cssi/SciSciGPT-SciSciNet huggingface dataset:
A carbon-13 NMR comparative study of metal ion substitutions in human carbonic anhydrase I carboxymethylated at active-site Histidine-200

Human carbonic anhydrase I (EC 4.2.1.1), the low-activity isozyme, has a reactive active-site Histidine-200 that is known to be specifically modified at N tau with haloacetates. Using [1-13C]bromoacetate, we previously introduced a highly sensitive 13C NMR probe into the active site of the enzyme and studied the interaction of the carboxymethyl carboxylate with the active-site zinc, as well as the ionization properties of the carboxymethylated histidine-200 side chain. In the present work, these studies have been extended to metalloderivatives of the enzyme in which the intrinsic zinc has been replaced by Cd2+, Hg2+, and Co2+. In the former two metals, spin-1/2 isotopes (113Cd and 199Hg) in the absence of inhibitory halides were utilized to search for two-bond spin-spin couplings in the spectrum of the 13C-enriched carboxymethyl carboxylate under conditions where coordination exists in the Zn and Co derivatives. The absence of splittings and titration studies of the chemical shift of the resonance both established the absence of coordination. The pH dependence of the carboxylate, which reflects the ionization of the CmHis-200 ring, was observed in the presence and absence of bound inhibitors. Marked differences were seen among the four metalloderivatives in all these properties, suggesting great sensitivity of the active site to the nature of the metal inserted. The data suggest extreme caution in extrapolating results from metal ion substitution studies to the native zinc enzyme, and may reflect functional significance of this sensitivity in the catalysis.
Something to Talk About: Romantic Relationships M Organizational Settings

This article reviews the meager management and organizational behavior literature on romantic relationships in organizational settings. It demonstrates that workplace romance is a topic on which much theoretical and, more importantly, empirical research is needed. Workplace romances have important work-related implications for the two participants, coworkers, supervisors, and the organization as a whole. A research agenda and research propositions are offered to stimulate future scholarly interest in this area.
Plasma-enhanced chemical vapor deposition of zinc oxide at atmospheric pressure and low temperature

Abstract The plasma-enhanced chemical vapor deposition of aluminum-doped zinc oxide has been demonstrated for the first time at 800 Torr and under 250 °C. A film resistivity of 3 × 10 - 2 Ω cm and a transparency of 95% from 375 to 2500 nm was obtained for deposition at 20-mTorr diethylzinc, 1.0 Torr CO 2 , 799 Torr He, a TMAl/DEZn ratio of 1:100, 41 W / cm 3 RF power, and 225 °C. The average aluminum concentration in the ZnO film was 5.4 × 10 20 cm - 3 . It was found that, while the growth rate did not change with substrate temperature, both the resistivity and optical absorption coefficient declined with increasing temperature.
Terahertz radiation induced by subband-gap femtosecond optical excitation of GaAs

We have observed terahertz radiation induced by subband-gap femtosecond optical excitation from GaAs. We belive this is due to screening of the surface depletion field by virtual photocarriers (the inverse Franz-Keldysh effect).
Novel Pn Polymorph for Li2MnSiO4 and Its Electrochemical Activity As a Cathode Material in Li-Ion Batteries

We report on the synthesis and characterization of a new metastable polymorph of Li2MnSiO4 adopting the Pn space group, prepared by ion-exchange from Na2MnSiO4. Density-functional theory methods were used to predict the lattice parameters and atom positions of the new polymorph material and those of Na2MnSiO4 and LiNaMnSiO4, allowing their identification by X-ray diffraction profiles, as well as the comparison of the measured and calculated cell parameters. The electrochemical activity of this new polymorph as a cathode material for lithium ion batteries was evaluated in coin cells and compared to that of the thermodynamically stable Pmn21 polymorph of Li2MnSiO4, as well as LiNaMnSiO4 and Na2MnSiO4. Carbon coating, very vital to the electrochemical activity of the material, was added in situ to the material before ion-exchange because the metastable polymorph converts to the stable polymorph above 370 °C, as confirmed by differential scanning calorimetry scans. Both Li2MnSiO4 polymorphs display similar ch...
Image Segmentation Using Background Estimation

