatment was strongly recommended by clinical practice guidelines). The primary outcome is the number of extra MACEs that were attributable to the deprivation of statins among patients in the control groups of redundant clinical trials—that is, the number of extra MACEs that could have been prevented if patients were given statins. Cumulative meta-analyses were also conducted to establish the time points when statins were shown to have a statistically significant effect on coronary artery disease. Results 2045 redundant clinical trials were identified published between 2008 and 2019, comprising 101 486 patients in the control groups not treated with statins for 24 638 person years. 3470 (95% confidence interval 3230 to 3619) extra MACEs were reported, including 559 (95% confidence interval 506 to 612) deaths, 973 (95% confidence interval 897 to 1052) patients with new or recurrent myocardial infarction, 161 (132 to 190) patients with stroke, 83 (58 to 105) patients requiring revascularization, 398 (352 to 448) patients with heart failure, 1197 (1110 to 1282) patients with recurrent or deteriorated angina pectoris, and 99 (95% confidence interval 69 to 129) unspecified MACEs. Conclusions Of more than 2000 redundant clinical trials on statins in patients with coronary artery disease identified from mainland China, an extra 3000 MACEs, including nearly 600 deaths, were experienced by participants not treated with statins in these trials. The scale of redundancy necessitates urgent reform to protect patients.
Hybrid Bessel beam and metamaterial lenses for deep laparoscopic nondestructive evaluation

A unique non-diffracting hybrid order longitudinal Bessel beam with pronounced resilience to scattering using acoustic metamaterial, which we call hybrid Bessel beams (HYBEs), is currently unknown. Newly proposed hybrid Bessel beams are different than the conventional cross-sectional Bessel beams. In this article, we explain the physics of multifunctional ultrasonic capabilities of a bioinspired interlocking architecture of acoustic metamaterial. At first, for the newly proposed metastructure, understanding the physics and wave energy is predictively focused through attenuative surfaces at various ultrasonic frequencies (∼120 to ∼130 kHz). Finally, a zero-order first of its kind ultrasonic Bessel-like beam between frequencies of ∼265 and ∼272 kHz is shown propagating a long distance through the base material. The new propagation had minimal reduction in energy amplitude, while the displacement was nearly constant across the depth of the wave guide following a second-order Bessel function of the first kind. To explain the physics of the phenomena, mode shapes in the frequency-wavenumber domain are investigated. Furthermore, identification of the propagating wave vector using equi-frequency contours at multiple ranges confirmed the presence of the proposed acoustic features. These abilities of the proposed metamaterial have key advantages to propagate waves deeper into thick attenuative and aberrative structures such as brain tissue, soft skin and muscles, paint surface, and non-accessible composite materials. We envision potential applications of the proposed HYBE for the non-destructive evaluation (NDE) of attenuative materials that are not easily accessible for testing. To verify the wave focusing and long-distance wave propagation, an ad hoc metamaterial lens for the conventional NDE transducer is proposed, which demonstrated wave propagation through a 10 mm thick carbon fiber reinforced polymer composite structure.
Compressions for Portal Vein Air Embolism Evacuation

Laparoscopic entry into the abdomen with subsequent insufflation can be achieved via an open or closed approach. A risk that is often overlooked as a result of its rarity is a venous air embolism (VAE) from carbon dioxide (CO 2 ) insufflation. Although both closed and open techniques of entry into the abdomen contribute to an extremely low risk for VAE, when the effects are clinically significant the mortality rate has been reported to be as high as 28%. In this report we present a case of a 64-year-old female who underwent a closed approach for entry into the abdomen for elective hepatic cystectomy, who subsequently went into cardiopulmonary arrest and was found to have imaging findings suggestive of VAE localized to the portal vein. Successful management decisions presented in this case report will serve as possible options for physicians to employ when encountering a similar intraoperative complication. J Curr Surg. 2021;11(2):42-45 doi: https://doi.org/10.14740/jcs436
County-Level Determinants of COVID-19 Testing and Cases: Are there Racial/Ethnic Disparities in Texas?

