cssi/SciSciGPT-SciSciNet huggingface dataset:
Europa Lander Engine Plume Interactions with the Surface and Vehicle

NASA's proposed Europa Lander Project would deliver an autonomous robotic lander with a suite of scientific equipment to the icy moon's surface in order to excavate surface samples and search for bio-signatures. This mission concept would land on the Europan surface using JPL's iconic Sky Crane technique, by which a powered descent vehicle is propelled and maneuvered into a hovering position with eight monopropellant hydrazine engines before lowering its lander.[1] The gas plumes of these engines would expand rapidly into Europa's near-vacuum surface conditions and impinge upon the moon's surface, the lander, and descent vehicle to potentially detrimental effect. Engine plumes induce torques and heating of spacecraft and can transport gas and liquid propellant byproducts to contaminate sensitive instrument surfaces, impacting science collection. [1]–[6] Major interactions of concern include surface contamination with, and subsurface penetration of, propellant byproducts; the removal and transport of particulates from plume-induced pressure gradients; and the sublimation of surface ices. Therefore it is critical to understand and characterize the proposed Europa Lander's engine plumes. Landings onto Europa and other airless bodies - i.e. those without collisional atmospheres, a class including Enceladus, Earth's moon, and many asteroids - will generate engine plume flow-fields that transition through continuum, rarefied gas-dynamic, and free-molecular regimes. Such complex, non-equilibrium flow-fields require hybrid solution schemes. A one-way-coupled continuum-to-rarefied hybrid scheme has been demonstrated, validated, and deployed for the simulation of single-engine, steady-state lander plumes impinging onto both the Earth's moon and Europa in a multidisciplinary effort at JPL.[2] The present work extends that hybrid framework to model the complex interactions of the full set of four Europa Lander descent engine plumes, each canted at 30°, generated during the final Sky Crane bridled descent. We report resultant surface pressure, heating, and contaminant depositions, and we demonstrate a framework that can be applied to model realistically-rough Europa-like surface morphologies. Likewise, we report the pressures, heat fluxes, and contaminant depositions induced by transient descent engine plumes onto both the Europa Lander and descent vehicle envelopes during landing, and we propose and outline several detailed campaigns of future work to the benefit of Europa Lander's engineering and science teams.
A near-infrared frequency comb for Y+J band astronomical spectroscopy

Radial velocity (RV) surveys supported by high precision wavelength references (notably ThAr lamps and I2 cells) have successfully identified hundreds of exoplanets; however, as the search for exoplanets moves to cooler, lower mass stars, the optimum wave band for observation for these objects moves into the near infrared (NIR) and new wavelength standards are required. To address this need we are following up our successful deployment of an H band(1.45-1.7μm) laser frequency comb based wavelength reference with a comb working in the Y and J bands (0.98-1.3μm). This comb will be optimized for use with a 50,000 resolution NIR spectrograph such as the Penn State Habitable Zone Planet Finder. We present design and performance details of the current Y+J band comb.
Echocardiographic predictors of new-onset atrial arrhythmias in patients undergoing hematopoietic stem cell transplantation.

Abstract Background Atrial arrhythmias following hematopoietic stem cell transplantation (HSCT) have been associated with increased length of stay, need for intensive care, and increased mortality within one-year post-transplant. We sought to identify echocardiographic parameters that may predict the development of new atrial arrhythmias post-HSCT. Methods We performed a retrospective chart review of 753 consecutive patients who underwent HSCT at the University of Chicago from January 2015 through December 2019. Patients with baseline echocardiogram within 6 months prior to transplantation were included. Those with prior transplants, history of atrial arrhythmias, or unavailable echocardiographic images were excluded, resulting in 187 patients included for final analysis. Baseline clinical and demographic variables, as well as echocardiographic parameters, were compared between patients who developed new atrial arrhythmias post-HSCT versus those who did not. Results Of the 187 patients included for analysis, 25 (13%) developed new atrial arrhythmias, with 13 of these occurring within 30 days of transplantation. Despite no significant difference in left atrial (LA) end-systolic volume between those with and without new arrhythmia following HSCT (OR 1.04; 95% CI 0.91–1.09, p = 0.233), univariable analysis demonstrated that patients who developed atrial arrhythmias had reduced LA function, as reflected by lower LA emptying fraction (OR 0.94; 95% CI 0.91–0.98, p = 0.003) and lower LA reservoir strain (OR 0.95; 95% CI 0.92–0.99, p = 0.009). Conclusions Echocardiographic indices of LA function, namely LA emptying fraction and LA reservoir strain, can identify patients at risk for developing new atrial arrhythmias post-HSCT, prior to the development of morphologic changes in the LA.
Prognostic histopathologic features of canine glial tumors

