cssi/SciSciGPT-SciSciNet huggingface dataset:
Role of Golgi apparatus in the formation of melanin granules in human malignant melanoma.

Human malignant melanoma cells were examined by electron microscopy in order to determine the site of formation of the melanin granules. Evidence was obtained which indicated that the smallest melanin granules first appeared in the vesicles of the Golgi apparatus. Intermediate stages between small Golgi vesicles and mature melanin granules were also frequently observed. The observations generally provide support for the concept of the Golgi apparatus as the site of origin of the melanin granules in this human cell type.
Making the Right Hires And Helping Them Succeed

Carol Wyatt, MPA, CBET, is a manager of biomedical engineering at Baylor Health Care System in Plano, TX. E-mail: CarolWy@BaylorHealth.edu Have you ever had the opportunity to speak to biomed students and have them ask you, “What can I do to prepare myself to work in a hospital environment?” As you think about their question, you realize the little things that are common and routine to us can be a source of anxiety for a new hire. What elevators should I use? Can I go into a patient’s room? What if the patient talks to me or, worse, asks for help? Do I have to talk to the nurses, doctors, or other techs? What if I break something? Just tell those eager biomed students what you would expect from them in those situations. As the hiring manager, you hold the key to successfully acclimating a new customer service-oriented biomedical equipment technician to your team and your organization. Biomeds are no longer just repair techs. They are ambassadors of the biomed department and must be able to interact with the directors, managers, and even the C-Suite. The biomedical field is a customer service field with a technical skill set requirement.
Active perception of material and shape by a walking robot

A legged robot can use its legs for more than locomotion. It can use them to identify the material properties and shape of the terrain it traverses. The author formulates active perception techniques based on force/torque sensing to identify terrain stiffness and surface friction, and present first results in applying the techniques to characterize terraine traversability. The author also describes purposeful contact sensing to update geometric terrain maps in a process that might be called 'shape from kicking'. >
Humans and animals: Relationships and boundaries

McCorkle, Constance M., Evelyn Mathias and Tjaart W. Schillhorn van Veen, eds. Ethnoveterinary Research and Development. London: Intermediate Technology Publications, 1996. vi + 338 pp. including collected references and index. $24.95 paper. Schwartz, Marion. A History of Dogs in the Early Americas. New Haven: Yale University Press, 1997. xvii + 233 pp. including appendices, notes, references, and index. $27.50 cloth. Shepard, Paul. The Others: How Animals Made Us Human. Washington, DC: Island Press, 1996. x + 374 pp. including collected references and index. $24.95 paper.
Orthogonal orientations for solvation of polymer molecules in smectic solvents

We explore the solvation of single conjugated polymer molecules in a smectic liquid crystal using single molecule spectroscopy. We find evidence for two distinct orientations for solvation: the majority of polymers are narrowly orientated parallel to the nematic director, as expected, but, unexpectedly, a second population is aligned perpendicular to the director. These molecules reside in the gaps between the layers. This latter type of solvation has not been previously observed and is not expected when the density variation along the director is sinusoidal.
Determination of atrazine in water at low- and sub-parts-per-trillion levels by using solid-phase extraction and gas chromatography/high-resolution mass spectrometry

A capillary column gas chromatography/high-resolution mass spectrometry (GC/HRMS) method was developed determine atrazine in water at low- and sub-parts-per-trillon (ppt) levels. The method fills a need when the detection limits of routine GC, GC/MS, and high-performance liquid chromatography (HPLC) are inadequate for studies to evaluate transport and fate of herbicides in deep ground water systems. Atrazine and the added internal standard [ 13 C 3 ]atrazine were extracted from water samples by solid-phase extraction using a C 18 bonded silica cartbridge
Current generation in microbial electrolysis cells with addition of amorphous ferric hydroxide, Tween 80, or DNA

Abstract Iron-oxide nanoparticles and the Tween 80 have previously been shown to improve power generation in microbial fuel cells (MFCs), presumably by improving electron transfer from the bacteria to the anode. We examined whether several chemicals would affect current production in single-chamber microbial electrolysis cells (MECs), where hydrogen gas is produced at the cathode, using mixed cultures and Geobacter sulfurreducens. Tween 80 did not increase the current. Fe(OH)3 addition increased the maximum current density of both the mixed cultures (from 6.1 ± 0.9 A/m2 to 8.8 ± 0.3 A/m2) and pure cultures (from 4.8 ± 0.5 A/m2 to 7.4 ± 1.1 A/m2). Improved current production was sustained even after iron was no longer added to the medium. It was demonstrated that increased current resulted from improved cathode performance. Analysis using electrochemical impedance spectroscopy (EIS) showed that the iron primarily reduced the diffusion resistances of the cathodes, and scanning electron microscopy (SEM) images showed the formation of highly porous structures on the cathode. The addition of DNA also did not improve MEC or MFC performance. These results demonstrated that among these treatments only Fe(OH)3 addition was a viable method for enhancing current densities in MECs, primarily by improving cathode performance.
Multilayer Rigid‐flex Printed Wiring Design Considerations