Segmentation algorithms that do not require preselected thresholds and are rapid and automatic for various applications are introduced. The approach is to track how the background graytone distribution varies throughout the image without a priori knowledge. Rectangular image regions are sampled to track background variations. Criteria based on statistical theory are used to determine the homogeneity of regions and to distinguish between background-homogeneous and object-homogeneous regions. The criteria include upper and lower bounds to account for practical situations which arise when the underlying assumptions become invalid. Segmentation is focused on non-homogeneous regions. The background graytone distribution throughout the image is estimated from regions where it is measurable. Knowledge of the local background distribution throughout the entire image is then used to preserve the local brightness relationship of object pixels to the background. Rather than simply mapping the graytone image into an object-background binary image, more information is retained by determining additional thresholds and mapping pixels into object brightness relative to background and into uncertainty. Image regions made up of uncertainty labelled pixels assist in identifying image regions that require further processing.
Fairness in landownership

Fairness in landownership is in most respects an extension of justice in the distribution of all forms of wealth. Some of the attention that philosophers and economists have focused on distributive justice generally, therefore, can be applied to landownership.' With a better understanding of ethical premises of distributive justice, landownership policies and the anlyses that support them will be better served. Tweeten recently stated his widely shared view of ethics in agricultural economic policy: "To judge morality, a norm is essential. I contend the appropriate norm is the dominant moral philosophy in America, utilitarianism 0 . based on what is variously termed wellbeing, satisfaction, quality of life, welfare, avoidance of pain, pursuit of happiness, or the greatest good for the greatest number of people" (p. 1). Tweeten seems to describe accurately the working premises of most agricultural economics research. That utilitarianism is the norm is correct; that utilitarianism is adequate as an ethical foundation for all or even most, policy-oriented research is doubtful. Utilitarianism is only one ethical perspective, and exclusive adherence to it for research or policy may not be desirable. Alternatives or modifications are worth exploring. Rawls and Rescher provide useful starting points. Their notions of fairness and distributive justice seem to remain, after substantial examination and time, at the core of what economists have labeled equity or equitability issues (Thurow, Vickrey). As a minimum, they provide an alternative to unquestioning acceptance of traditional utilitarianism in economic policy. Mill refined and extended Bentham's utilitarianism to form the foundations of modern economics (Warnock, p. 256-78). Mill's utilitarianism suggested a substance, utility, toward which economic analysis could be directed. Mill emphasized that ends are what are conceived as desirable but "that questions of ultimate ends do not admit of proof. ... Questions about ends are, in other words, questions about what things are desirable. The utilitarian doctrine is, that happiness is desirable, and the only thing desirable . . ." (Warnock, p. 288). Utilitarianism is significant in economics for (a) its dependence on happiness and (b) its consequentialist emphasis on ends. A concept of utility based on happiness has a certain quality of intuitive appeal, but a moment's reflection shows that either happiness must be defined so broadly as to be meaningless or other bases for utility such as truth, charity, or discipline must be recognized. Furthermore, utilitarianism does not explain why a good is or should be desired. Another difficulty inherent in utilitarianism as a philosophy is its inability to deal with competitive happiness, the valuation of relative happinesses between or among individuals. This difficulty accounts for a large portion of welfare economics literature. Even the rigorous, almost unattainable Pareto optimum does not address the essential question of the original d stribution of resources (means):
Phosphorus‐containing imide resins. III

Three imide monomers were prepared by reacting maleic anhydride; 2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride, bis(m-aminophenyl) methyl phosphine oxide, and tris(m-aminophenyl) methyl phosphine oxide, and tris (m-aminophenyl) phosphine oxide. The characterization was done by elemental analysis and infrared spectroscopy (IR). These monomers were soluble in acetone. Their thermal polymerization was investigated by differential scanning calorimetry (DSC). The temperature of the exothermic peak position was influenced by the presence of free amino group in the monomer and was about 50°C higher in monomers that did not contain amino group. Anaerobic char yield of imide monomers cured at 270 ± 2°C for 30 min ranged from 58 to 64%. Graphite cloth laminate fabricated from one of these resins had a limiting oxygen index of 100.
Response of the rat aortic wall to hypertension: importance of comparing absolute amounts of wall components.