Gliomas are relatively common tumors in aged dogs (especially brachycephalic breeds), and the dog is proving to be useful as a translational model for humans with brain tumors. Hitherto, there is relatively little prognostic data for canine gliomas and none on outcome related to specific histological features. Histologic sections of tumor biopsies from 33 dogs with glioma treated with surgical resection and immunotherapy and 21 whole brains obtained postmortem were reviewed. Tumors were diagnosed as astrocytic, oligodendroglial, or undefined glioma using Comparative Brain Tumor Consortium criteria. Putative features of malignancy were evaluated, namely, mitotic counts, glomeruloid vascularization, and necrosis. For biopsies, dogs with astrocytic tumors lived longer than those with oligodendroglial or undefined tumor types (median survival 743, 205, and 144 days, respectively). Dogs with low-grade gliomas lived longer than those with high-grade gliomas (median survival 734 and 194 days, respectively). Based on analysis of tumor biopsies, low mitotic counts, absence of glomeruloid vascularization, and absence of necrosis correlated with increased survival (median 293, 223, and 220 days, respectively), whereas high mitotic counts, glomeruloid vascularization, and necrosis correlated with poor survival (median 190, 170, and 154 days, respectively). Mitotic count was the only histological feature in biopsy samples that significantly correlated with survival (P < .05). Whole-brain analyses for those same histologic features had similar and more robust correlations, and were statistically significant for all features (P < .05). The small size of biopsy samples may explain differences between biopsy and whole-brain tumor data. These findings will allow more accurate prognosis for gliomas.
Managing environmental change through inter-agency collaboration: Protective governance in mandated sustainability planning

Abstract When organizations must collaborate to address resource sustainability dilemmas, concerns about the risk of losing autonomy can dissuade them from joining formal collaborative institutions. We argue that governing rules designed to protect autonomy can entice participation from diverse stakeholders, including underprivileged and often marginalized environmental actors, while enhancing confidence in the collaboration’s ongoing and anticipated sustainability efforts. We test this argument in the context of large-scale governance reform in the state of California, which recently mandated local governing entities to collaborate for sustainable groundwater planning or risk state intervention. Using data collected from both archival records and a statewide survey of local groundwater managers, the analysis shows that inclusive representation, unweighted voting power structures, and unanimity decision rules constitute protective governance, which in turn boosts participating agencies’ confidence in sustainability efforts. This study provides theoretical and empirical insights into how organizations can address constitutional issues to improve collaborative processes and outcomes of environmental sustainability efforts.
Ultra low PMD fibers by fiber spinning

This paper reviews fiber spinning technology for making low PMD fibers. Theoretical understanding of fiber spinning mechanism and features of spun fibers, as well as applications in fiber spin profile designs are discussed.
Optimum filtering for maximum channel capacity in PSK and FSK modulation systems

A general FSK spectrum simulator is written in MATLAB(R) to evaluate the optimum filtering for FSK modulation systems in near-far interference limited channels. In addition, only constant envelope (CE) signals are considered because of their demonstrated energy efficiency. The Fourier Uncertainty Relation is used to evaluate the relative performance of partial response filtering to M-ary signaling. Simulation results are compared with hardware measurement. A similar program is in process for CE-PSK modulation.
Assessing denitrification in groundwater using natural gradient tracer tests with 15N: In situ measurement of a sequential multistep reaction

[1] Denitrification was measured within a nitrate-contaminated aquifer on Cape Cod, Massachusetts, using natural gradient tracer tests with 15N nitrate. The aquifer contained zones of relatively high concentrations of nitrite (up to 77 μM) and nitrous oxide (up to 143 μM) and has been the site of previous studies examining ground water denitrification using the acetylene block technique. Small-scale (15–24 m travel distance) tracer tests were conducted by injecting 15N nitrate and bromide as tracers into a depth interval that contained nitrate, nitrite, nitrous oxide, and excess nitrogen gas. The timing of the bromide breakthrough curves at down-gradient wells matched peaks in 15N abundance above background for nitrate, nitrite, nitrous oxide, and nitrogen gas after more than 40 days of travel. Results were simulated with a one-dimensional transport model using linked reaction kinetics for the individual steps of the denitrification reaction pathway. It was necessary to include within the model spatial variations in background concentrations of all nitrogen oxide species. The model indicated that nitrite production (0.036–0.047 μmol N (L aquifer)−1 d−1) was faster than the subsequent denitrification steps (0.013–0.016 μmol N (L aquifer)−1 d−1 for nitrous oxide and 0.013–0.020 μmol N (L aquifer)−1 d−1 for nitrogen gas) and that the total rate of reaction was slower than indicated by both acetylene block tracer tests and laboratory incubations. The rate of nitrate removal by denitrification was much slower than the rate of transport, indicating that nitrate would migrate several kilometers down-gradient before being completely consumed.
Extending virtual humans to support team training in virtual reality

This chapter describes the use of virtual humans and distributed virtual reality to support team training, where students must learn their individual role in the team as well as how to coordinate their actions with their teammates. Students, instructors, and virtual humans cohabit a 3D, interactive simulated mock-up of their work environment, where they can practice together in realistic situations. The virtual humans can serve as instructors for individual students, and they can substitute for missing team members, allowing students to practice team tasks when some or all human instructors and teammates are unavailable. The chapter describes our learning environment, the issues that arise in developing virtual humans for team training, and our design for the virtual humans, which is an extension of our Steve agent previously used for one-on-one tutoring.
Evaluation of the Selection and Training of Fighter Pilots