Rigid‐flex printed wiring constructed in different multilayer configurations and with varying features is discussed. Materials used in rigid‐flex construction have widely varying properties which cause processing difficulties and thermal stress related problems which can be minimised by proper construction features. Examples of failure mechanisms due to improper construction or material usage are given. Design considerations which will avoid construction related defects are summarised.
Quantitative analysis of N-terminal valine peptide adducts specific for 1,2-epoxy-3-butene

Butadiene (BD) metabolism shows gender, species and concentration dependency, making the extrapolation of animal results to humans complex. BD is metabolized mainly by cytochrome P450 2E1 to three epoxides, 1,2-epoxy-3-butene (EB), 1,2;3,4diepoxybutane (DEB) and 1,2-epoxy-butanediol (EB-diol). For accurate risk assessment it is important to elucidate species differences in the internal formation of the individual epoxides in order to assign the relative risks associated with their different mutagenic potencies. Analysis of N-terminal globin adducts is a common approach for monitoring the internal formation of BD derived epoxides. Our long term strategy is to develop an LC–MS/MS method for simultaneous detection of all three BD hemoglobin adducts. This approach is modeled after the recently reported immunoaffinity LC–MS/MS method for the cyclic N,N-(2,3-dihydroxy-1,4-butadyil)-valine (pyr-Val, derived from DEB). We report herein the analysis of the EB-derived 2-hydroxyl3-butenyl-valine peptide (HB-Val). The procedure utilizes trypsin hydrolysis of globin and immunoaffinity (IA) purification of alkylated heptapeptides. Quantitation is based on LC–MS/MS monitoring of the transition from the singly charged molecular ion of HB-Val (1–7) to the a1 fragment. Human HB-Val (1–11) was synthesized and used for antibody production. As internal standard, the labeled rat-[ 13 C5 15 N]-Val (1–11) was prepared through direct alkylation of the corresponding peptide with EB. Standards were characterized and quantified by LC–MS/MS and LC–UV. The method was validated with different amounts of human HB-Val standard. The recovery was >75% and coefficient of variation <25%. The LOQ was set to 100 fmol/injection. For a proof of principal experiment, globin samples from male and female rats exposed to 1000 ppm BD for 90 days were analyzed. The amounts of HB-Val present were 268.2 ± 56 and 350 ± 70 pmol/g (mean ± S.D.) for males and females, respectively. No HB-Val was detected in controls. These data are much lower compared to previously reported values measured by GC–MS/MS. The difference may be due higher specificity of the LC–MS/MS method to the N-terminal peptide from the -chain versus derivatization of both - and -chain by Edman degradation, and possible instability of HB-Val adducts during long term storage (about 10 years) between the analyses. These differences will be resolved by examining recently collected samples, using the same internal standard for parallel analysis by GC–MS/MS and LC–MS/MS. Based on our experience with pyr-Val adduct assay we anticipate that this assay will be suitable for evaluation of HB-Val in multiple species. © 2006 Elsevier Ireland Ltd. All rights reserved.
Learner continuums and speech communities 1

Abstract A serious problem for those analyzing the linguistic dimensions of bilingual communities (as all others) is distinguishing individual from social phenomena. In this paper I present a method for analyzing the acquisition‐like patterns in the English consonants used by Spanish‐English bilinguals. This method is based on work by Bickerton (1973) and Gatbonton‐Segalowitz (1975) and allows a clear view of both individual and group. The analysis shows that there is a continuum of use of the standard English consonants not occurring in Spanish in both individual and social use. It also shows style shifting of a rather different sort than that usually delineated in sociolinguistic analyses. In addition, I argue 1) that a definition of speech community must be broad enough to encompass communities such as the one discussed, even though many speakers may show a variety of acquisition‐like forms; 2) that different sorts of varieties and communities may require different analytical techniques.
Household technology adoption, use, and impacts: Past, present, and future

Since the 1980s, researchers have been studying the phenomenon associated with technology being diffused to the household. In this paper, three themes in that stream of research, specifically adoption, use, and impacts, are explored. Key studies from prior research within each theme are discussed and directions for future research are offered. The directions for future research range from investigating adoption issues associated with the digital divide to understanding the impacts of new technology and social networking sites on individuals and families. The evolving nature of the technology continues to offer interesting research directions and challenges, with the study of unintended consequences of technology use presenting, perhaps, the greatest opportunities.
Effect of nickel and nitrogen on void formation in ion bombarded vanadium

Abstract The objective of this study is to determine how both substitutional and interstitial solutes affect void formation in vanadium. Samples of high purity vanadium have been doped with 1% to 8%; nickel, or with 1% nitrogen and irradiated with 14 MeV Cu ions to dose levels between 1 and 10 dpa at 6 × 10 −4 dpa / sec . Swelling is observed at temperatures ranging from 450°C to 650°C in high purity vanadium at 2.5 dpa. The peak swelling temperature at this dose level is 550°C. The addition of >2%; N1 to the high purity vanadium completely suppressed void formation at temperatures between 350°C and 650°C. Samples doped with 1% Ni exhibited extremely low void densities. In samples irradiated at 450°C, 550°C and 650°C nitrogen doping reduced the void density. This effect resulted in a generally decreased level of swelling in the V-1%N samples.
Enhancing bacterial transport for bioaugmentation of aquifers using low ionic strength solutions and surfactants

