cssi/SciSciGPT-SciSciNet huggingface dataset:
Structural studies of myosin:nucleotide complexes: a revised model for the molecular basis of muscle contraction.

Abstract The structures of the MgADP-beryllium fluoride and MgADP-aluminum fluoride complexes of the truncated myosin head from Dictyostelium myosin II are reported. These reveal the location of the nucleotide complex and define the amino acid residues that form the active site. The tertiary structure of the beryllium fluoride complex is essentially identical to that seen previously in the three-dimensional structure of chicken skeletal muscle myosin. By contrast, significant domain movements are observed in the aluminum fluoride complex. These structural findings form the basis of a revised model for the structural basis of the contractile cycle. It is now suggested that the narrow cleft that splits the central 50-kDa segment of the heavy chain provides not only the communication route between the nucleotide-binding pocket and actin but also transmits the conformational change necessary for movement.
Performance of Reed-Solomon coded M-ary modulation systems with overlapped symbols

We analyzed the bit error probability of a single RS codeword with symbol overlapping. By symbol overlapping, we mean that the bits in each modulation symbol can belong to 2 or more RS symbols and vice versa. We propose two novel designs for Reed-Solomon (RS) coded modulation with symbol overlapping. For an RS code with symbol size GF(2n), the information bits are first RS coded. For the first strategy, the coded bits are matrix interleaved prior to modulation and for the second strategy, the RS symbols are matrix interleaved and the resulting coded symbols are shifted circularly by n/2 bits prior to modulation. In this paper, we considered a M = 2n-ary modulation scheme. The received signal is demodulated appropriately, de-interleaved and RS decoded. The decoded symbols are interleaved and sent to the demodulator where it makes use of the decoded symbols from other codewords to re-demodulate the signals. This process is repeated until there is no improvement in the bit error rate. It is observed that this simple coded modulation design scheme has about 0.5 dB better performance than one that does not employ symbol overlapping over an AWGN channel at bit error rate of 10-3. An improvement of 1 dB is observed over a Rayleigh fading channel
Validity of diagnostic codes and laboratory tests of liver dysfunction to identify acute liver failure events

Purpose Identification of acute liver failure (ALF) is important for post-marketing surveillance of medications, but the validity of using ICD-9 diagnoses and laboratory data to identify these events within electronic health records is unknown. We examined positive predictive values (PPVs) of hospital ICD-9 diagnoses and laboratory tests of liver dysfunction for identifying ALF within a large, community-based integrated care organization.
Multinational Mars exploration

A primary concern in the formation of a multinational Mars-exploration program is that of technology transfer, which would be most acute in the U.S./U.S.S.R. case but would exist in lesser degree among other nations. Another concern is that of management-complexity, which could inflate total costs and substantially counteract the anticipated benefits of spreading program costs among a number of nations. It is presently suggested that these problems can be substantially reduced by having each nation become responsible for one (or more) complete flight system. Each nation's role in mission operations must be clear, and the cleanliness of interfaces among flight systems must carry over into mission operations.
How Do Humans Acquire Knowledge? And What Does That Imply About the Nature of Knowledge?

This paper offers a resolution to the debate between constructivists andrealists regarding the epistemological status of human knowledge. Evidence in the form of three case studies and one experimentalstudy is presented. The conclusion drawn is that knowledge acquisitioninvolves a pattern of idea (representation) generation and test that, whencast in the form of a verbal argument, follows an If/then/Thereforepattern. Self-generated ideas/representations are tested by comparingexpected and observed outcomes. Ideas may be retained or rejected,but can not be proved or disproved. Therefore, absolute Truth aboutany and all ideas, including the idea that the external world exists, isunattainable. Yet learning at all levels above the sensory-motor requiresthat one assume the independent existence of the external world becauseonly then can the behavior of the objects in that world be used to testsubsequent higher-order ideas. In the final analysis, ideas – includingscientific hypotheses and theories – stand or fall, not due to socialnegotiation, but due to their ability to predict future events. Althoughthe knowledge acquisition process has limitations, its use neverthelessresults in increasingly useful representations about an assumed to existexternal world as evidenced by technological progress that is undeniablybased on sound scientific theory. The primary instructional implicationis that science instruction should remain committed to helping studentsunderstand the crucial role played by hypotheses, predictions and evidencein learning.
ELF/VLF wave generation from the beating of two HF ionospheric heating sources

[1] It is well established that Extremely Low Frequency (ELF, 0.3–3 kHz) and Very Low Frequency (VLF, 3–30 kHz) radio waves can be generated via modulated High Frequency (HF, 3–10 MHz) heating of the lower ionosphere (60–100 km). The ionospheric absorption of HF power modifies the conductivity of the lower ionosphere, which in the presence of natural currents such as the auroral electrojet, creates an ‘antenna in the sky.’ We utilize a theoretical model of the HF to ELF/VLF conversion and the ELF/VLF propagation, and calculate the amplitudes of the generated ELF/VLF waves when two HF heating waves, separated by the ELF/VLF frequency, are transmitted from two adjacent locations. The resulting ELF/VLF radiation pattern exhibits a strong directional dependence (as much as 15 dB) that depends on the physical spacing of the two HF sources. This beat wave source can produce signals 10–20 dB stronger than those generated using amplitude modulation, particularly for frequencies greater than 5–10 kHz. We evaluate recent suggestions that beating two HF waves generates ELF/VLF waves in the F-region (>150 km), and conclude that those experimental results may have misinterpreted, and can be explained strictly by the much more well established D region mechanism.
Active Feeding Behavior Compensates for Low Interest in Food among Young Nicaraguan Children