Reports suggest that COVID-19 affects people of color disproportionately. Texas ranks second in the count of confirmed US cases. This study examined the relationship between county-level racial/eth...
Some of the Difficulties in the Diagnosis of Cancer of the Internal Organs

Excerpt In 1927, 14,254 people died of cancer in the State of New York. Of these deaths, 7,448 or 52.2 per cent occurred in the City of New York, and 6,806 or 47.8 per cent occurred in the remainde...
Chapter 15 HHV-6 in atypical polyclonal lymphoproliferation (APL) and malignant lymphomas

Publisher Summary Human herpesvirus-6 (HHV-6) is the second member of the human herpesvirus family with pronounced lymphotropism. It resembles in many clinical aspects the Epstein–Barr virus (EBV; HHV-4) although the lymphoid target cell for infection and replication differs in both viruses. This chapter gives an overview of the current knowledge of HHV-6 and its suggestive relationship to progressive and malignant lymphoproliferative diseases. This chapter also describes atypical polyclonal lymphoproliferation (APL) that has been proposed for lymphoproliferative disorders which clinically mimic malignant lymphomas but are missing the criterion of monoclonality. A diagrammatic representation of the characteristic histological appearance of cases of APL is given in the chapter.
AN APPLICATION OF FOKKER-PLANCK EQUATION TO JOSEPHSON JUNCTION

Abstract A long Josephson junction can be modeled by a perturbed sine–Gordon equation. Based on a soliton perturbation theory, the probability distribution of the velocity of a single soliton, at the presence of a white noise contained in bias current, is studied by the Fokker–Planck method. This approach can be extended to the study of multisolitons.
Studying the effect of drilling uncertainty on signal propagation through vias

A differential via structure with four varying factors are defined in this paper. The Monte Carlo (MC), stochastic collocation (SC) and design of experiments (DoE) methods are employed to quantify the drilling uncertainties in the abovementioned via structure. A comparison of the results shows that the SC method is more robust and can more efficiently and accurately estimate the mean and the standard deviation of the responses, compared to the DoE method.
Chapter 10 The Interaction of Mitochondrial Membranes with Reactive Oxygen and Nitrogen Species

Abstract Within the context of the overall effects of free radicals (ROS and RNS) on biological membranes, the mitochondrion offers a unique biochemical environment which leads to a number of organelle-specific reactions, This includes a unique complement of membrane lipids and proteins, an alkaline pH in the matrix, specialized systems for the generation and quenching of ROS and RNS, and a tightly controlled redox status. All of these parameters come together in a highly orchestrated system that is essential to the proper functioning of the mitochondrion. This chapter will examine some of the mitochondria-specific aspects of ROS and RNS reactions with membranes, within the context of the many disease processes that originate at the organelle level.
Prognosis for patients with metastatic breast cancer who achieve a no-evidence-of-disease status after systemic or local therapy.

BACKGROUND This study sought to determine outcomes for patients with metastatic breast cancer (MBC) with no evidence of disease (NED) after treatment and to identify factors predictive of outcomes once the status of NED was attained. METHODS This study reviewed 570 patients with MBC who were consecutively treated between January 2003 and December 2005. Ninety patients (16%) attained NED, which was defined as a complete metabolic response on positron emission tomography or sclerotic healing of bone metastases on computed tomography or magnetic resonance imaging. The median follow-up for patients attaining NED was 100 months (range, 14-134 months). RESULTS The 3- and 5-year overall survival (OS) rates were 44% and 24%, respectively, for the entire group and 96% and 78%, respectively, for those attaining NED. According to a landmark analysis, NED status was significantly associated with survival at 2 (P < .001; hazard ratio [HR], 0.23; 95% confidence interval [CI], 0.16-0.34) and 3 years (P < .001; HR, 0.20; 95% CI, 0.14-0.30). From the time of NED, the median survival was 102 months (range, 14-134 months) with 5-year OS and progression-free survival (PFS) rates of 77% and 40%, respectively. According to a multivariate analysis, human epidermal growth factor receptor 2 positivity was significantly associated with OS in comparison with estrogen receptor positivity (P = .02; HR, 0.44; 95% CI, 0.21-0.90), and trastuzumab use was significantly associated with PFS (P = .007; HR, 0.48; 95% CI, 0.28-0.82). Thirty-one patients (34%) with NED remained in remission at the last follow-up. CONCLUSIONS MBC patients who attain the status of NED have significantly prolonged survival with a durable response to therapy. Ultimately, this study provides essential outcome data for clinicians and patients living with MBC. Cancer 2015;121:4324–32. © 2015 American Cancer Society.
Sensitivity Analysis for Selection bias and unmeasured Confounding in missing Data and Causal inference models