Abstract The transport of bacteria in contaminated aquifers over a distance of only one meter can require tens to thousands of unsuccessful collisions of bacteria with soil grains. Previous work has shown that low ionic strength (IS) solutions and the nonionic surfactant Tween 20 can reduce bacterial adhesion to ultraclean surfaces such as glass and quartz porous media. In this study, we examined whether these results could be generalized to soils and to other surfactants, by measuring the retention of two species of radiolabeled microbes over short (1 cm) distances in soil minicolumns. Calculations were also made, using the clean-bed filtration theory, to evaluate if bacterial transport distances are sufficient for bioagumentation to occur over a large region of the subsurface. Collision efficiencies were expressed using the filtration model in terms of the sticking coefficient, α, defined as the fraction of collisions that are successful. In glass bead columns, α's for monoclonal populations were reduced from α=0.19 (Alcaligenes paradoxus) and α=0.01 (CD1), to α 1 m. For A. paradoxus, α was reduced using a low ionic strength solution from 0.72 to 0.083 for the Arizona soil and from 1.7 to 0.2 for the Ringold soil; for CD1, α was reduced from 0.57 to 0.09 for the Ringold soil. Based on the soil grain diameters of these soils (127 μm, Arizona soil; 224 μm, Ringold soil), α's in this range will permit transport distances (defined as 99.9% reduction in cell concentration) of ∼1 m (U=10 m/d, 10°C) which may be sufficient for creating small, bioactive zones. However, in order to increase bacterial transport over distances >1 m, methods other than simple solution chemistry changes will be needed to enhance aquifer bioaugmentation operations.
Five strategies for overcoming obviousness

The author explained the various office actions that you are likely to see a patent examiner make (under legal sections 101-103 and 112) and briefly noted some other parts of the legal code that you are unlikely to encounter (legal sections 104, 105, and 113-122). In addition, the author mentioned the possibility of the examiner filing a restriction on your patent application. The two remaining sections, 102 and 103, address novelty and obviousness, respectively. Under section 102, the examiner cites a single reference to prior art that he claims is the same as your invention. That is, he makes the claim that your invention is not novel (new). This is usually cut and dried $he is either right, or he has misunderstood at least one of the inventions. Section 103 leaves you more wiggle room to argue, since it pertains to the murky area of obviousness. In a 103, the examiner cites not just one, but two or more references and claims two things: that combining the inventions in those multiple references will produce your invention; and that conceiving such a combination is obvious. In this column, the author explains five distinct dimensions in which you can argue to overcome a section 103 rejection. You may choose to argue in multiple dimensions, but if you do, make it clear at all times which dimension you are arguing, or your argument will be confusing
Mental Health Professionals' Contact With Family Members of People With Psychiatric Disabilities

Seventy-three community mental health professionals described their contact with family members of people with psychiatric disabilities. Survey questions asked about contact frequency, patterns of contact, and barriers to contact with families. A multiple regression model analyzed facilitators of increased family contact. Professionals reported a median of 2 family contact hours per week. Professionals who served children reported more family contact. Family members most often initiated telephone contact, especially parents, spouses, and siblings. Most frequent activities included listening, accessing information, and helping with resources and coping. Formal family-inclusive interventions were infrequent. Time was the most frequently reported barrier. Serving children and increased consumer contact predicted increased family contact time. Recommendations are offered for family-inclusive mental health practice.
Mammalian bite wounds

Clinical data were collected prospectively from a series of 160 patients presenting with mammalian bite wounds. Anaerobic and aerobic cultures were prepared from sterile swabs placed in 65 bite wounds prior to cleansing. Infection was noted in 11 of 22 cat bites, six of 37 human bites, three of 80 dog bites, and in none of the 21 bites caused by other mammals. Pasteurella multocida was recovered from six infected cat and dog bites, all of which developed infection within 24 hours of injury. Staphylococcus aureus and Streptococcus viridans were the principal pathogens isolated from the remaining infected cat, dog, and human bites. Infection most commonly followed puncture wounds caused by cats (10/19) and lacerations into subcutaneous tissue of the hand caused by humans (4/17). None of the 10 sutured wounds became infected. All infected bite wounds responded to antibiotic therapy. No conclusions regarding the value of prophylactic antibiotics could be made.
Activity and Inhibition of Polyphenol Oxidase in Extracts of Bran and Other Milling Fractions from a Variety of Wheat Cultivars

ABSTRACT Studies were conducted to compare polyphenol oxidase (PPO) specific activities in various milling fractions of a variety of wheat cultivars and determine the levels of activities in a number of cultivars from different localities and harvesting seasons. Substrate specificities were also investigated. Bran was singled out as the richest source of PPO activity, which may also influence the activity in the other milling fractions that are known to have some proportion of bran content. We showed by gel electrophoresis and spectrophotometrically that the protein responsible for PPO activity apparently exists as a single isoform in bran and that the observed enzyme activity is likely to be a tyrosinase type, not a laccase or peroxidase. The specific activity was not significantly different between the reduction shorts and break shorts from the same cultivar, indicating a similar level of bran contamination in these fractions. Very low levels of PPO activity were recorded in the flour of all cultivars s...
High-Performance Computing for Fluid Flow and Heat Transfer