The association of caregivers' feeding behavior with young children's anthropometric status was examined in 80 poor urban families from Nicaragua. Caregiver and child behaviors observed during eating were recorded for midday meals, snacks and bottle feeds. Two kinds of scales were constructed. The Active Feeding Scale measured the caregiver's attempts to encourage or promote the child's food ingestion through behaviors such as verbal encouragement, threatening, offering more food or demonstrating eating. The Child Demand Scale measured the child's interest and enthusiasm for food. Results suggested the following: 1) there were significant differences in caregiver encouragement of feeding by meal type (midday meal, snack or bottle-feed); 2) mothers were significantly more likely to encourage eating than were other caregivers; and 3) active feeding was not associated with child anthropometric status but often appeared to be associated with child disinterest in the meal. It is suggested that active feeding may be used to compensate for child disinterest in food rather than to enhance the child's growth and developmental trajectory. The importance of lack of child interest in food, probably related to poor appetite, needs to be recognized and incorporated into nutrition education programs.
Parallel optical generation of the binomial probability functions

Abstract A parallel optical binomial probability density and distribution function generation method is proposed. Based on a N -level triangular lattice type optical network, all possible N + 1 binomial probability values are obtainable. Using a polarization switch together with various half-wave retardation plates, beamsplitters, a key optical mapping cell is described. With a slight modification, the design of an optical parallel binomial random sequence generator is also presented.
Lower abdominal wall flap for closure of large diaphragmatic defects

A method of closure of diaphragmatic herniae with large defects is described in two children using a muscle flap of internal oblique and transversus abdominus from the inferior aspect of the wound. The advantages are that the flap is large, easily accessible, autologous, assists in resultant wound closure, and requires no separate incision. It differs from previously described flaps as it is taken from below the subcostal wound and is not limited in size or length by the costal margin.
Bile Acid Metabolism in Cirrhosis. VIII. Quantitative Evaluation of Bile Acid Synthesis From [7β‐3H]7α‐Hydroxycholesterol and [G‐3H]26‐Hydroxycholesterol

In order to evaluate more definitively the observed aberrations in the synthesis of cholic and chenodeoxycholic acids in patients with advanced cirrhosis, two bile acid biosynthesis pathways were examined by determining the efficiency of conversion of [3H]7 alpha-hydroxycholesterol and [3H] 26-hydroxycholesterol to primary bile acids. Bile acid kinetics were determined by administration of [14C]cholic and [14C]chenodeoxycholic acids. Cholic acid synthesis in cirrhotic patients was markedly depressed (170 vs. 927 mumoles per day)( while chenodeoxycholic acid synthesis was reduced to a much lesser degree (227 vs. 550 mumoles per day). The administration of [3H]7 alpha-hydroxycholesterol allowed for an evaluation of the major pathway of bile acid synthesis via the 7 alpha-hydroxylation of cholesterol. This compound was efficiently incorporated into primary bile acids by the two normal subjects (88 and 100%) and two cirrhotic patients (77 and 91%). However, the recovery of the label in cholic acid was slightly less in cirrhotic patients than in normal subjects. [3H]26-hydroxycholesterol was administered to ascertain the contribution of the 26-hydroxylation pathway to bile acid synthesis. All study subjects showed poor conversion (9 to 22%) of this intermediate into bile acids. The results of this study suggest that a major block in the bile acid synthesis pathway in cirrhosis is at the level of 7 alpha-hydroxylation of cholesterol (impairment of 7 alpha-hydroxylase) and /or in the feedback triggering mechanism regulating bile acid synthesis. The data also suggest that the 26-hydroxylation pathway in normal subjects and patients with cirrhosis is a minor contributor to synthesis of the primary bile acids. Therefore, the relative sparing of chenodeoxycholic acid synthesis observed in cirrhotic patients is not due to preferential synthesis of this bile acid via the 26-hydroxylation pathway.
Aggressiveness and learning ability: Effect of histories of wins or defeats on avoidance learning in mice

Thirty-two mice, exposed to a series of fighting matches designed to elicit aggressive behavior, tended to become either dominant or submissive. When later trained on an avoidance task, submissive Ss learned significantly faster than dominant Ss. These results lend support to the hypothesis that the tendency for a dominant animal to respond with aggressiveness is maladaptive and leads to slower learning, whereas the tendency for a submissive animal to escape or avoid is adaptive and leads to faster learning.
Cervical Spine Movement Sequencing During Flexion-Extension