References Hess, J. R. and Shirk, F. J., "Summary of Results of aPolysonic Wind Tunnel Test of a 5% Scale Model F-4E with Operable Canards," McDonnell Douglas Rept. MDC A0918, Feb. 1971, McDonnell Douglas Corp., St. Louis, Mo. Kisslinger, R. L. and Vetsch, G. J., "Survivable Flight Control System Interim Report No. 1, Studies, Analyses and Approach, Supplement for Control Law Development Studies," AFFDLTR-71-20, Supplement 2, May 1971, Air Force Flight Dynamics Laboratory, Wright-Patterson Air Force Base, Ohio.
Optical simulation of phase-distorted imaging systems: nonlinear and adaptive optics approach

We discuss a technique based on nonlinear and adaptive optics for simulation of phase-distortion effects in imaging systems. This technique uses a nonlinear two-dimensional optical feedback system to produce a controllable spatially and temporally varying chaotic intensity distribution. The intensity pattern is converted into a spatially varying thin phase screen using an optically addressed spatial phase modulator. A chaotic phase distortion is then introduced into an imaging system's output image by propagation through the phase screen. A deformable mirror with computer control is used for simulation of large-scale phase distortions.
Signature analyzers in built-in self-test circuits: a perspective

The test response compression technique using signature analyzers or linear feedback shift registers (LFSRs) is discussed and some representative built-in self-test (BIST) designs which make use of LFSRs are presented. Signature analysis is a compression technique based on the concept of cyclic redundancy checking (CRC) and realized in hardware using LFSRs. The input to the LFSR is received from the output of a multiple input single output circuit under test (CUT). The structure and characteristics of LFSRs including a simplified mathematical analysis showing the confidence level in detecting faults are discussed. Some BIST design examples which include a programmable logic array, semiconductor memory, and a microcomputer are presented. >
Editorial - can distance learning improve the quality of medical education?

A search of the literature has revealed that the effectiveness of distance learning for medical students, residents, and physicians is not well tested or understood even though the revolution in technology and the advancement of the internet have made distance learning feasible and widely available. In 1995, Houston and Beck1 distributed an educational package related to eye diseases to 270 general practitioners and evaluated the improvement in their knowledge of 6 common eye diseases that general practitioners most often see in their practices. The authors found that the distance learning effort led to improvement in theoretical patient management. Stout et al2 performed a study that included 36 physicians, nurses, and medical assistants from 14 primary care pediatric practices. The authors tested the effectiveness of a multifaceted distance learning approach in improving spirometry training and knowledge. They used the Spirometry Fundamentals CD-ROM, case-based interactive webinars led by clinical experts, and internet-based spirometry training. The authors concluded that their program led to an increase in the quality of spirometry testing and improved assessment of asthma severity levels. Distance learning modules can also be conducted as a part of larger quality improvement programs. A recent study carried out in Dutch hospitals described the use of an e-learning course to educate nurses about delirium and its care within a larger quality improvement initiative. The authors concluded that in many healthcare organizations e-learning is an effective way to educate large groups of professionals.3 Distance learning has many advantages. McGrath4 stated that distance learning allows the learner to be in charge of the environment and time of learning. Distance learning programs may be more convenient for many health professionals because learners can fit the learning activity within their busy schedules. Static media that remain available to the learner also facilitate review of the educational material as desired. However, distance learning tools and strategies have some limitations. They can be expensive or difficult to implement and may create a feeling of isolation and insecurity in learners who are accustomed to live, in-person education activities. More research is needed to assess the efficacy of distance learning in improving the quality of medical education and to identify the circumstances and strategies that are most effective for specific individuals and learning organizations. Distance learning can be a powerful tool for improving the quality of medical education, which is an important factor in enhancing the quality of healthcare delivery.
The influence of multiple slip systems on the brittle–ductile transition in silicon

Abstract The brittle–ductile transition results from the competition between cleavage fracture and dislocation activities at or near the crack tip. In the present paper a 2-dimensional dynamic dislocation simulation is performed. The material properties used in the simulation are those of single crystalline silicon. Dislocations are assumed to emit from an atomically sharp cleavage crack along different symmetrically placed slip systems. Individual dislocations move away from the crack tip following an Arrhenius law driven by the net resolved shear stress. The dislocations shield the crack tip from the increasing far field stress intensity. Brittle fracture occurs when the crack tip stress intensity reaches the intrinsic fracture toughness. Ductile failure is assumed to occur if the far field stress intensity reaches a critical value significantly higher than the intrinsic toughness. The study focuses on the influence of interaction forces between dislocations in different slip systems. With all interactions fully accounted for, the simulations show that the activation of multiple slip systems results in a sharp transition whereas the activation of a single symmetric pair results in a gradual transition.
Surgical management of benign parotid disease

Abstract The pertinent surgical anatomy of the parotid gland is reviewed. Benign parotid diseases, which may require surgical therapy, are classified and described and the treatment is suggested. Some of the aspects of conservative parotidectomy and the complications that may arise from such parotidectomy are discussed.
Idiopathic hypoparathyroidism and chronic adrenal insufficiency: a case report.