The use of computers in heat transfer and fluid flow has become so commonplace today that no one would consider working in either field without some knowledge of computing. Problems are now being solved on a daily basis that even a few years ago were considered intractable. While we once thought that a problem with a few million nodes was huge a few years ago, researchers are now addressing problems with over 100 million nodes. At such levels of detail, one can begin to model processes at the micro level of physics. When researchers are able to quickly analyze these gigantic data sets and can generate insightful graphical displays, the understanding of fundamental processes and governing relations will escalate tremendously.Copyright © 2002 by ASME
Stored swine manure and swine faeces as reservoirs of antibiotic resistance genes

Inclusion of low levels of antibiotics in the feed of domestic food animals promotes improved growth, animal performance and overall health benefits. However, this practice has come under scrutiny due to concerns over such feeding on bacterial antibiotic resistance (AR) and potential impact on human health. There is a paucity of data on the types and levels of AR genes that may be present in agricultural practices. Using PCR detection of AR genes, this study demonstrates that both stored swine manure and swine faeces harbour a variety of AR genes, and bacterial members of these communities contain genes that may move between micro-organisms. Thus, both ecosystems may serve as reservoirs of AR genes.
Blocking Pairs of Polyhedra Arising from Network Flows

A study is made of blocking pairs of polyhedra (blocking pairs of matrices) that arise in (or can be transformed into) a network flow context. For example, the blocking polyhedron of the polyhedron generated by all integral feasible flows in a capacity-constrained supply-demand network (where all the data are integral) is explicitly determined, and a simple algorithm is described for solving the associated integral packing problem. Applications of these results to k-ways in directed graphs, to (0, 1)-matrices with prescribed row and column sums, and to flow arborescences are described.
Second method of Liapunov and Routh's canonical form

Abstract In this paper the equivalence between Liapunov's Second Method and the Routh-Hurwitz Criterion for Linear Systems is established. A transformation matrix Q is developed which transforms the system matrix A into a special matrix R called a Routh Canonical matrix. The elements of R matrix are closely related to the elements in the first column of Routh's arrays. The conditions of stability on R matrix from Liapunov's Second Method are the same as the Routh-Hurwitz Conditions. The treatment is extended to nonlinear systems. As a result of this transformation, the linear terms are automatically removed from further consideration and only the nonlinear terms remain. Method of analysis is explained with the help of examples.
Monitoring the Weibull shape parameter by control charts for the sample range

In this paper, we propose control charts for monitoring changes in the Weibull shape parameter β. These charts are based on the range of a random sample from the smallest extreme value distribution. The control chart limits depend only on the sample size, the desired stable average run length (ARL), and the stable value of β. We derive control limits for both one- and two-sided control charts. They are unbiased with respect to the ARL. We discuss sample size requirements if the stable value of βis estimated from past data. The proposed method is applied to data on the breaking strengths of carbon fibers. We recommend one-sided charts for detecting specific changes in βbecause they are expected to signal out-of-control sooner than the two-sided charts. Copyright © 2010 John Wiley & Sons, Ltd.
Stein's Method and Descents after Riffle Shuffles

Abstract. Berestycki and Durrett used techniques from random graph theory to prove that the distance to the identity after iterating the random transposition shuffle undergoes a transition from Poisson to normal behavior. This paper establishes an analogous result for distance after iterates of riffle shuffles or iterates of riffle shuffles and cuts. The analysis uses different tools: Stein's method and generating functions. A useful technique which emerges is that of making a problem more tractable by adding extra symmetry, then using Stein's method to exploit the symmetry in the modified problem, and from this deducing information about the original problem.
Characterizations of subnormal matrices

Abstract Suppose that is said to be subnormal if there exist matrices X and Y such that is normal. We develop characterizations of subnormal matrices as well as constructive techniques for normal extensions. For example, we show that geometrical properties of certain subsets of the spectrum of A determine if normal extensions exist. Our results add to as well as generalize those of an earlier paper.
Streptovaricins inhibit Focus Formation by MSV (MLV) Complex

We recently reported that the streptovaricins inhibit the reaction by which DNA is transcribed from the RNA template resident in murine leukaemia virions (MLV)1. The reports2, 3 which first indicated that this DNA polymerase is present in oncogenic RNA viruses have been confirmed and extended4–8. The enzyme provides a mechanism whereby an RNA virus can insert stable genetic information into a host chromosome. Gallo and co-workers described an RNA dependent DNA polymerase in lymphoblastic leukaemic cells which was inhibited by N-demethylrifampicin9 and this antibiotic, together with a number of other rifamycin derivatives, also inhibited the oncogenic viral DNA polymerase10. Like the streptovaricins, the rifamycins are ansa macrolide antibiotics (Fig. 1).
Laparoscopic mesh cruroplasty for large paraesophageal hernias.