Static flexion-extension x-rays are the most common clinical tool used to assess abnormal motion of the cervical spine. Despite their widespread use (over 168,000 cases per year), the clinical efficacy of flexion-extension radiographs of the cervical spine has yet to be proven1. Limitations of static flexion-extension x-rays include data collection during static positions that may not accurately represent dynamic behavior, and the fact that data is collected at end range of motion positions, not in more frequently encountered mid-range positions. Consequently, static x-rays may not reveal movement abnormalities that occur during activities of daily living and lead to pain and degeneration. Therefore, it may be advantageous to analyze cervical spine kinematic data collected during dynamic, functional movements performed through an entire range of motion (not just the endpoints). Furthermore, the literature confirms there is substantial variability in “normal” range of motion and translation during flexion-extension1, making it difficult to reliably identify abnormal motion. Therefore, it may also be beneficial to evaluate alternative motion parameters that may reliably identify abnormal motion.Copyright © 2011 by ASME
A relation context oriented approach to identify strong ties in social networks

Strong ties play a crucial role in transmitting sensitive information in social networks, especially in the criminal justice domain. However, large social networks containing many entities and relations may also contain a large amount of noisy data. Thus, identifying strong ties accurately and efficiently within such a network poses a major challenge. This paper presents a novel approach to address the noise problem. We transform the original social network graph into a relation context-oriented edge-dual graph by adding new nodes to the original graph based on abstracting the relation contexts from the original edges (relations). Then we compute the local k-connectivity between two given nodes. This produces a measure of the robustness of the relations. To evaluate the correctness and the efficiency of this measure, we conducted an implementation of a system which integrated a total of 450 GB of data from several different data sources. The discovered social network contains 4,906,460 nodes (individuals) and 211,403,212 edges. Our experiments are based on 700 co-offenders involved in robbery crimes. The experimental results show that most strong ties are formed with k ≥ 2.
Evaluation of acellular human dermis reinforcement of the crural closure in patients with difficult hiatal hernias.

Biologic prosthetics may circumvent mesh-related complications at the esophageal hiatus by becoming remodeled by native cells. We present our experience with acellular human dermal matrix in the repair of difficult hiatal hernias (HH). Records of 17 patients who underwent laparoscopic HH repair using acellular human dermis to buttress the crural closure were analyzed. Hernias were paraesophageal (PEH) in 12 patients, large type 1 in 1 patient, and recurrent after prior HH repair in 4 patients. Barium swallow (BAS) was obtained 6–12 months after surgery. (Data are presented as mean ± standard deviation.) Mean patient age was 65 ± 12 years and BMI was 31 ± 4. Mean gastroesophageal (GE) junction distance above the diaphragm in the PEHs was 4.9 ± 1.5 cm; 9 of 12 patients with PEH had more than 50% of the stomach in the chest. Mean operating time was 273 ± 48 min. Average hiatal defect size was 4.7 × 2.7 cm, with 4.2 ± 1.2 sutures used to close the crura. Nissen fundoplication was performed in all patients, esophageal lengthening in four patients, and anterior gastropexy in three patients. Mean hospital length of stay (LOS) was 2.3 ± 0.8 days. Mean followup was 14.4 ± 4.4 months. Postoperatively, only one (6%) patient had heartburn/regurgitation, one (6%) had mild dysphagia, and two (12%) take proton pump inhibitors. Followup BAS at 10.3 ± 4.9 months after surgery showed small recurrent hernias in two patients (12%), but only one was symptomatic. In addition, there was one symptomatic failure of a redo Nissen in an obese patient. Reoperative gastric bypass 15 months later showed an intact crural closure with a remodeled buttress site. Acellular human dermal matrix may be an effective method to buttress the crural closure in patients with large hiatal hernias. Longer followup in larger numbers of patients is needed to assess the validity of this approach.
111In-CYT-103 scanning in recurrent colorectal cancer—Does it affect standard management?

PURPOSE: In a blinded fashion, radiolabeled B72.3 was investigated in operative cases of recurrent colorectal cancer to determine if diagnostic accuracy would be improved to ultimately maximize curability and minimize interventional morbidities. METHODS: Study patients underwent conventional evaluation including history, physical examination, abdominal/pelvic computed tomographic scan (CT), colon examination, and carcinoembryonic antigen (CEA) determination, with select magnetic resonance imaging and ultrasonographic imaging as indicated. Murine monoclonal antibody B72.3 was labeled with indium-111 (111In-CYT-103 provided by Cytogen) and scans obtained at 48 hours and, selectively, at 72 and 96 hours. Unlike previous studies, the operating surgeon was blinded to111In-CYT-103 abdominal scan results until surgical exploration was complete. RESULTS: Of 15 study patients (10 male; 5 female), average age was 57 years, and average CEA was 10 ng/ml (with eight elevated CEA levels). A single patient did not undergo surgery because of presence of pulmonary metastases identified on CT scan but not identified on a111In-CYT-103 scan. Laparotomies included resection and intraoperative radiation (10), resection alone (1), and biopsy only (3). CT and111In-CYT-103 scans were compared with operative findings. CT scans had an accuracy and positive predictive value of 47 and 100 percent, respectively, whereas those of111In-CYT-103 scan were 60 and 82 percent, respectively. Contribution of the scan to diagnosis and management was graded by the surgeon as no effect (67 percent), beneficial effect (13 percent), or negative effect (20 percent). CONCLUSIONS:111In-CYT-103 was more accurate compared with CT scan, but when value of the scan was examined with respect to its potential contribution to patient management, it was beneficial in only 13 percent of patients. Further refinements may enhance the value of antibody imaging techniques.
Brief paper: Singular perturbation analysis of a receding horizon controller