In both observational and randomized studies, subjects commonly drop out of the study (i.e., become censored) before end of follow-up. If, conditional on the history of the observed data up to t, the hazard of dropping out of the study (i.e., censoring) at time t does not depend on the possibly unobserved data subsequent to t, we say drop-out is ignorable or explainable (Rubin, 1976). On the other hand, if the hazard of drop-out depends on the possibly unobserved future, we say drop-out is non-ignorable or, equivalently, that there is selection bias on unobservables. Neither the existence of selection bias on unobservables nor its magnitude is identifiable from the joint distribution of the observables. In view of this fact, we argue that the data analyst should conduct a “sensitivity analysis” to quantify how one’s inference concerning an outcome of interest varies as a function of the magnitude of non-identifiable selection bias.
Ten Simple Rules for a Computational Biologist's Laboratory Notebook.

One of the major hurdles I face as the head of a computational biology laboratory is convincing my research team—particularly those pursuing exclusively mathematical and computational modeling—that they need to keep a laboratory notebook. There seems to be a misconception in the computational biology community that a lab notebook is only useful for recording experimental protocols and their results. A lab notebook is much more than that. It is an organizational tool and memory aid, which serves as the primary record of scientific research and activity for all scientists. It also serves as a legal record of ownership of the ideas and results obtained by a scientist. Here, I present the best practices (summarized as ten rules) for keeping a lab notebook in computational biology, for scientists pursuing exclusively “dry” research.
Prostaglandin E2 receptor subtype 2 (EP2) null mice are protected against murine lung tumorigenesis

Background: Manipulating prostaglandin (PG) production modulates tumor development. Elevated PGI2 production prevents murine lung cancer, while decreasing PGE2 content protects against colon cancer. PGE2 receptor subtype 2 (EP2)-deficient mice were hypothesized to be resistant to lung tumorigenesis. Materials and Methods: EP2 null BALB/c mice and their wild-type littermates were exposed to an initiation- promotion carcinogenesis protocol and lung tumorigenesis was examined. Chronic lung inflammation was induced to determine whether EP2 ablation influenced inflammatory cell infiltration. Results: Tumor multiplicity in EP2 null mice was 34% lower than in their wild-type littermates (21.9±3.0 vs. 14.5±2.9 tumors/mouse, p<0.001). The lung tumor burden, an indicator of growth rate, also declined (57%, p<0.05). All the mice exhibited similar inflammatory cell infiltration. Conclusion: PGE2, acting through EP2, enhanced lung tumorigenesis through a mechanism that may be distinct from its pro- inflammatory activity. Thus, EP2 is a potential target for novel chemoprevention strategies. Lung cancer is the leading cause of cancer death in the United States, and the majority of lung cancers are diagnosed in former smokers (1). The large number of current and former smokers, coupled with poor 5-year survival rates, emphasizes the need for effective chemopreventive agents. Prostaglandins are lipid mediators derived from arachidonic acid by the action of cyclooxygenase (COX) enzymes and are important in cancer biology. The need for better lung cancer chemopreventive strategies beyond smoking cessation, coupled with the impressive reduction in colon cancer observed with cyclooxygenase (COX) inhibition, has stimulated considerable interest in manipulating the pulmonary prostaglandin content to modify lung cancer risk. Prostaglandin E2 (PGE2) mediates several hallmarks of
High-frequency subband compressed sensing MRI using quadruplet sampling.