Background: Previous studies have shown that surgical repair of paraesophageal hernias is associated with a high recurrence rate, especially when a laparoscopic approach is used. Anatomic recurrence due to crura breakdown is a primary etiology, which has led us to employ prosthetic mesh reinforcement of large hiatal defects (> 5 cm) since 1996. We discuss the evolution of this approach and describe our current technique with limited outcomes in 52 consecutive patients during a 5-year period. Methods: There were 31 males and 21 females, with a mean age of 57 years (range, 32–77 years) with symptomatic reflux and endoscopic or radiologic evidence of a large paraesophageal hernia. Utilizing a laparoscopic approach, the contents of the sac were reduced and the crura approximated with permanent interrupted sutures and a prosthetic mesh was secured over the repair as an on-lay reinforcement buttress. A Nissen (42) or Tilley (9) fundoplication was performed in all but 1 patient, and 18 patients (34%) required a wedge collis gastroplasty. Fifteen patients (28%) had a previous unsuccessful antireflux operation. Results: There was no perioperative morbidity or mortality. Follow-up averaged 25 months (range, 7–60 months). Postoperative gastroscopy or barium swallow have been performed in 27 patients to date, with 11 experiencing foregut symptoms. There has been 1 recurrence (1.9%) and no prosthetic erosion. Conclusion: Early results suggest that prosthetic mesh cruroplasty may be effective in reducing recurrence after laparoscopic repair of large paraesophageal hernias, but long-term follow-up is required in all patients to determine the true incidence of anatomic recurrence and prosthetic erosion.
Development of Ox-Coyote Cycle of Sarcocystis cruzi†

The ox-coyote cycle of Sarcocystis cruzi was studied by killing 38 calves between 4 and 153 days postinoculation (DPI) with 55 × 103-5 × 108 sporocysts from the intestines of coyotes. At 4 DPI, a zoite was found within the lumen of a mesenteric lymph node artery. At 7 DPI, zoites were found in mononuclear cells and in endothelial cells in mesenteric arteries. First generation meronts (41.0 × 17.5 μm in diameter) occurred 7–26 DPI in mesenteric lymph nodes. At 19–46 DPI, second generation meronts occurred in kidneys, muscles, and other tissues: renal meronts were 19.6 × 11.0 μm, and intramuscular meronts were 25.0 × 11.1 μm. Merozoites were found in the peripheral blood 17 DPI and later at 24–46 DPI. They divided by endodyogeny in mononuclear cells. Sarcocysts were seen first in the heart at 45 DPI and contained one or two metrocytes. At 55 DPI, sarcocysts containing only metrocytes were found in striated muscles, heart, and in smooth muscles of the urinary bladder, rumen, omasum, abomasum, and small intestine. At 67, 87, 112, and 153 DPI, sarcocysts were found only in striated muscles and in the heart. At 67 DPI, sarcocysts were up to 360 μm long. They contained only metrocytes and were not infective to the dog. At 86 DPI, sarcocysts contained mostly bradyzoites, a few metrocytes, and were infective to a coyote. The thin-walled sarcocysts grew to a maximum length of 800 μm and contained bradyzoites that were 10.9 × 3.0 μm. At 90 DPI, two mature sarcocysts were found in 2 of 73 sections of brain and spinal cord; hundreds of sarcocysts were present in sections of tongue and heart of this calf. Gametogony occurred in the small intestine of the coyote. Macro-and microgamonts were found in goblet cells of the small intestines of coyotes 6 h after the ingestion of infected meat. Microgamonts were few and contained 3–11 slender gametes. Oocysts were seen at 12 h and sporulation was completed 9 DPI. The prepatent period in the coyote was 8 days. The ox-coyote cycle is compared with ox-dog cycle.
Computation of gas-phase enthalpies of formation with chemical accuracy: The curious case of 3-nitroaniline

Abstract Using a variety of density functional, post-Hartree–Fock and composite methods, in conjunction with extended basis sets, and a homodesmotic reaction, we conservatively propose a gas-phase enthalpy of formation for 3-nitroaniline of 17 ± 1 kcal mol −1 , a value that significantly differs from experimental values suggested in compendia of thermochemical data. Assuming that the reported experimental solid-state enthalpy of formation by Nishiyama et al. is reliable at 8.2 ± 0.3 kcal mol −1 , an enthalpy of sublimation for 3-nitroaniline of 25 ± 1 kcal mol −1 is estimated.
SAR image invariants from 3D scattering centers

Synthetic Aperture Radar (SAR) sensors have many advantages over electro-optical sensors (EO) for target recognition applications, such as range-independent resolution and superior poor weather performance. However, the relative unavailability of SAR data to the basic research community has retarded analysis of the fundamental invariant properties of SAR sensors relative to the extensive invariant literature for EO, and in particular photographic sensors. Prior work that was reported at this conference has developed the theory of SAR invariants based on the radar scattering center concept and provided several examples of invariant configurations of SAR scatterers from measured and synthetic SAR image data. This paper will show that invariant scattering configurations can be extracted from predicted 3D data scatterer data and used to predict invariant features in measured SAR image data.
Solving Euclidean minimal spanning tree problem using a new meta-heuristic approach: Imperialist Competitive algorithm (ICA)