A new receding horizon approach to the linear regulator problem is presented. At each instant of time, the control strategy is based on the minimization of a quadratic performance index extending over an interval of fixed length into the future. Connections with standard results are discussed and, under general assumptions, the closed-loop system is shown to be asymptotically stable. A potential advantage of our method lies in the fact that a singular perturbation analysis is well posed. This indicates that, for plants containing slow and fast modes, the design procedure can be split up into two stages. The resulting composite control exhibits attractive engineering properties. Use and effectiveness of the proposed techniques are demonstrated by investigating a practical example.
Diet and Colour of Birds

DURING the past year (1935), work was begun to improve the feeding routine of all animal groups at the Zoological Garden in Philadelphia. Efforts are being made to devise food mixtures that are complete in all known essentials, contain a wide variety of materials and allow for seasonal abundance so as to be economical, and are similar in general physical characters to natural foods. From time to time, various factors have necessitated modifications of formulae, so that complete descriptions of the diets to which reference will be made are better postponed. Eventually records of these studies will be used as the subject matter of a report on methods of feeding wild animals in captivity. In spite of the present incompleteness of the investigation, however, certain effects of changes in diet upon the colours of the plumage of several species of birds seem worthy of record at this time.
Term premiums and the integration of the eurocurrency markets

Abstract This paper provides comparative evidence on the time variation of expected returns across the term of Eurocurrency markets. First, it is shown that forward-spot spreads contain substanial information about future changed in 1-month to 5-year rates, both in the Eurodollar and EuroDM markets. Next, a latent variable model is constructed with different benchmark portfolios across currencies. Integration implies that the time variation of the benchmark portfolios must be the same across currencies. Little evidence is found against integration of the Eurocurrency markets. (JEL G15, G12).
Phase Diagram of Precipitation Morphologies in the Cu2+−PO43- System

We have experimentally investigated the phase diagram of spatiotemporal pattern formation in the precipitation reaction of copper sulfate and sodium phosphate. The system exhibits an unusual variety of both vertically and horizontally growing structures. Quantitative measurements have been used to analyze the transition between the two patterns. The driving forces for the pattern formation have been identified as osmosis, buoyant forces, flow rate, and the mechanical properties of the membrane.
Theoretical study of excitation energy transfer in DNA photolyase.

Photolyase (PL) is a DNA repair enzyme which splits UV light-induced thymine dimers on DNA by an electron transfer reaction occurring between the photoactivated FADH - cofactor and the DNA dimer in the DNA/PL complex. The crystal structure of the DNA/photolyase complex from Anacystis nidulans has been solved. Here, using the experimental crystal structure, we re-examine the details of the repair electron transfer reaction and address the question of energy transfer from the antenna HDF to the redox active FADH - cofactor. The photoactivation of FADH - immediately preceding the electron transfer is a key step in the repair mechanism that is largely left unexamined theoretically. An important butterfly thermal motion of flavin is identified in ab initio calculations; we propose its role in the back electron transfer from DNA to photolyase. Molecular dynamics simulation of the whole protein/DNA complex is carried out to obtain relevant cofactor conformations for ZINDO/S spectroscopic absorption and fluorescence calculations. We find that significant thermal broadening of the spectral lines, due to protein dynamics, as well as the alignment of the donor HDF and the acceptor FADH - transition dipole moments both contribute to the efficiency of energy transfer. The geometric factor of Forster's dipolar coupling is calculated to be 1.82, a large increase from the experimentally estimated 0.67. Using Forster's mechanism, we find that the energy transfer occurs with remarkable efficiency, comparable with the experimentally determined value of 98%.
A Unified Framework of Node Mobility Models

A mobile ad hoc network (MANET) consists of mobile nodes that communicate with each other without any infrastructure. MANET has various applications including military operations, rescue operations, and many other situations that require rapidly deployable communication networks. In order to evaluate the performance of such networks accurately through simulations, we need to use realistic conditions when simulating. User mobility pattern is an important factor that affects the performance of the network significantly. Recently, a number of mobility models have been proposed in order to produce realistic node mobility patterns. Mobility models differ considerably depending on the applications for which they are designed. In this paper, we present a unified mobility model framework. The framework can generate most of widely used mobility models with a short script. We show this by applying the framework to generate most of the existing mobility models. This framework expedites the performance evaluation process of MANETs since users do not need to write code from scratch to generate the application-specific moving patterns for the nodes.
A Comparison of the Mechanical and Structural Properties of Fibrin Fibers with Other Protein Fibers