Purpose To present and validate a new method that formalizes a direct link between k-space and wavelet domains to apply separate undersampling and reconstruction for high- and low-spatial-frequency k-space data. Theory and Methods High- and low-spatial-frequency regions are defined in k-space based on the separation of wavelet subbands, and the conventional compressed sensing problem is transformed into one of localized k-space estimation. To better exploit wavelet-domain sparsity, compressed sensing can be used for high-spatial-frequency regions, whereas parallel imaging can be used for low-spatial-frequency regions. Fourier undersampling is also customized to better accommodate each reconstruction method: random undersampling for compressed sensing and regular undersampling for parallel imaging. Results Examples using the proposed method demonstrate successful reconstruction of both low-spatial-frequency content and fine structures in high-resolution three-dimensional breast imaging with a net acceleration of 11–12. Conclusion The proposed method improves the reconstruction accuracy of high-spatial-frequency signal content and avoids incoherent artifacts in low-spatial-frequency regions. This new formulation also reduces the reconstruction time due to the smaller problem size. Magn Reson Med 70:1306–1318, 2013. © 2012 Wiley Periodicals, Inc.
Binding two-loop vacuum-polarization corrections to the bound-electron g factor

We commence the evaluation of the one- and two-loop binding corrections to the $g$ factor for an electron in a hydrogenlike system of order ${\ensuremath{\alpha}}^{2}{(Z\ensuremath{\alpha})}^{5}$ and consider diagrams with closed fermion loops. The one-loop vacuum-polarization correction is rederived and confirmed. For the two-loop vacuum-polarization correction, due to a specific gauge-invariant set of diagrams with closed fermion loops, we find a correction $\ensuremath{\delta}g=7.442{(\ensuremath{\alpha}/\ensuremath{\pi})}^{2}{(Z\ensuremath{\alpha})}^{5}$. Based on the numerical trend of the coefficients inferred from the gauge-invariant subset, we obtain a numerically large tentative estimate for the complete two-loop binding correction to the $g$ factor (sum of self-energy and vacuum polarization).
A review of wetlands remote sensing and defining new considerations

Significant progress has been made in using remote sensing as a means of acquiring information about wetlands. This research provides a brief review of selected previous works, which address the issues of wetland identification, classification, biomass measurement, and change detection. Suggested new research emphases include compiling basic spectral‐reflectance characteristics for individual wetland species by means of close‐range instrumentation, analyzing canopies architectures to facilitate species identification, and assessing the impact on composite spectral signatures of wet soils and variable depths of standing water beneath emergent canopies. These research foci are justifiable when considered in the context of environmental change / variability and the production of trace gases.
Rat heart pyrophosphate phosphohydrolase activities. Sub-cellular distribution, catalytic properties, and hormonal responses

Abstract 1. 1. Inorganic pyrophosphate metabolism in cardiac tissue homogenates has been investigated. 2. 2. A sub-cellular distribution study indicated that the predominant PP i -metabolizing activity is Mg 2+ -stimulated soluble-fraction phosphohydrolase which is maximally active in the range pH 7–7.5. 3. 3. Relatively small amounts of activity also were detected in particulate fractions at pH 7.3 in the presence of Mg 2+ . Activity was essentially absent from all fractions at pH 5.6 without added Mg 2+ . 4. 4. PP i -glucose phosphotransferase activity 1 could not be detected in any sub-cellular fraction or in homogenates. 5. 5. Catalytically, the soluble fraction activity resembles a number of other PP i phosphohydrolases with respect to (a) absolute requirement for Mg 2+ , (b) alkaline pH optimum (pH 7.3 for the heart enzyme), and (c) marked sensitivity to Ca 2+ inhibition. 6. 6. Alloxan diabetes produced an approx. 33% drop in PP i phosphohydrolase activity. Insulin administration, adrenalectomy, or cortisone treatment did not produce statistically significant changes in levels of enzymic activity. 7. 7. Inhibition due to Ca 2+ was reversed by EDTA or additional Mg 2+ , but not by supplemental PP i . Citrate inhibited the system both in the presence and absence of Ca 2+ . 8. 8. A feedback mechanism for retardation of calcification in the vascular system of and near the heart is suggested based on the observations that (a) heart PP i phosphohydrolase is extremely sensitive to Ca 2+ inhibition, and (b) calcification of the aorta is inhibited by PP i (ref. 2).
Computational complexity of fixed points and intersection points