THE clinical syndrome of idiopathic hypoparathyroidism has recently been reviewed by Steinberg and Waldron (1). They accept the criteria previously established by Drake and associates (2)—low serum calcium level, high serum phosphate level, normal renal function, normal bones by x-ray examination, and chronic tetany—but make several minor modifications. These include the requirement that the serum phosphorus level be above 5 mg. per 100 ml. in adults and above 7 mg. per 100 ml. in persons under the age of 16, and that the clinical course be not characterized by chronic diarrhea. The coincidence of idiopathic hypoparathyroidism and chronic adrenal insufficiency (Addison's disease) has been reported in 3 previous cases to our knowledge. Only 1 of these;, however, (that reported by Leonard (3) in 1946) would seem to have been sufficiently documented to make both diagnoses certain. The foregoing criteria for the diagnosis of idiopathic hypoparathyroidism were met in this case, and autopsy revealed complete fi...
Programming biological operating systems: genome design, assembly and activation

This Perspective takes the reader through the important steps in bacterial genome assembly and activation and concludes with an outlook on how customized genomes may be achieved.
Transferability of aliphatic isocyanates from recently applied paints to the skin of auto body shop workers.

Isocyanates, the essential cross-linking chemicals used to make polyurethane, are potent sensitizers and a common cause of occupational asthma. In addition, isocyanate (NCO) skin contact may contribute to the development of isocyanate asthma. Prior work has shown that unbound NCO can persist on recently spray coated auto body parts after appearing dry. The purpose of this study was to assess whether isocyanate skin exposure can result from handling such surfaces. Quantitative surface and skin wipe sampling for total NCO was performed on test panels sprayed with aliphatic isocyanate coatings, and on paired skin samples obtained from participants who had rubbed the recently dried surfaces. Surface and skin samples, obtained from 18 workers in five auto body shops, were prepared following NIOSH method 5525 (modified for skin samples), and isocyanate species derived from hexamethylene diisocyanate and isophorone diisocyanate were analyzed using high-performance liquid chromatography with ultraviolet and fluor...
Effects of Endplate and Mechanical Loading on Solute Transport in Intervertebral Disc

The intervertebral disc (IVD) is the largest cartilaginous structure in human body that contributes to flexibility and load support in the spine. To accomplish these functions, the disc has a unique architecture consisting of a centrally-located nucleus pulposus (NP) surrounded superiorly and inferiorly by cartilage endplates (CEP) and peripherally by the annulus fibrosus (AF). Disc degeneration is strongly linked to low back pain. Poor nutrient supply has been suggested as a potential mechanism for disc degeneration. Previous theoretical studies have shown that the distributions of nutrients and metabolites (e.g., oxygen, glucose, and lactate) within the IVD depended on tissue diffusivities, nutrient supply, and cellular metabolic rates [1, 2]. Based on a multiphasic mechano-electrochemical finite element model of human IVD [3], our recent theoretical study suggested that the mechanical loading has little effect on small solute transport (e.g., glucose), but significantly affects large solute transport (e.g., growth factor). The objective of this study was to further develop the multiphasic finite element model of IVD by including the cartilage endplate and considering the nutrient consumption of disc cells. Using this model, the effects of endplate and mechanical loading on solute transport in IVD were examined.Copyright © 2008 by ASME
TU-E-204C-04: New Directions and Clinical Applications of Multicriteria Optimization

We report on the first clinical comparisons (10 patients: 5 brain, 5 pancreas) of IMRT planning with a Pareto surface based multi‐criteria optimization (MCO) system versus a traditional IMRT inverse planning system. For the MCO system, we use the MCO‐IMRT planning module provided by RaySearch Laboratories, and for the traditional planning system we use XiO from CMS. For each patient (5 brain cases, 5 pancreatic cases), the patient is planned and treated with XiO plan as is normally done in our clinic. The planning process was logged however to record treatment planner timing data. The planners were not given any special instructions regarding beam angle selection or optimization formulation, in an attempt to accurately capture the process as done day‐to‐day in our clinic. In parallel, the patients were planned in the MCO system using a template based recipe. Specifically, all patients were planned with 7 equi‐spaced beams (starting from an anterior/posterior beam) and using a pre‐defined set of dosimetric optimization objective functions and constraints (we will discuss these templates as well as provide general guidelines for setting up MCO problems). Once the MCO database was computed (an MCO database is a set of Pareto optimal plans that allows the user to navigate through treatment plan possibility space and select the most desirable tradeoff), the physician navigated to the desired plan. The MCO process was also logged. MCO planning is shown to be far faster than traditional planning, and the reason for this is that the tradeoff decisions are much simpler in the Pareto surface navigation approach. Planning time totaled approximately 15 minutes in the MCO compared with about 2–3 hours for the standard treatment planning. MCO dose distributions were almost always preferred over XiO dose distributions, and otherwise they were considered neither better nor worse. This study provides strong support of the MCO‐based approach for IMRTtreatment planning, both in terms of plan quality and treatment planning efficiency. Given the above positive results, we speculate that MCO‐based treatment planning will become much more popular over the coming years, and will find its way into proton planning and advanced photon techniques such as VMAT. We will review some future topics including comparing modalities (or beam configurations) with multiple Pareto surfaces, robust MCO for IMPT, and VMAT MCO. Learning Objectives: 1. Understand the workflow and formulation differences between standard IMRTtreatment planning and Pareto‐surface based planning. 2. Understand how MCO might be used in tomorrow's clinics, and what work needs to be done to make this a reality.
Experimental Characterization of Piezoelectric Friction Dampers