In the past few years a great deal of progress has been made in studying the mechanical and structural properties of biological protein fibers. Here, we compare and review the stiffness (Young’s modulus, E) and breaking strain (also called rupture strain or extensibility, emax) of numerous biological protein fibers in light of the recently reported mechanical properties of fibrin fibers. Emphasis is also placed on the structural features and molecular mechanisms that endow biological protein fibers with their respective mechanical properties. Generally, stiff biological protein fibers have a Young’s modulus on the order of a few Gigapascal and are not very extensible (emax 100%). These soft, extensible fibers employ a variety of molecular mechanisms, such as extending amorphous regions or unfolding protein domains, to accommodate large strains. We conclude our review by proposing a novel model of how fibrin fibers might achieve their extremely large extensibility, despite the regular arrangement of the monomeric fibrin units within a fiber. We propose that fibrin fibers accommodate large strains by two major mechanisms: (1) an α-helix to β-strand conversion of the coiled coils; (2) a partial unfolding of the globular C-terminal domain of the γ-chain.
Optimizing the automatic selection of spike detection thresholds using a multiple of the noise level

Thresholding is an often-used method of spike detection for implantable neural signal processors due to its computational simplicity. A means for automatically selecting the threshold is desirable, especially for high channel count data acquisition systems. Estimating the noise level and setting the threshold to a multiple of this level is a computationally simple means of automatically selecting a threshold. We present an analysis of this method as it is commonly applied to neural waveforms. Four different operators were used to estimate the noise level in neural waveforms and set thresholds for spike detection. An optimal multiplier was identified for each noise measure using a metric appropriate for a brain-machine interface application. The commonly used root-mean-square operator was found to be least advantageous for setting the threshold. Investigators using this form of automatic threshold selection or developing new unsupervised methods can benefit from the optimization framework presented here.
SU-E-J-116: Investigation of Accuracy and Precision of ITV Delineation by PET SUV Threshold.

Purpose: To determine PET SUV values in Pinnacle TPS and to assess the accuracy and precision of the ITV according to SUV thresholds. The goal is to minimize errors in target definition by using SUV showing enhanced metabolic activity of the tumor and fast CTimaging with less motion artifacts. Methods: Mean PET values in individual patients were obtained from statistics of body contours for whole body PET‐CT scans. The SUVs were calculated by normalizing the PET values in any voxel by the mean body PET value. These clinically acquired SUVs were plotted against values reported at the time of the scan for verification. GTVs were contoured on petCT scans and the ITV's were contoured using three published methods of SUV thresholds at 2.5, at ratio of 40 percent of the maximum, and 30 percent of the maximum added to 60 percent of the mean body. GTV volumes were plotted against the 3 sets of ITVs to investigate their relationships. Results: Examination of 11 patients showed a strong linear relationship between clinically determined SUVs and those reported; indicating the validity of our SUV definition. Plots of GTV volumes versus ITV volumes for each of the 3 thresholds revealed a less clear relationship. The effectiveness of each method to generate a reasonable ITV was highly patient dependent; in general the 2.5 threshold gave the best results, while the 40 percent maximum produced the worst. Conclusions: While more data is required to make a definitive statement about the value of PET SUV threshold defined ITVs, the findings do seem to reveal a pattern between GTV and ITV size. If an appropriate SUV threshold is chosen, the GTV‐ITV volume relationship is nearly linear, which suggests extending the GTV in volume rather than the margin distance as is common in ITV delineation.
Outcomes of Emergency Surgical Airway Procedures in a Hospital‐Wide Setting

Objective: To review the circumstances, complications, and outcomes of emergency surgical airway procedures and to compare the relative merits of cricothyroidotomy and tracheotomy for airway control in a hospital-wide patient population. Study Design: Retrospective review. Methods: Patient data were obtained from the inpatient charts and electronic patient records of 35 patients who required an emergency surgical airway over a 6-year period at an urban medical center. Results: Emergency cricothyroidotomy and tracheotomy were successfully performed in 34 of 35 patients (97%). Orotracheal intubation was successfully achieved in one patient with a failed cricothyroidotomy. The overall complication rates for emergency cricothyroidotomy and tracheotomy were similar (20% and 21%, respectively). Inpatients requiring an emergency surgical airway had a higher complication rate (32% vs. 0%) but better overall survival (91% vs. 46%) than patients treated in the emergency department. No long-term complications were observed from emergency cricothyroidotomies that were not converted to tracheotomies. Conclusion: The establishment of an emergency surgical airway by either tracheotomy or cricothyroidotomy is effective with low overall morbidity. The need to convert every emergency cricothyroidotomy to a tracheotomy should be reevaluated.
Role of Surface Tension in the Formation of Membrane Tubes