Abstract We study the computational complexity of Brouwer′s fixed point theorem and the intersection point theorem in the two-dimensional case. Papadimitriou (1990, in "Proceedings, 31st IEEE Sympos. Found. Comput. Sci.," pp. 794-801) defined a complexity class PDLF to characterize the complexity of the fixed point theorem in the three-dimensional case. We define a subclass PMLF of PDLF and show that the fixed points and the intersection points of polynomial-time computable functions are not polynomial-time computable if PMLF contains a function on unary inputs that is not polynomial-time computable.
Complexity reduction on two-dimensional convolutions for image processing

Presented here is a method for reducing the computational complexity of two-dimensional linear convolutions used in image processing like binary image scaling. This method is a hybrid of convolving at run-time and convolving by table lookup. The convolution step in image processing usually calculates a weighted average of an area of the input image by calculating the entry-by-entry multiplication of the input pixels with a weight table. This method partitions the calculations in the convolution step and stores pre-calculated partial results in lookup tables. When the convolution step takes place, a binary indexing is used to retrieve the partial results and the final result is obtained by summing up the partial results. A line cache and a double buffering scheme are designed to reduce memory access in table lookup. Space and time complexities are analyzed and compared to the conventional two-dimensional linear convolutions. We demonstrate that an order of magnitude reduction in the computational cost can be achieved. Examples, test images and performance data are provided.
Magnetic Properties of Erbium Metal

Measurements of the magnetic moment of erbium metal in the temperature range from 20.4\ifmmode^\circ\else\textdegree\fi{}K to 90\ifmmode^\circ\else\textdegree\fi{}K are reported. The initial susceptibility shows a maximum at 78\ifmmode^\circ\else\textdegree\fi{}K and the metal appears to become ferromagnetic near 20\ifmmode^\circ\else\textdegree\fi{}K.
Quarkonia and heavy-quark relaxation times in the quark-gluon plasma

A thermodynamic T-matrix approach for elastic two-body interactions is employed to calculate spectral functions of open and hidden heavy-quark systems in the quark-gluon plasma. This enables the evaluation of quarkonium bound-state properties and heavy-quark diffusion on a common basis and thus to obtain mutual constraints. The two-body interaction kernel is approximated within a potential picture for spacelike momentum transfers. An effective field-theoretical model combining color-Coulomb and confining terms is implemented with relativistic corrections and for different color channels. Four pertinent model parameters, characterizing the coupling strengths and screening, are adjusted to reproduce the color-average heavy-quark free energy as computed in thermal lattice QCD. The approach is tested against vacuum spectroscopy in the open (D, B) and hidden ({Psi} and {Upsilon}) flavor sectors, as well as in the high-energy limit of elastic perturbative QCD scattering. Theoretical uncertainties in the static reduction scheme of the four-dimensional Bethe-Salpeter equation are elucidated. The quarkonium spectral functions are used to calculate Euclidean correlators which are discussed in light of lattice QCD results, while heavy-quark relaxation rates and diffusion coefficients are extracted utilizing a Fokker-Planck equation.
Semen analysis in adolescent cancer patients prior to bone marrow transplantation: when is it too late for fertility preservation?

available at http://jurology.com/ Editorial Comment: It may be difficult to cryopreserve sperm in young men with hematological malignancies but bone marrow transplantation makes it impossible. This article is yet another reminder that we must urge our oncologic colleagues to offer sperm cryopreservation as soon as possible to all adolescents undergoing cancer therapy. Saving the life of a young man is good. Saving the life of a potential father is even better. Abstract available at http://jurology.com/ Editorial Comment: These investigators observed that direct incubation of mouse sperm with vasopressin impaired sperm function, including motility and fertilization. While a dose dependent response was identified, all doses were inhibitory. The scientific implications are intriguing and merit further inquiry. The clinical implications are concerning. Just how much vasopressin may be bioavailable and harm sperm in the human testis and reproductive tract?
PREPARATION OF ULTRA SMALL SAMPLES FOR OPTICAL AND MICROPROBE ANALYSIS

This paper describes a simple but satisfactory new method for the preparation of tiny, varied and specialized specimens for electron or ion-microprobe analysis developed over the past five years. Microtektites, individual chondrules, single grains, blebs from lunar samples and meteoritic minerals have been prepared by this technique. A description of the preparation of these usually difficult samples from the initial mounting through the various polishing steps to their final polish is presented in detail. The procedures used to prevent any contamination of these specimens by the polishing agents and to prevent cross contamination to the other samples used for geochronology studies are presented.
Pre-aortic left renal vein compression syndrome (Magoss and Walshe syndrome)