A piezoelectric friction damper was designed and fabricated to control the 1/4-scale, three-story frame structure in the Structures Laboratory at the University of Missouri-Rolla. In this paper, the damper is characterized in terms of energy dissipation, frequency and temperature dependence, and long-term durability under harmonic loading.
Impact of agitated drying on the powder properties of an active pharmaceutical ingredient

In this study, the impact of agitated drying on the physical and bulk powder properties of an active pharmaceutical ingredient (API) is presented. The effects of different agitated drying conditions such as agitation rate, drying temperature, drying time pre-agitation, drying time during agitation and number of solvent wash cycles on the bulk density, millability, flow and specific surface area is reported. The crystal morphology is altered from fibrous needles to agglomerates when switching from tray to agitated drying. An increase in bulk density and specific surface area was evident when using agitated drying compared to tray drying as hard coarse granules were produced with an increase in the number of fine particles < 10 μm. The bulk density was found to increase with an increase in agitation speed, drying time and number of solvent wash cycles used during filtration. Controlling both fine and coarse particle size of the granules for this API during agitated drying was difficult to achieve due to the fibrous crystal habit. However, the increase in the bulk density observed has the potential to facilitate improvements in the ease of drug product development. In the case of this system further particle size control was required through the use of dry milling.
Quantum-mechanical computers and uncomputability

The time evolution operator for any quantum-mechanical computer is diagonalizable, but to obtain the diagonal decomposition of a program state of the computer is as hard as actually performing the computation corresponding to the program. In particular, if a quantum-mechanical system is capable of universal computation, then the diagonal decomposition of program states is uncomputable. As a result, in a universe in which local variables support universal computation, a quantum-mechanical theory for that universe that supplies its spectrum cannot supply the spectral decomposition of the computational variables. A ``theory of everything'' can be simultaneously correct and fundamentally incomplete.
Inverse Analyses of Transport of Chlorinated Hydrocarbons Subject to Sequential Transformation Reactions

Chemical and biological transformations can significantly affect contaminant transport in the subsurface. To better understand such transformation reactions, an equilibrium-nonequilibrium sorption transport model, HYDRUS-1D, was modified by including inverse solutions for multiple breakthrough curves resulting from the transport of solutes undergoing sequential transformations. The inverse solutions were applied to miscible-displacement experiments involving dissolved concentrations of trichloroethylene (TCE) undergoing reduction and/or transformations in the presence of zero-valent metal porous media (i.e., iron or copper-coated iron filings) to produce ethylene. The inverse model solutions provided a reasonable description of the transport and transformation processes. Simultaneous fitting of multiple breakthrough curves of TCE and ethylene placed additional constraints on the inverse solution and improved the reliability of parameter estimates. Confidence intervals of optimized parameters were reduced significantly in comparison with those obtained by fitting TCE breakthrough curves independently. Further evidence for accurate parameter estimates was given when the parameter values agreed with previously reported values from independent batch and degradation experiments. Optimized values of the normalized degradation rates for the equilibrium (1.4 x 10 -4 to 7.2 x 10 -5 L h -1 m -2 ) and nonequilibrium (1.2 x 10 -4 to 5.5 x 10 -5 L h -1 m -2 ) models compared well with values (0.03 to 6.5 x 10 -5 L h -1 m -2 ) obtained from previous studies. The estimated TCE-iron sorption coefficients (0.52 to 2.85 L kg -1 ) were also consistent with a previously reported value (1.47 L kg -1 ).
Simulation of light scattering in biological tissues : the coherent component

Light propagating in turbid medium can be separated into two parts -- the unattenuated part and the scattered part. The two parts coexist everywhere in the medium and can be described by radiative transport theory. In an optically thick sample of turbid medium, very small portion of the light remain unattenuated and the diffusion model is widely used to describe the propagation of light. Monte Carlo method, having the potential of reaching high accuracy, can be used to account for both parts of the light distribution and has acquired considerable attention lately. We have developed a new method of Monte Carlo simulation and conducted large-scale simulation of converging laser beam propagating through tissue phantoms in slab configurations. In our cases, the unique geometry of the converging laser beams gathers the unattenuated photons together near the focal point and makes it significant even for optically thick samples in comparison with the scattered part. Numerical results were obtained for tissue slabs of different parameters to study the variation of the distribution of the transmitted light. We have also investigated the possibility of characterizing biological tissues through the measurement of unattenuated photons.
Without Consent or Contract: The Rise and Fall of American Slavery