Abstract The amounts of elastin and collagen in identical segments of thoracic aortas of normotensive and hypertensive male rats were compared. The absolute amounts of elastin and collagen were significantly increased in vessels from hypertensive animals; however, the relative amounts (percentages) of elastin and total fibrous protein were not significantly different. When indisputable evidence for a net change in the amount of a tissue component is desired, it is imperative to compare absolute amounts of that component in denticial, anatomically-defined tissue samples.
Crosslinked Epoxy Polymers With Large And Stable Nonlinear Optical Susceptibilities

A novel type of second-order nonlinear optical (NLO) polymer has been prepared by the reaction between tetrafunctional nitro-substituted aromatic diamines and difunctional epoxy monomers. In these materials the NLO-active moieties are incorporated covalently into the network of a crosslinked polymer. For comparison the corresponding linear (not crosslinked) polymers have also been prepared. The noncentrosymmetry was induced by poling under strong electric fields either with electrodes in liquid crystal display type cells or by corona discharge poling of spin-coated films. The resulting nonlinear optical susceptibilities were evaluated from second harmonic generation experiments. The linear polymer prepared from 4-nitroaniline and bisphenol-A diglycidylether initially exhibits a nonlinear coefficient d33 of 31 pm/V measured at 532 nm. However, 28 days after the poling, d33 decayed to 22 pm/V. This relaxation is comparable to that of a NLO polymer containing a similar chromophore as a side group that we investigated earlier. A significant improvment of the stability of the nonlinear optical coefficients was achieved with the crosslinking epoxy NLO polymers. These materials can be easily melt- or solution-processed in the form of soluble, low molecular weight prepolymcrs. Subsequently, the prepolyiners are simultaneously poled and cured to give crosslinked polymers with high glass transition temperatures. For a crosslinked polymer synthe-sized from 4-nitro 1,2-phenylenediamine and bisphenol-A diglycidylether, a d33 value of 14 pm/V was found. This high nonlinear optical coefficient remained unchanged under ambient conditions for at least 500h. Even at 85°C no signs of relaxation were detected.
Therapeutic approach to pancreatic extract-induced hyperuricosuria in cystic fibrosis

The relationship between the dosage of pancreatic extract and the excretion of uric acid was investigated in 29 patients with cystic fibrosis and exocrine pancreatic insufficiency. Urinary excretion of uric acid was normal in patients receiving small doses of pancreatic extracts and abnormally high in those receiving large amounts. In the latter group, normouricosuria was achieved by reducing the dose of pancreatic extract. Normal stool patterns and adequate weight gains were preserved by a diet modification that was well accepted by the patients. to eliminate the potential renal consequences of hyperuricosuria, it seems appropriate to control the need for increasing amounts of pancreatic enzymes by limiting the dietary intake of fat and maintaining a positive caloric and nitrogen balance with high intake of protein and carbohydrates and supplementation with medium-chain triglycerides.
Molecular heterogeneity in the amino-terminal region of alkaline phosphatase☆

Abstract It was reported earlier that a phosphatase nonsense mutant produces more than one molecular species of phosphatase fragment, a surprising result since the Escherichia coli chromosome contains only one phosphatase structural gene. The present experiments show that different species of fragments from the same mutant have different amino-terminal sequences. In the ochre mutant S 10, two of the fragments differ slightly in molecular size; two residues present in the larger fragment, namely the amino-terminal histidine and an internal (probably adjacent) valine, are missing from the amino-terminal region of the smaller fragment. As an explanation for this observation, we postulate that the nonsense mutant initially produces one uniform species of fragment, and that different species are generated subsequently by the action of an aminopeptidase which releases a variable number of residues from the fragment molecules. This mechanism could also account for the occurrence, in phosphatase-positive strains, of different species of isozymes of the standard phosphatase molecule.
High-Resolution n.m.r. in Solids with Strong Homonuclear Dipolar Broadening: Combined Multiple-Pulse Decoupling and Magic Angle Spinning