A case of a pre-aortic left renal vein compression by the aorta is reported. The clinical presentation was characterized by the left flank pain varying with body position. Renal venography was crucial for the diagnosis of this lesion. The left renal vein was successfully decompressed by ovarian vein-vena cava shunt surgery. The patient's left flank pain subsided after the surgery. This is the first reported case of a left renal vein compression syndrome by the aorta following the nephrotic syndrome.
Antisense oligodeoxynucleotides as a tool in developmental neuroendocrinology.

Antisense oligodeoxynucleotides have been highly successful agents at modulating gene expression in the adult brain and widely exploited in the field of neuroendocrinology. We have also used this technique in the developing brain to explore the role of select proteins during sensitive periods of development, particularly those influenced by steroid hormones. Presented here are the technical details of using antisense oligodeoxynucleotides in the neonatal brain, as well as a review of some of our successes and failures. Our goal is to illustrate the relative ease of use of this technique in neonates and demonstrate the power such an approach offers so that other investigators will also begin to take advantage of this useful tool.
Transcriptional arrest of yeast RNA polymerase II by Escherichia coli rho protein in vitro.

Abstract A promoter-independent assay utilizing poly(dC)-tailed DNA templates has revealed that Saccharomyces cerevisiae whole-cell extracts can be proficient for transcription by the endogenous yeast RNA polymerase II as well as for correct 3'-end RNA processing. Our attempts to examine the fate of polymerase II itself were inconclusive, because only trace transcription products corresponded to the expected size of terminated RNA species. Transcription in our processing-proficient extract was thus insufficient to cause termination. To test our system with a known, albeit heterologous, signal, we examined a dC-tailed template carrying the E. coli rho-dependent termination signal trp t' in the yeast extract. Transcripts from this template were not susceptible to processing, but addition of rho protein resulted in two distinct truncated transcripts that could not be chased by excess unlabeled nucleotides. These RNA species thus represented stably paused or terminated polymerase II products, and their absence when a mutated unresponsive trp t' template was used affirmed that they were due to the effects of rho. E. coli RNA polymerase added to a yeast extract pretreated with alpha-amanitin was also halted by rho at these same two sites. A mutated rho protein, while only partly defective with E. coli polymerase, failed to provoke arrest when transcription was carried out by RNA polymerase II. Thus, functional rho and its cognate site, trp t', appear necessary and sufficient to elicit the production of truncated transcripts by RNA polymerase II in a yeast whole-cell extract. The ability of rho to halt the eukaryotic enzyme strengthens the likelihood that a rho-like helicase may be involved in RNA polymerase II transcription termination.
Decreased hepatic insulin extraction precedes overt noninsulin dependent (Type II) diabetes in obese monkeys.

Many obese middle-aged rhesus monkeys (Macaca mulatta) spontaneously develop noninsulin dependent diabetes mellitus (NIDDM). Basal hyperinsulinemia and increased stimulated plasma insulin levels are associated with this obesity and precede the onset of overt diabetes. The present studies sought to determine the relative contributions of enhanced insulin secretion and of reduced insulin clearance to this early obesity-associated hyperinsulinemia. Direct simultaneous measurement of portal and jugular vein insulin levels in two normal monkeys showed a constant rate of hepatic insulin extraction of 56±3% over the range of peripheral insulin levels from 351±113 to 625±118 pmol/L. In 33 additional monkeys ranging from normal to diabetic, basal C-peptide levels were examined as an indicator of β-cell secretion and the molar ratio of plasma C-peptide to insulin (C/I ratio) under basal steady state conditions calculated as an index of hepatic insulin extraction. Well in advance of overt diabetes, there was a progressive decline of 67% in the apparent hepatic insulin extraction rate in association with increased obesity and plasma insulin levels. Basal insulin levels and hepatic insulin extraction returned toward normal in monkeys with impaired glucose tolerance and in those with overt diabetes. We conclude that reduced insulin disposal, probably due to reduced hepatic extraction of insulin, in addition to increased β-cell activity, contributes to the development of basal hyperinsulinemia in obese rhesus monkeys progressing toward NIDDM. In addition, in overt diabetes, normal hepatic insulin extraction in the presence of limited β-cell secretion may exacerbate the hypoinsulinemic state. (OBESITY RESEARCH 1993; 1:252–260)
Resolution of racemic substances by liquid ion-exchange