Over the past quarter-century, Robert William Fogel has blazed new trails in scholarship on the lives of the slaves in the American South. Now he presents the dramatic rise and fall of the "peculiar institution," as the abolitionist movement rose into a powerful political force that pulled down a seemingly impregnable system.
Origin of the cystid epidermis during the metamorphosis of three species of gymnolaemate bryozoans

Origin and formation of the body wall epidermis of the ancestrula in three species of gymnolaemate bryozoans were analyzed by scanning and transmission electron microscopy. In the ctenostome Bowerbankia gracilis, the aboral pallial epithelium forms the entire cystid epidermis, whereas in the anascan cheilostome Bugula neritina, the wall and roof regions of the internal sac form the epidermis. In the ascophoran cheilostome Watersipora culcullata, however, both the pallial epithelium and internal sac contribute to the body wall epidermis. In spite of these different origins, the tissues involved in production of the exoskeleton share a common ultrastructure. The various patterns of metamorphosis described here indicate that ancestrular body wall origin may be an important character in the analysis of phylogenetic relationships within the Bryozoa.
Tidal and seasonal variations of sulfate ion in a New Jersey marsh system

Sulfate variations during a tidal cycle were investigated at three sites in a highly polluted tidal marsh. Sulfate- chlorinity relationships were determined in the light of fluctuations in temperature, dissolved oxygen and pH. The relationships were found to be seasonal in nature, being affected by temperature and rainfall effects on biologic productivity. Both reduction of sulfate ion to a sulfide species and oxidation of sulfide species to the sulfate ion were found to occur. Consideration of the sulfide oxidation process suggests the possibility that metals precipitated as sulfides may be mobilized and redistributed in the marsh system.
45nm low-power CMOS SoC technology with aggressive reduction of random variation for SRAM and analog transistors

Mobile system-on-chip (SoC) technologies require high-quality analog active and passive components along with low-power CMOS and dense SRAM. However, area scaling for both the SRAM bit cell and analog CMOS circuits is becoming increasingly difficult due to the impact of transistor random variation. To avoid added cost, co-optimizing the process for low random variation along with high performance and low power is required. We report a 45 nm lowpower technology with significantly reduced random variation for high yielding 0.255 mum2 SRAM arrays and analog transistors. Flexible RF and passive components for mobile SoCpsilas are also described. These process techniques enable continued 50% area scaling at 45 nm and beyond.
Nucleophilic distribution of metallothionein in human tumor cells.

Abstract Metallothionein (MT), a major zinc-binding intracellular protein thiol, has been associated with cytoprotection from heavy metals, antineoplastic drugs, mutagens, and cellular oxidants. Despite its small mass (7 kDa), nuclear partitioning of MT has been observed in both normal and malignant tissues. The factors controlling MT sequestration are unknown. Thus, we examined the regulation of MT subcellular distribution in human cancer cell lines that exhibit prominent nuclear MT. The nuclear disposition of MT was unaltered during cell cycle passage in synchronized cells. MT redistributed to the cytoplasm when cells were exposed to reduced temperature. Cytoplasmic redistribution was also seen in DU-145 and HPC36M prostatic cancer cells after ATP depletion, but not in PC3-MA2 and SCC25/CP cells. Pretreatment with 10 μ M CdCl 2 did not significantly alter MT distribution but did render all cells sensitive to cytoplasmic redistribution after either reduced temperature or ATP depletion. Thus, nuclear retention of MT is energy requiring and this ability of MT to accumulate in subcellular compartments against its concentration gradient may be important in the capacity of MT to supply Zn or other metals to target sites within the cell.
Ultraviolet negative-ion photoelectron spectroscopy of the chromium oxide negative ion

Abstract The photoelectron spectrum of CrO − is reported, with four electron states of CrO detected. The 5 Π ground state of CrO has an electron affinity of 1.221 ± 0.006 eV. An excited 3 Π state is also observed, which lies 8600 ± 40 cm −1 above the ground state. Two additional states of CrO, believed to be triplets, are observed at energies of 4835 ± 80 and 7365 ± 40 cm −1 , respectively.
Fire Suppression in Microgravity: Dynamics of a Polydispersed Water Mist Around an Obstacle

The work presented here aims at characterizing the dynamics of water mist during fire suppression events in cluttered spaces. To this end, a numerical model for a polydispersed water-mist is used. A sectional approach is used to describe the mist behavior. The distributions of the parameters characterizing the mist (size, speed, and direction at injection) are discretized in classes, and they are chosen using a Monte Carlo method. The fate of the droplets in each class is determined by calculating the history of a representative droplet for each class using a Lagrangian approach. The dynamics of the representative droplets and their heat and mass transfer histories are tracked. An extended-film model is used to evaluate droplet evaporation. This mist model interacts in a one-way coupled manner with a pre-calculated flow field around hot obstacles.Copyright © 2004 by ASME
Development and practical utilization of a linear spectrodensitometer