The formation of tubular structures is a fundamental morphological change that takes place in biological and reconstituted lipid membranes. Mechanical tension in biological membranes is thought to potentially regulate a number of cellular processes, including cell migration. Here, we explore the impact of surface tension on the formation of membrane tubes using elastic and viscoelastic continuum models of lipid bilayers. In the elastic framework, we demonstrate that application of a point load is sufficient to drive the formation of a tube from an initially flat patch of membrane which undergoes a tent-to-tube transition as a region of negative Gaussian curvature develops at the base of the tube. We generate force vs. displacement curves over several orders of magnitude in the surface tension that display a characteristic overshoot of approximately 13% in the force required to maintain a tube at constant length for all values of surface tension. Additionally, we observe a larger (smaller) linear deformation of the patch relative to the tube radius for a membrane under greater (lesser) tension. We also develop a viscoelastic framework that accounts for lipid flow on the membrane surface on a time scale set by the surface viscosity of the membrane. One key feature of this model is that it expressly allows for the local tension to vary as lipids flow within the plane of the membrane. Using this model we calculate lipid velocity as a function of curvature and local tension during tube formation. Additionally, we make comparisons between the force vs. displacement curves obtained from the viscoelastic model to those obtained via the elastic model.
Effects of Ipsilateral Wing-Wing Interactions on Aerodynamic Performance of Flapping Wings

Dragonflies are masters of using the ipsilateral wing-wing interaction for different kinds of flying modes. It has been discovered that the phase difference between ipsilateral forewings and hindwings plays important role on wing aerodynamic performance. In the current study, we continue our research of a modeled dragonfly in slow flight (Liang and Dong (2009)) by varying the phase difference between the forewings and hindwings and look at the changes of aerodynamic performance of hindwings. Results of this work will help with the design of quadwinged MAVs. NOMENCLATURE Ψf flapping or azimuth angle of forewing, deg Ψh flapping or azimuth angle of hindwing, deg ω angular rate of flapping motion, rad/s △δ phase difference of azimuth angle between forewing and hindwing, deg
An Improved Method of Coronary Arteriography

Upon inspection of current mortality tables, even the most phlegmatic must agree that there is a clear and compelling reason for improving our therapeutic approach to coronary occlusive disease. Add to this the untold suffering and disability resulting from coronary occlusion and the argument literally becomes a “clarion call that brooks no denial.” Since coronary insufficiency is a result of vascular narrowing, coronary surgery appears to be the most promising avenue of attack. Although relativelyfew patientsmight have sufficiently localized lesions to justify surgery, even a small proportion of the half million fatal cases each year would represent a worthwhile salvage. However, if coronary surgery is to be rationally applied, there must first be a means for determining which patients are suitable candidates for operation. No method short of actual visualization-either by radiological technics or under direct inspectioncan accomplish this important objective. Thus, the desirability of a safe, easily-applied, and diagnostically-reliable method of preoperatively demonstrating diseased coronary arteries seems clearly established. Historical Reports of incidental as well as intentional radiological demonstrations of the coronary vessels date back at least to 1933, with Rousth#{246}i1 and Reboul and Racine2 in the vanguard. Since that time, there have been numerous reports describing coronary arteriography in experimental animals. It appears that man’s coronary arteries were first demonstrated during life by Radner3 in 1945. The earliest large series of coronary visualizations in man, however, is attributable to J#{246}nsson4 who used retrograde’ thoracic aortography via a catheter inserted into a peripheral artery. Most of the retrograde aortograms in this series were done for the study of congenital cardiovascular abnormalities; coronary visualization was merely incidental. Other workers512 have used various aortographic technics-including retrograde arterialcatheterization,directneedle puncture of the ascending aorta, and transthoracic left ventricular needling-specifically for the purpose of demonstrating the coronary circulation. With each of these methods, successful demonstration of coronary vessels required invariably large and sometimes overwhelming doses of concentrated iodine-containing contrast media in order to counteract dilution effects. Even then, there was no assurance that the contrast medium would flow into one or both coronary arteries in sufficient concentration to pro
SUMOylation of ATRIP potentiates DNA damage signaling by boosting multiple protein interactions in the ATR pathway

The ATR (ATM [ataxia telangiectasia-mutated]- and Rad3-related) checkpoint is a crucial DNA damage signaling pathway. While the ATR pathway is known to transmit DNA damage signals through the ATR-Chk1 kinase cascade, whether post-translational modifications other than phosphorylation are important for this pathway remains largely unknown. Here, we show that protein SUMOylation plays a key role in the ATR pathway. ATRIP, the regulatory partner of ATR, is modified by SUMO2/3 at K234 and K289. An ATRIP mutant lacking the SUMOylation sites fails to localize to DNA damage and support ATR activation efficiently. Surprisingly, the ATRIP SUMOylation mutant is compromised in the interaction with a protein group, rather than a single protein, in the ATR pathway. Multiple ATRIP-interacting proteins, including ATR, RPA70, TopBP1, and the MRE11-RAD50-NBS1 complex, exhibit reduced binding to the ATRIP SUMOylation mutant in cells and display affinity for SUMO2 chains in vitro, suggesting that they bind not only ATRIP but also SUMO. Fusion of a SUMO2 chain to the ATRIP SUMOylation mutant enhances its interaction with the protein group and partially suppresses its localization and functional defects, revealing that ATRIP SUMOylation promotes ATR activation by providing a unique type of protein glue that boosts multiple protein interactions along the ATR pathway.
Does an amniotic fluid index of ≤5 cm necessitate delivery in high- risk pregnancies? A case-control study