The theory of homonuclear decoupling combined with magic angle spinning is developed in the average Hamiltonian formalism. A description of pulse sequences used to tune for pulse width, pulse phase difference, and to minimize phase transient impurities is given. Resolution of n.m.r. spectra of $^{1}$H in crystalline, partly crystalline and amorphous solids under various pulse sequences with and without magic angle spinning are illustrated. Sources of residual broadening are discussed.
Recent oceanogeaphic work carried on jointly by the museum of comparative zoology, and by the U.S. Bureau of Fisheries

Since 1912, the chief field of this joint exploration, still continuing, has been the Gulf of Maine, with the coastal waters to the east and southward to Chesapeake Bay. A general survey has been made of the plankton, as well as of the physical oceanography; while the Bureau of Fisheries is prosecuting a study of the Biology of the important food fishes. In the winter of 1914, the oceanic triangle Chesapeake Bay-Bermtfda-Bahamas, and the Straits of Florida were surveyed oceanographically by the Bureau of Fisheries and the U.S. Coast and Geodetic Survey, jointly. In the winter of 1919–1920, the “Albatross” took observations along the South Atlantic coast and about Cuba.
Perturbed Series in Line Spectra

There occur many line series in atomic spectra which do not even approximately fit a Ritz formula. They display either a sudden rise in the value of ${n}^{*}\ensuremath{-}n$ towards high term values or a gradual fall of almost a unit. The latter type contains an extra term due to some other structure and becomes similar to the first type after the removal of that term. It is shown that all such series obey approximately a series formula of type ${\ensuremath{\nu}}_{n}=\frac{R}{{n}^{*2}}$, ${n}^{*}=\ensuremath{\mu}+\ensuremath{\alpha}{\ensuremath{\nu}}_{n}+(\frac{\ensuremath{\beta}}{{\ensuremath{\nu}}_{n}}\ensuremath{-}{\ensuremath{\nu}}_{0})$ in which ${\ensuremath{\nu}}_{0}$ is the wave number of some level of the same type from a different electron structure. The series in the spectra Ca I, Ba I, Hg I, Cu I, Al II are discussed in detail. The rules governing the occurrence of a perturbation are more restricted than the simple ones that can be deduced from the results in other perturbation problems. The constant $\ensuremath{\beta}$ is always negative and the trems therefore appear to repel each other. The Ba I levels $5d6p^{31}P^{0}{D}^{0}{F}^{0}$ and the series $6snf^{1}F^{0}$ are given for the first time.
Demonstration of a folded configuration of a fiber-Sagnac-based sensor array

The construction and performance of a two-sensor fiber-Sagnac- based sensor array is reported. The array is constructed in a folded configuration which passively desensitizes the delay coil to phase modulations. Experimentally, the delay coil desensitization is measured to agree with predictions. The sensor phase sensitivity is measured to be as low as 3 (mu) rad/(root)Hz and 0.8 (mu) rad/(root)Hz in a single- detection and a balanced-detection configuration, respectively.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Sex Differences in Selecting Between Food and Cocaine Reinforcement are Mediated by Estrogen

Cocaine-dependent women, relative to their male counterparts, report shorter cocaine-free periods and report transiting faster from first use to entering treatment for addiction. Similarly, preclinical studies indicate that female rats, particularly those in the estrus phase of their reproductive cycle, show increased operant responding for cocaine under a wide variety of schedules. Making maladaptive choices is a component of drug dependence, and concurrent reinforcement schedules that examine cocaine choice offers an animal model of the conditions of human drug use; therefore, the examination of sex differences in decision-making may be critical to understanding why women display a more severe profile of cocaine addiction than men. Accordingly, we assessed sex and estrous cycle differences in choice between food (45 mg grain pellets) and intravenous cocaine (0.4 or 1.0 mg/kg per infusion) reinforcement in male, female (freely cycling), and ovariectomized (OVX) females treated with either estrogen benzoate (EB; 5 μg per day) or vehicle. At both cocaine doses, intact female rats choose cocaine over food significantly more than male rats. However, the estrous cycle did not impact the level of cocaine choice in intact females. Nevertheless, OVX females treated with vehicle exhibited a substantially lower cocaine choice compared with those receiving daily EB or to intact females. These results demonstrate that intact females have a greater preference for cocaine over food compared with males. Furthermore, this higher preference is estrogen-dependent, but does not vary across the female reproductive cycle, suggesting that ovarian hormones regulate cocaine choice. The present findings indicate that there is a biological predisposition for females to forgo food reinforcement to obtain cocaine reinforcement, which may substantially contribute to women experiencing a more severe profile of cocaine addiction than men.
DNA repair phenotype and cancer susceptibility—A mini review