Abstract The development of a linear detector system for the in situ quantitation of thin-layer chromatograms indicates the general applicability of spectrodensitometry, comparable to that of gas-liquid chromatography and liquid column chromatography. There are general requirements to meet, however, regarding chemical methodology and instrumentation, before this technique may be successfully used. A commercially available instrument modified in our laboratories has shown high sensitivity, reliability, versatility, and short analysis times in biological applications and in the monitoring of organic reactions during synthetic work. Statistical calculations indicate that the construction of an automatic linear spectrodensitometer is now feasible. Some predictions appear to be realistic on the basis of the statistical values.
SMART: A Stochastic Multiscale Model for the Analysis of Energy Resources, Technology, and Policy

We address the problem of modeling energy resource allocation, including dispatch, storage, and the long-term investments in new technologies, capturing different sources of uncertainty such as energy from wind, demands, prices, and rainfall. We also wish to model long-term investment decisions in the presence of uncertainty. Accurately modeling the value of all investments, such as wind turbines and solar panels, requires handling fine-grained temporal variability and uncertainty in wind and solar in the presence of storage. We propose a modeling and algorithmic strategy based on the framework of approximate dynamic programming (ADP) that can model these problems at hourly time increments over an entire year or several decades. We demonstrate the methodology using both spatially aggregate and disaggregate representations of energy supply and demand. This paper describes the initial proof of concept experiments for an ADP-based model called SMART; we describe the modeling and algorithmic strategy and provide comparisons against a deterministic benchmark as well as initial experiments on stochastic data sets.
Effort, performance, and motivation: Insights from robot-assisted training of human golf putting and rat grip strength

Robotic devices can modulate success rates and required effort levels during motor training, but it is unclear how this affects performance gains and motivation. Here we present results from training unimpaired humans in a virtual golf-putting task, and training spinal cord injured (SCI) rats in a grip strength task using robotically modulated success rates and effort levels. Robotic assistance in golf practice increased trainees feelings of competence, and, paradoxically, increased their sense effort, even though it had mixed effects on learning. Reducing effort during a grip strength training task led rats with SCI to practice the task more frequently. However, the more frequent practice of these rats did not cause them to exceed the strength gains achieved by rats that exercised less often at higher required effort levels. These results show that increasing success and decreasing effort with robots increases motivation, but has mixed effects on performance gains.
Protein engineering of nitrile hydratase activity of papain: molecular dynamics study of a mutant and wild-type enzyme.

The mechanism of hydrolysis of the nitrile (N-acetyl-phenylalanyl-2-amino-propionitrile, I) catalyzed by Gln19Glu mutant of papain has been studied by nanosecond molecular dynamics (MD) simulations. MD simulations of the complex of mutant enzyme with I and of mutant enzyme covalently attached to both neutral (II) and protonated (III) thioimidate intermediates were performed. An MD simulation with the wild-type enzyme.I complex was undertaken as a reference. The ion pair between protonated His159 and thiolate of Cys25 is coplanar, and the hydrogen bonding interaction S(-)(25).HD1-ND1(159) is observed throughout MD simulation of the mutant enzyme.I complex. Such a sustained hydrogen bond is absent in nitrile-bound wild-type papain due to the flexibility of the imidazole ring of His159. The nature of the residue at position 19 plays a critical role in the hydrolysis of the covalent thioimidate intermediate. When position 19 represents Glu, the imidazolium ion of His159-ND1(+).Cys25-S(-) ion pair is distant, on average, from the nitrile nitrogen of substrate I. Near attack conformers (NACs) have been identified in which His159-ImH(+) is positioned to initiate a general acid-catalyzed addition of Cys-S(-) to nitrile. Though Glu19-CO(2)H is distant from nitrile nitrogen in the mutant.I structure, MD simulations of the mutant.II covalent adduct finds Glu19-CO(2)H hydrogen bonded to the thioimide nitrogen of II. This hydrogen bonded species is much less stable than the hydrogen bonded Glu19-CO(2)(-) with mutant-bound protonated thioimidate (III). This observation supports Glu19-CO(2)H general acid catalysis of the formation of mutant.III. This is the commitment step in the Gln19Glu mutant catalysis of nitrile hydrolysis.
Study of surface charge of the intima and artificial materials in relation to thrombogenicity