Abstract Objective: This study was undertaken to determine whether women with high-risk pregnancies and an amniotic fluid index of ≤5 cm require labor induction to prevent adverse perinatal outcomes. Study Design: All women at high risk at ≥34 weeks' gestation with an amniotic fluid index of ≤5 cm were admitted to the hospital for labor induction. Each woman was compared with the next patient at high risk seen with an amniotic fluid index of >5 cm and the same pregnancy complication. Case patients were also matched with control subjects for maternal race, age, parity, and gestational age. Results: Prospectively, 79 women at high risk with an amniotic fluid index of ≤5 cm were compared with 79 control subjects. There were no statistically significant differences between the 2 groups in the risks of thick meconium ( P = .29), variable decelerations (moderate P = .27, severe P = .37), amnioinfusion ( P = .37), cesarean delivery for fetal distress ( P = .4), and umbilical artery pH P = .29). Conclusion: High-risk pregnancies with an amniotic fluid index of ≤5 cm appear to carry intrapartum complication rates similar to those of similar high-risk pregnancies with an amniotic fluid index of >5. (Am J Obstet Gynecol 1999;180:1354-9.)
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Logic, liberty, and anarchy: Mill and Feyerabend on scientific method

Abstract On the surface, J. S. Mill and Paul Feyerabend appear to hold differing views of scientific method. Mill attempts to frame a set of rules or canons for testing evidence based on rationality and inference, whereas Feyerabend, in his so-called “epistemological anarchism”, calls for abandoning any attempt to separate the good from the bad in science according to a fixed view of rationality. Yet, somewhat paradoxically, Feryerabend cites Mill as the originator of what he (Feyerabend) has to say in defense of epistemological anarchy. First, I argue that those aspects of Mill’s On Liberty that are suggestive of an anti-rationalist philosophy are entirely compatible with the theory of scientific method Mill offers in A System of Logic . Second, in the process of reconciling these two works of Mill, I hope to shed light on how we are to understand Feyerabend’s critique of methodological dogmatism.
Extractability of protein in physically processed rice bran

Commercially obtained defatted (DF), full-fat stabilized (FFS), and full-fat unstabilized (FFU) rice bran were processed by colloid milling and homogenization to affect bran breakdown and extraction of rice protein. Relative to unprocessed samples, there were moderate to slight increases in the amount of protein extracted from the various fractions of processed bran. Colloid milling and homogenizing slightly influenced the distribution of proteins in the various fractions obtained, with the FFU showing the greatest effect compared to DF and FFS protein fractions. The protein content of the supernatant fraction of FFU bran increased from 21.8 to 33.0% after colloid milling with a further increase to 38.2% after homogenizing, representing an overall increase of 75.2% in protein content. The supernatant fractions of DF bran increased from 13.9 to 14.7% after colloid milling, and to 16.5% after colloid milling and homogenizing, for an overall increase of 18.7%. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed a molecular weight distribution ranging from 6.0 to 97.4 kDa. Few detectable differences between protein bands of unprocessed and processed DF and FFU bran were observed. However, FFS bran showed breakdown in size distribution of protein after colloid milling and homogenizing, because certain high molecular weight proteins shifted to lower molecular weight units.
Polarized Induced Magnetic Broadening of Photonic Activities in Fe 3 O 4 -Elastomer Composites

We report a systematic study of polarization and magnetic field effects on the optical response of Fe 3 O 4 -silicone elastomer composite. The Fe 3 O 4 particles were aligned in a silicone elastomer matrix with an external static magnetic field. Films of composites containing 5wt% of 20nm ≤ d ≤ 30nm Fe 3 O 4 particles aligned in- and out-of-plane in the elastomer host were prepared. The optical spectra of the films were measured with the Perkin-Elmer Lambda 950 UV/vis/NIR spectrometer. We observed a systematic redshift in the optical response of the outof-plane composite films with increasing static magnetic field strength, which saturated near 600 Gauss. We obtained a maximum redshift of ∼46 nm at 600 Gauss. The observed redshift in the optical response of the out-of-plane composite film is attributed to the effect of the magnetic field. This facilitated the formation of the highly aligned particles that induced strong electric dipole in the aligned particles. Interestingly, there were no observable shifts with increasing magnetic field strength in the in-plane films, suggesting that the orientation (polarization) of the magnetic dipole and the induced electric dipole play a crucial role in the optical response.
Covariation in macrostratigraphic and macroevolutionary patterns in the marine record of North America