The minimum spanning tree (MST) problem has numerous applications in design of communication, computer and transportation networks. This paper proposes an application of a new meta-heuristic called Imperialist Competitive algorithm (ICA) for solving a special case of MST defined on a Euclidean plane, called the Euclidean minimum spanning tree (EMST) problem. ICA is inspired by human's socio-political evolution. The solution quality and speed of the proposed are verified by numerical examples compared to a commercial optimization solver.
A Genetic Strategy for Graded and Dynamic Control of Cell-Matrix Mechanobiology

Mechanical interactions between cells and the surrounding extracellular matrix, such as adhesion, contraction, and force transduction, play a central role in many fundamental cell behaviors, including proliferation, cell death, and motility. The ability to precisely manipulate the intracellular machinery that regulates these interactions could therefore provide a powerful tool for controlling the mechanical properties of living cells and could also allow us to re-engineer how cells sense and respond to mechanical stimuli in their microenvironment, which would be particularly useful for tissue engineering and cellular technologies where cells are interfaced with synthetic microenvironments. Towards this goal, we have genetically engineered stable cell lines in which we can precisely and dynamically alter the mechanobiological behavior of living cells by varying the activity of signal transduction proteins, such as RhoA GTPase, using constitutively active and dominant negative mutants under the control of a tetracycline-repressible promoter. Through a variety of imaging and biophysical techniques, including atomic force microscopy and traction force microscopy, we have demonstrated graded and dynamic control over cytoskeletal architecture, cell shape and spreading, contractility, and cellular stiffness. In addition, using glioblastoma multiforme as a model system, we show how these cell lines can be used to study the effects of altered cellular mechanical properties on cancer cell motility and invasion.
Some calcium and lysosome antagonists inhibit 3H-spirerone binding to the porcine anterior pituitary

The dopamine antagonist 3H-spiperone binds to dopamine receptors in crude membrane preparations of the porcine anterior pituitary. In competition studies, several calcium channel antagonists (bepridil, D600 and verapamil) and a lysosomal enzyme inhibitor (chloroquine) displaced spiperone binding in a dose related manner. Because dopamine receptor activity modulates prolactin release from the anterior pituitary, it is suggested that the previously observed effects of some of these agents on prolactin release or storage may have been initiated at the level of the dopamine receptor or through physical modifications of the plasma membrane rather than the calcium channel or lysosome.
Visceral vessel erosion associated with pancreatitis. Case reports and a review of the literature.

• Visceral artery erosion is an uncommon but disasterous complication of pancreatitis. When gastrointestinal bleeding or severe intra-abdominal hemorrhage is associated with pancreatitis and the usual sources of bleeding are not detected by endoscopy or barium studies, erosion of a visceral vessel should be suspected. We present nine cases and an additional 44 cases from previous reports are reviewed. A palpable abdominal mass was present in 59% of the patients; however, a pseudocyst was present in 78%. Arteriography was performed in 15 patients and the source of bleeding was evident in 14. The splenic artery was the most common site of bleeding, although the other branches of the celiac axis and the middle colic artery have been involved. Successful treatment consisted of ligation of the bleeding vessel and, if present, drainage of the pseudocyst. Depending on the location of the vessel and the pseudocyst, major resections may be necessary. When bleeding and the pancreatic inflammatory process involved the colon, ligation of the bleeding site, drainage of the area, and colostomy was the most successful form of treatment. ( Arch Surg 113:1438-1440, 1978)
A prophet to modern medicine: Ernest Amory Codman.

Caitlin Hicks and Martin Makary describe the life of the pioneer of healthcare registries Remarkably, the outcomes of medical procedures are rarely tracked today. As a result, establishing the best medical treatment can be difficult. Trials to establish best practices are often isolated, underpowered, and lag behind widespread adoption. Moreover, standardized methods to capture complications are lacking for most interventions. This problem is as old as medicine itself. But one man boldly sought to challenge the status quo and tackle the problem—Ernest Amory Codman (fig 1⇓). Codman was a surgeon who believed that by prospectively tracking outcomes we can learn from our patients and advance the field of medicine quickly. Codman was a scientist of quality. He helped usher in the concept of the regular morbidity and mortality conference and started the first national registry in American healthcare. Given the challenges of medicine today—endemic rates of medical errors, wide variations in quality, and an expanding cost crisis—many physicians are calling for Codman’s basic tenants to be re-visited and applied. Fig 1 Ernest Amory Codman, reproduced with permission from Boston Medical Library in the Francis A Countway Library of Medicine Born in 1869, Ernest Amory Codman was a natural academic. He won the prestigious founder’s medal at St Mark’s School as a high school senior and graduated with honors from Harvard College in 1891.1 He undertook his medical education at Harvard Medical School, where he met Harvey Cushing. In 1895, Codman graduated from medical school and joined the staff at Massachusetts General Hospital as an assistant in anatomy, where he became the apprentice of the chief of surgical services, Dr Francis Harrington. In 1900, he was appointed assistant in clinical operative surgery. Through his work with Dr Walter Bradford Cannon, among others, Codman developed strong x ray imaging skills, …
Changing optical axis due to reactor operation