Abstract In vivo , the surface charge (0.3–1.8 × 10 14 electrons/cm 2 ) and the zetapotential (−42 to −120 millivolts) of the intima were determined from the streaming potentials measured in the dog arteries. In vitro , the surface charges (2.8–4.7 × 10 12 electrons/cm 2 ) and the zetapotentials (−4.9 to −8.2 millivolts) of a variety of artificial materials were determined from the streaming potentials measured using physiologic solutions in a specially designed cell. For the artificial materials, the surface charges were similar even though their physical properties were widely different. The nonthrombogenic character of the intima is attributed to its large negative surface charge, and the thrombogenic character of the artificial materials is attributed to their small negative surface charge. It is concluded that in order to make a prosthetic material nonthrombogenic, its surface should be activated to simulate the large negative surface charge of the intima in vivo .
Effects of Aeration, Alum Treatment, Liming, and Organic Matter Application on Phosphorus Exchange between Soil and Water in Aquaculture Ponds at Auburn, Alabama

Application of readily-oxidizable organic substrate to laboratory soil-water systems and fish ponds caused anaerobic conditions in bottom soil and water, and concentrations of soluble reactive phosphorus (SRP) increased. Aeration of ponds increased total phosphorus (TP) concentrations by suspending soil particles in the water, but SRP concentrations declined because of increased oxy- genation of bottom water and soil, Alum [Al2(SO4)3·14H2O] treatment of ponds reduced SRP and TP concentrations in ponds, but the low concentration of alum used, 20 mg/L, had little residual effect on phosphorus concentration. Application of agricultural limestone at 0.2 kg/m2 to ponds with soil pH of 5.5 and Ca2+ concentration of 5 mg/L did not affect SRP and TP concentration. Unless pond soils were anaerobic at their surfaces, a condition not acceptable in thermally-unstratified fish ponds, soils released little phosphorus to the water. Strong adsorption of phosphorus by soils in intensive ponds with feeding is beneficial, because removal of phosphorus by aerobic soils is a control on excessive phytoplankton growth. In fertilized ponds, phosphorus must be applied at frequent intervals to replace phosphorus removed from the water by soils.
Asymmetric Chiral Ligand-Directed Alkene Dioxygenation

A Pd-catalyzed asymmetric alkene 1,2-dioxygenation reaction is described. The diastereoselectivity of the reaction is controlled by tethering a chiral oxime ether directing group to the alkene substrate. The best selectivities are obtained with 8-substituted menthone-derived oxime ether auxiliaries.
An Axisymmetric Membrane Element With Bending Stiffness for Static Implicit Sheet Metal Forming Simulation

This paper reviews techniques to include the bending behavior of sheet metals into finite element method formulations. A new, numerically efficient bending correction for the implementation into axisymmetric membrane elements is developed. This bending correction is based on a number of simplifying assumptions. The accuracy of the implementation is demonstrated by analyzing two round cup drawings for which experimental measurements were available from the literature. The range of applicability of the proposed approach is discussed.
A TWO-BODY CLUSTER MODEL OF THE NUCLEUS

Calculations are presented for coupled Schrodinger equations which develop the detailed behavior predicted by the two-body cluster model described in a preceding paper. The results show that: 1) narrow resonances in the scattering cross section may be quantitatively described by this model, 2) the cross section in the neighborhood of the threshold of another channel shows the Wigner cusp, and 3) the configuration mixing of bound states is a necessary consequence of the model. As an example, the model is used as a means of parameterizing the lowest states in C^(13). This method allows a fit to the scattering phase shift and the level structure, at the same time making a definite prediction of the fractional parentage of the bound state.
Cadmium, chromium, and cardiovascular disease.

Observations made in the last 15 years by the author and others concerning the effect of trace metals, particularly cadmium and chromium, on animals and man are reviewed with special reference to hypertension and atherosclerosis. These trace metals come from the soil or sea. Among the topics covered are cadmium hypertension in rats, diabetes mellitus and chromium deficiency, deficiency sources, and possible losses of chromium, and the influence of drinking water on death rates from atherosclerosis. The conclusions are that one common form of hypertension is probably an example of accumulation of cadmium in the kidney and that deficiency of chromium may influence glucose and lipid metabolism and affect atherosclerosis. Other trace elements may contribute also.
VENTRICULAR ANEURYSM. A REAPPRAISAL BASED ON A STUDY OF SIXTY-FIVE CONSECUTIVE AUTOPSIED CASES.

Sixty-five consecutive autopsied cases of ventricular aneurysm are reviewed. The incidence of aneurysm following myocardial infarction is similar to that reported in other series. Myocardial infarction preceded the formation of an aneurysm of the ventricle in the vast majority of patients, and a new myocardial infarction was the cause of death of about 50 per cent of them. The survival rate of patients with ventricular aneurysm is not significantly different from the long-term survival of all patients with myocardial infarction found in the same institution. Complications of ventricular aneurysm such as chronic congestive heart failure and rupture of the aneurysm were infrequent causes of death, and systemic embolic phenomena were not observed as a cause of death. In only four patients was the diagnosis made ante mortem. The lack of characteristic clinical, radiologic, and electrocardiographic findings is discussed. It is suggested that the hemodynamic significance of ventricular aneurysms is not ordinarily great, in view of the unaffected statistical prognosis in its presence. The recommended indications for surgery of ventricular aneurysms, based on this retrospective study, are presented.