Students of Earth history have long recog- nized the correlation between the quantity of preserved sedimentary rock and the diversity of life recorded as fossils. But paleontologists have yet to determine whether this pattern refl ects a causal relationship or a unidirec- tional sampling bias in fossil data imposed by preserved rock quantity. Distinguishing between these two alternatives has been com- plicated by the fact that many of the basic patterns of paleontologic and lithologic co- variation have yet to be quantifi ed rigorously. Here we present the fi rst analyses of the co- variation between the macrostratigraphic and macroevolutionary histories of North America based on geographically and tem- porally explicit co-occurrences of rocks and fossils. The analyses use independent quan- titative summaries of the stratigraphic and fossil records by integrating the Paleobiology Database (PaleoDB) and Macrostrat, a mac- rostratigraphy database for North America, which allows a more direct comparison of the stratigraphic and biological histories of the continent than has heretofore been possible. Within the Macrostrat database, the rock re- cord is divided into discrete packages of sedi- ment that are bound by hiatuses resolvable at the stage-level. Using per interval, per pack- age rates of sediment package initiation and truncation, and genus fi rst and last appear- ances (herein regional origination and extinc- tion), we fia substantially stronger positive correlation between sediments and biology for extinction-like parameters than we do for origination-like parameters. Four of the largest coincident pulses of regional extinc- tion and sediment truncation occur during the widely recognized end-Ordovician, late Permian, end-Triassic, and end-Cretaceous mass extinction intervals. A further compari- son of the global ranges of North American genera to North American macrostratigra- phy indicates that the regional and global extinction of genera are more likely to oc- cur in the same stage than are global and regional originations. Together, these results suggest that our general understanding of biodiversity dynamics from the fossil record may not be strongly biased by the preserva- tion of sediments and leaves open the pos- sibility that certain large perturbations to the Earth system are responsible for major changes of state in both the sedimentary and biological systems.
WE‐C‐BRC‐10: The Utility of Surrogates of the Distribution of Pulmonary Function in Individualizing Thoracic Radiotherapy

Purpose: Heterogeneity of lungtissue density and function is a hallmark of pathologic changes in chronic obstructive pulmonary disease (COPD). However, the standard risk assessment approaches, based on dose‐volume histograms (DVH), do not currently use the functional information in evaluating pulmonary tolerance to radiation therapy. We investigated the utility of weighting of dose distributions by surrogate metrics of the lung function (parenchyma density, ventilation distribution) as complementary sources of information for assessing the risk of complications, and for further individualizing of thoracic radiation therapy.Methods: The tissue density and the distribution of ventilatory activity were estimated from respiration‐correlated CT scans of 19 patients. Dose distributions from clinical IMRT (N=17) and proton (N=2) therapy plans were reevaluated by applying importance weighting to separate 1‐cc volume elements in the lung, accordingly with their estimated relative functional load. The histogram metrics: mean lungdose (MLD), share of the 5‐Gy isodose (V5), etc., were compared between various dose‐weighting methods. Regions characterized by high ventilatory activity were segmented, and research IMRT plans were optimized with objectives aiming to maximize sparing of lung function. Results: Substantial differences between the metrics of DVH and ventilation‐weighted histograms were observed, e.g., change of over 5% in MLD in 8 patients, relative increase of over 10% in V20 in 3 patients out of 19. The correlation between the density‐ and ventilation‐weighted metrics was insignificant. The use of additional optimization constraints for highly‐ventilated lung subvolumes allowed for a reduction in the ventilation‐weighted MLD, without compromising the target coverage, or causing deterioration in the standard DVH. Conclusions: Elevated values of ventilation‐weighted MLD may indicate the increased risk of complications in patients with COPD. The use of ventilation distribution maps for selection of beam angles, and definition of optimization constraints for functional avoidance, can potentially reduce the risk, without compromising the therapy efficiency.
Low temperature protocol for efficient transformation of Mycobacterium smegmatis spheroplasts

Spheroplasts ofMycobacterium smegmatis LM15, strain 607, were prepared by a combined treatment with glycine and lysozyme. The spheroplasts were tested for ability to take up and express purified mycobacteriophage DNA. Exposure of 1.0×108 to 1.0×109 spheroplasts to saturing DNA (1 μg) for 15 min at 5°C resulted in a transfection efficiency of approximately 0.009%. The transfer of the β-lactamase marker with DNA purified from strain LM15 to spheroplasts of a β-lactamase-negative mutant, strain LM144, was achieved. The DNA-treated cultures, after reversion to the bacillary form, contained 20-fold more penicillinresistant cells than the nontreated control culture. Approximately 80% of the penicillin-resistant colonies from the DNA-treated cells were positive for β-lactamase. Cell-free extracts of penicillin-resistant transformants contained β-lactamase activity that ranged from 0.046 to 0.134 μmol of benzylpencillin hydrolyzed/min per mg protein. This low temperature procedure is recommended for high efficiency transformation ofM. smegmatis.