DNA repair is a complicated biological process, consisting of several distinct pathways, that plays a fundamental role in the maintenance of genomic integrity. The very important field of DNA repair and cancer risk has developed rapidly in the past decades. In this review of selected published data from our laboratory, we describe mostly our work on the study of phenotypic markers of nucleotide excision repair (NER), as measured by the benzo(a)pyrene diol epoxide (BPDE)/ultraviolet (UV)-induced mutagen sensitivity assays, BPDE-induced adduct assay, host cell reactivation (HCR)-DNA repair capacity (DRC) assay, reverse transcription-polymerase chain reaction (RT-PCR) assay and reverse-phase protein lysate microarray (RPP) assay, by using peripheral blood lymphocytes in a series of molecular epidemiological studies. Results of our studies suggest that individuals with reduced DRC have an elevated cancer risk. This finding needs additional validation by other investigators, and we also discussed issues in conducting this kind of research in the future.
Culturally Distinctive and Academic Socialization: Direct and Interactive Relationships with African American Adolescents' Academic Adjustment.

Theories of ethnic minority development have largely suggested that African American parents engage in a combination of practices that include culturally distinctive socialization as well as behaviors that are characteristic of more universal forms of academic socialization. However, few studies have examined how these socialization dimensions interact to influence the academic adjustment of African American adolescents. The current study explored the independent and interactive roles of parental academic and culturally distinctive socialization on the academic adjustment of African American adolescents. The sample was comprised 144 African American adolescents (M = 12.4; SD = 1.14; 56% female). Findings provided partial support that cultural and academic socialization were independently associated with indicators of academic adjustment. However, the interaction between these dimensions also was associated with youths' adjustment in the academic domain.
Polaronic exciton in a parabolic quantum dot

A calculation of the variations of the energy and oscillator strength of the ground state of an exciton in an ionic quantum dot as a function of the dot size, using a parabolic confining potential and a variational approach, is presented. The strong exciton – phonon interaction is taken into account by using an effective potential between the electron and the hole as derived by Pollmann and Buttner. The values of the exciton binding energies calculated using this potential are compared with those obtained using statically screened Coulomb potential and are found to be considerably larger for all values of the quantum dot size. In small quantum dots, the electron – hole correlation is reduced as the single particle energies scale at a much faster rate than the interaction energy. This is manifested in the behavior of oscillator strength, which becomes less dependent on the form of the effective interaction as the quantum dot size is reduced.
EFFECTS OF CANOPY POSITION AND IRRADIANCE ON THE LEAF PHYSIOLOGY AND MORPHOLOGY OF PENTACLETHRA MACROLOBA (MIMOSACEAE)