Abstract During reactor operation, the neutron flux distribution is modified by the reactor control mechanisms and in the case of the reactor at the National Institute of Standards and Technology, this is determined by the angular position of the Cd shim arms and the vertical position of an Al regulating rod. The changing flux distribution results in a change in the optical axis of neutron beams, whose view is a fixed position within the reactor core. The changing optical axis results in two noticeable image artifacts: poor registration between images of a static object taken at different times and a change in the shape of the flat field intensity. These two effects were measured during the first four days of reactor operation. Both measurements show correlation with the reactor control mechanisms, with combined correlation coefficients during the first two days after reactor startup approaching 1. The change in the edge position is well below the image spatial resolution, and has more uncertainty associated with it. However, the change in the flat-field shape demonstrates a clear correlation with both shim arm angle and regulating rod position.
Collaboration and Communication in the Online Classroom through a Brain-Based Approach

Utilizing brain-based learning strategies in the classroom encourages the creation of learning environments that are inviting, engaging, and meaningful. Information and communication technologies used in online classes can be enhanced and made more meaningful for students by applying a brain-based approach. This paper examines the use of brain-based learning in an online environment to build an inviting and collaborative cultural experience for learners. A brain-based model is explored to illustrate effective teaching strategies that can be implemented in an online learning environment. Empirical research and analysis are presented in a research study along with a theoretical evaluation of how incorporating brain-based strategies in online learning can positively affect overall student development and online culture.
On a generalization of the matrix and scalar Riccati equation

Abstract The usual Matrix Riccati equation can be related to the transport of a beam of particles through a medium of finite length with conservative type of interactions (R. Bellman, S. Ueno, and R. Vasudevan, On the matrix Riccati equation of transport processes, University of Southern California Technical Report No. 72-13). Varying the physical picture of the interactions in the medium, we arrive at extensions of the Riccati equations with higher order nonlinear terms. Using the physical picture to guide our intuition, we achieve a linearization of these generalized Riccati equations in this paper, and this procedure will assist numerical computation of the solution of such nonlinear equations in a substantial manner.
Orbital YORP and asteroid orbit evolution, with application to Apophis

Abstract Photon thrust from shape alone can produce quasi-secular changes in an asteroid's orbital elements. An asteroid in an elliptical orbit with a north–south shape asymmetry can steadily alter its elements over timescales longer than one orbital trip about the Sun. This thrust, called here orbital YORP (YORP = Yarkovsky–O'Keefe–Radzievskii–Paddack), operates even in the absence of thermal inertia, which the Yarkovsky effects require. However, unlike the Yarkovsky effects, which produce secular orbital changes over millions or billions of years, the change in an asteroid's orbital elements from orbital YORP operates only over the precession timescale of the orbit or of the asteroid's spin axis; this is generally only thousands or tens of thousands of years. Thus while the orbital YORP timescale is too short for an asteroid to secularly journey very far, it is long enough to warrant investigation with respect to 99942 Apophis, which might conceivably impact the Earth in 2036. A near-maximal orbital YORP effect is found by assuming Apophis is without thermal inertia and is shaped like a hemisphere, with its spin axis lying in the orbital plane. With these assumptions orbital YORP can change its along-track position by up to ± 245 km , which is comparable to Yarkovsky effects. Though Apophis' shape, thermal properties, and spin axis orientation are currently unknown, the practical upper and lower limits are liable to be much less than the ± 245 km extremes. Even so, the uncertainty in position is still likely to be much larger than the ∼ 0.5 km “keyhole” Apophis must pass through during its close approach in 2029 in order to strike the Earth in 2036.
On the transition between a wetting film and a capillary meniscus

Abstract The shape of a horizontal meniscus which is influenced both by capillarity and by an adsorbed thin film is determined. An exact solution is obtained which clearly shows the features of a transition between a curved meniscus and an adsorbed film. The method of matched asymptotic expansions is used to elucidate many of the details of the transition layer, its horizontal thickness, and the question of apparent contact angle.
Comparing systems via stochastic simulation: an enhanced two-stage selection procedure

This paper discusses implementation of a two-stage procedure to determine the simulation run length for selecting the best of k designs. We purpose an Enhanced Two-Stage Selection (ETSS) procedure. The number of additional replications at the second stage for each design is determined by both the variances of the sample means and the differences of the sample means of alternative designs. We show that the ETSS procedure gives valid selections with significantly reduced simulation replications compared to Rinott's procedure. An experimental performance evaluation demonstrates the validity of the ETSS procedure.
Preparticipation cardiovascular screening among National Collegiate Athletic Association Division I Institutions