Abstract Two optically active liquid anion-exchangers have been synthesized. The separation factors of the enantiomers of sodium (±)-mandelate and sodium- N -acetyl-(±)-alanate have been determined by batchwise equilibration of aqueous solutions of the salts with chloroform solutions of each of the exchangers. Sodium mandelate has been resolved by Craig countercurrent extraction with one of these exchangers. Optically pure products can be obtained even though the liquid ion-exchanger is not optically pure.
A kernel for high-performance multicast communications

A kernel is described, called the link kernel, for high-performance interprocess communication among shared-memory multiprocessors using an Ethernet. The link kernel provides asynchronous multicast communication service without protocol overhead. Links are created by listeners, and processes may be simultaneously talkers and listeners. Processes access links through a global link table. Multicast addresses are site-independent, so communication is independent of process locations in the network. Communication is asynchronous, so much of the overhead of message management is masked by parallel computation. >
A model of the visual localization of prey by frog and toad

In this paper we demonstrate how prey localization can be acheived rapidly and accurately by coupling prey-selection and lens-accommodation processes within a feedback loop. Information derived from prey selection supplies a setpoint for accomodation. In turn, adjustment of the lens modifies the visual input and can alter the prey selection process. The natural feedback of this goal-seeking system automatically corrects for the problem of ambiguity in binocular matching. Although it is of general interest as a depth algorithm, we tie the model to the known anatomy, physiology and behavior of frogs and toads. Instead of building a global depth-map we propose that the goal of catching a prey leads a frog or toad to select a particular region of its visual world for special scrutiny. We suggest that the first step of the prey-catching sequence is to adjust the accommodative state of the lenses and thus lock the visual apparatus on to a stimulus. We identify brain regions that could provide the neural substrates necessary to support the model's various functional stages and present experiments, with a computer simulation, that compare its functioning to animal behavior.
Oxydehydrogenation of propane over Mg-V-Sb-oxide catalysts. II. Reaction kinetics and mechanism

Recently we reported that Mg4V2Sb2Ox is selective for propane andn-butane Oxydehydrogenation at low hydrocarbon conversion, and that propane is oxidized in parallel reactions to propylene and COx. We report now on the kinetics of propane and propylene oxidations over this catalyst. The partial oxidations of propane and propylene and zero-order in oxygen, whereas deep oxidations of both hydrocarbons are half-order. This difference in reaction order indicates that different forms of reactive oxygen are involved in the partial and deep oxidation reactions. Presumably, nucleophilic lattice oxygen partakes in the partial oxidation, while electrophilic dissociatively adsorbed oxygen is involved in deep oxidation. A single activated surface adsorbed state of the hydrocarbons is thought to be involved in both the partial and deep oxidation reactions. An interpretation of the observed reaction kinetics in context of the Mg4V2Sb2Ox solid state chemistry, and the partial oxidation literature in general, suggests that selective oxydehydrogenation of propane occurs on isolated (Sb-O-V-O-Sb) sites, deep oxidation on multiple vicinal vanadium sites (Sb-O-V-O-V-O-Sb), and partial oxidation of propylene to acrolein on subsurface V-promoted antimony sites (Sb-O-Sb). Therefore, unproved selectivity of desired intermediates (propylene/acrolein) should be achieved by further lowering the vanadium concentration and/or through key solid state positioning of the vanadium in the catalyst lattice. Alternatively, selective doping to electronically decrease the electrophilicity of the waste forming sites and its appended oxygen should also help depress the waste forming reaction channels in favor of the desired partial oxidation channels. Finally it is anticipated that higher useful product yields would be attained with a compositionally optimized Mg-V-Sb-oxide catalyst by opting for a more stable, isolatable intermediate, e.g., acrylonitrile, by reacting propane in the presence of ammonia and oxygen (air) over this catalyst.