Background Sudden cardiac arrest is the leading cause of death in competitive athletes during sport, and screening strategies for the prevention of sudden cardiac death are debated. The purpose of this study was to assess the incorporation of routine non-invasive cardiovascular screening (NICS), such as ECG or echocardiography, in Division I collegiate preparticipation examinations. Methods Cross-sectional survey of current screening practices sent to the head athletic trainer of all National Collegiate Athletic Association (NCAA) Division I football programmes listed in the National Athletic Trainers’ Association directory. Results Seventy-four of 116 (64%) programmes responded. Thirty-five of 74 (47%) of responding schools have incorporated routine NICS testing. ECG is the primary modality for NICS in 31 (42%) of schools, and 17 (49%) also utilise echocardiography. Sixty-four per cent of the programmes that do NICS routinely screen their athletes only once as incoming freshmen. Of institutions that do not conduct NICS, American Heart Association guidelines against routine NICS and cost were the most common reasons reported. Conclusions While substantial debate exists regarding protocols for cardiovascular screening in athletes, nearly half of NCAA Division I football programmes in this study already incorporate NICS into their preparticipation screening programme. Additional research is needed to understand the impact of NICS in collegiate programmes.
Pulmonary Embolism Complicating Bariatric Surgery: Detailed Analysis of a Single Institution’s 24-Year Experience

Background Morbidly obese patients undergoing bariatric procedures are at risk for pulmonary embolism (PE). Because large series are required to analyze low-incidence complications, factors predictive of PE have not been clearly defined. Since 1992, short-course heparin prophylaxis, beginning immediately before operation, has been used in this center. Study design Prospective data on 3,861 patients undergoing bariatric procedures between 1980 and 2004 were queried. Factors analyzed included age, gender, body mass index, interval between procedure and PE, inpatient versus outpatient status, mortality, access method (open versus laparoscopic), and comorbidities. Results PE within 60 days of operation occurred in 33 patients (23 women, 10 men), for an incidence of 0.85%. No difference in incidence was noted between open (0.84%) and laparoscopic (0.88%) groups, nor did routine prophylaxis with heparin since 1992 decrease the incidence. The interval between procedure and PE was 13.2 ± 2.6 (mean ± SEM) days (open = 13.0 ± 3.0 days, laparoscopic 14.1 ± 6.49 days, p = 0.9). One-third of PEs occurred after hospital discharge. Pulmonary embolism–related mortality was 27%. A statistically greater body mass index was noted in PE patients compared with non-PE patients (57.2 ± 2.4 kg.m2 versus 49.9 ± 0.2 kg/m2, p Conclusions Data demonstrated persistence of PE risk in the anticoagulation, laparoscopic-access era at a rate similar to that in the preanticoagulation, open-access era. Because one-third of PEs occur after hospital discharge, consideration should be given to continuing anticoagulants longer and to adopting a more aggressive policy of inferior vena cava filter prophylaxis, particularly in patients with high body mass index, obese hyperventilation syndrome, and venous insufficiency.
Relationship between age, percentage body fat, fitness, and 24-hour growth hormone release in healthy young adults: Effects of gender

We investigated whether gender affects the physiological relationships between the release of GH and age, body composition, and levels of physical fitness in humans. We studied 32 eumenorrheic females (age = 31 +/- 5 yr) and 12 males (age = 27 +/- 5 yr). Significant gender differences were found for peak oxygen consumption [VO2 peak = 40.5 +/- 6.9 (females) vs. 50.1 +/- 11.6 (males) ml/kg.min-1, P < 0.05] and body composition [hydrostatic weighing, percentage body fat = 28.7 +/- 5.4 (females) vs. 18.1 +/- 9.8 (males), P < 0.05] but not for body mass index [BMI = 23.7 +/- 3.1 (females) vs. 24.0 +/- 3.3 (males)]. Blood samples were drawn every 10 min for 24 h from 0800 h to determine integrated serum GH concentration [2350 +/- 1260 (females) vs. 3110 +/- 1760 (males) microgram/L x min]; females were studied during the early follicular phase (days 4-5) of the menstrual cycle. In females, a significant relationship existed between 24-h integrated serum GH concentration and age (r = -0.35, P = 0.05) but not BMI (r = -0.19, P = 0.29); the relationship between 24-h integrated serum GH concentration and VO2 peak (r = 0.31, P = 0.08) and percentage body fat (r = 0.29, P = 0.11) approached significance. In males, significant relationships existed between 24-h integrated serum GH concentration and age (r = -0.79, P = 0.002), percentage body fat (r = -0.75, P = 0.005), and VO2 peak (r = 0.58, P = 0.05) but not between 24-h integrated serum GH concentration and BMI (r = -0.53, P = 0.08). Standardized regression coefficients revealed that for each SD change in age, BMI, percentage body fat, or VO2 peak the associated change in 24-h integrated serum GH concentration was 1.9-2.6 times greater in males than in females. We conclude that age, percentage body fat (but not BMI), and fitness are related to 24-h GH release in young adults and that these relationships are considerably stronger in males than females.
Dynamical transition in quasistatic fluid invasion in porous media.

Numerical simulations of capillary displacement in 2D porous media indicate a dynamical critical transition as the contact angle $\ensuremath{\theta}$ of the invading fluid varies. In the nonwetting limit ($\ensuremath{\theta}=180\ifmmode^\circ\else\textdegree\fi{}$), growth patterns are fractal as in the invasion percolation model. As $\ensuremath{\theta}$ decreases, cooperative smoothing mechanisms involving neighboring throats become important. The typical width of invading fingers appears to diverge at a critical angle which depends on porosity. Below this angle the fluid floods the system uniformly.