Pentaclethra macroloba (Willd.) Kuntze (Mimosaceae) is a dominant late-successional tree species in the Atlantic lowland forests of Costa Rica. Leaves of P. macroloba from three heights in the forest canopy were compared with leaves of seedlings grown in controlled environment chambers under four different irradiance levels. Changes in leaf characteristics along the canopy gradient paralleled changes resulting from the light gradient under controlled conditions. The effect of light or canopy position on light-saturated photosynthesis was small, with maximum photosynthesis increasing from 5 to 6.5 ,umol m-2 s-I from understory to canopy. Both chamber grown and field leaves showed large adjustments in photosynthetic efficiency at low light via reductions in dark respiration rates and increases in apparent quantum yields. Light saturation of all leaves occurred at or below 500 ,umol m-2 s-1. Leaf thickness, specific leaf weight, and stomatal density increased to a greater extent than saturated photosynthesis with higher irradiance during growth or height in the canopy. As a result, there was a poor correspondence between leaf thickness and light-saturated photosynthesis on an area basis. It is concluded that Pentaclethra macroloba possesses the characteristics of a typical shade-tolerant species. ONLY A SMALL proportion (about 25%) of the canopy tree species in the Atlantic lowlands of Costa Rica are thought to be shade-tolerant and able to replace themselves under a closed canopy (Hartshorn, 1978). The majority of canopy trees require a treefall gap or some other opening in the overstory to reach the canopy (Hartshorn, 1978, 1980; Denslow, 1980). The environmental change from the understory to the canopy surface presents steep gradients of light, temperature, and humidity across which shade-tolerant trees must maintain positive carbon and water balances as they mature. Photosynthetic photon flux densities in the understory are approximately 1% of those in full sun (Fetcher, Strain, and Oberbauer, 1983); daily maximum vapor pressure deficits and maximum air temperatures may be 1.0 kPa and 2-3 C lower in the understory than in the canopy (Fetcher, Oberbauer, and Strain, 1985). The question arises: What acclimatory changes
Biological activities and modes of action of 9-α-d-arabinofuranosyladenine and 9-α-d-arabinofuranosyl-8-azaadenine

Abstract From earlier studies it is known that 9-α- d -arabinofuranosyladenine (α-araA) and 9-α- d -arabinofuranosyl-8-azaadenine (α-ara-8-azaA) bave in vitro antiviral activity, are cytotoxic, and are metabolized in mammalian cells to the triphosphates. This study was designed to compare the in vivo antiviral activities of these compounds and their loci of action with those of 9-β- d -arabinofura-nosyladenine (β-araA). the latter compound selectively inhibits DNA synthesis in intact cells, and its triphosphate is a known inhibitor of DNA polymerases and ribonucleotide reductase. Whereas β-araA was significantly effective in the treatment of systemic herpes simplex virus type 1 (HSV-1) infections in mice, α-araA and α-ara-8-azaA were therapeutically ineffective. α-AraATP at a concentration of ~1 mM did not inhibit (1) DNA polymerases present in crude extracts of cultured H.Ep.-2 cells; (2) DNA polymerases present in extracts of KB cells; (3) partially purified DNA polymerase-α from mouse embryo cells; or (4) DNA polymerases induced by HSV-1 and HSV-2. DNA polymerase-β from mouse embryo cells was inhibited to a small extent by 10−4 M α-araATP. In contrast, all of these enzymes were inhibited by β-araATP at a concentration of 10−5M (as shown in these or in earlier studies). the reductions of CDP and UDP by ribonucleotide reductase from L1210 cells were not inhibited by αaraATP (~10−3M), whereas β-araATP produced 70–80 per cent inhibition at this concentration. In cultured H.Ep.-2 cells, α-ara-8-azaA inhibited the incorporation of thymidine, uridine, and formate into macromolecules, but it was without effect on the incorporation of adenine and hypoxanthine, and produced marginal inhibition of the incorporation of leucine. α-Ara-8-azaA produced a dose-dependent inhibition of the accumulation of [14C] formyl-glycinamide ribonucleotide in H.Ep.-2 cells treated with azaserine and [14C] formate. These results indicate that the α-nucleosides inhibit nucleic acid synthesis by mechanisms different from those of β-araA.
Semi-microscopic analysis of multi-nucleon transfer and the 40Ca(α, p)43Sc reaction

Abstract A semi-microscopic model for analyzing multi-nucleon transfer reactions in the distorted-wave Born approximation is presented. This model, which is shown to be compatible with other semi-microscopic models, employs cluster form factors. The cluster spectroscopic factors are calculated using shell-model wave functions. Data from the 40Ca(α, p)43Sc reaction are presented and used to test the model. The relative cluster spectroscopic factors for a number of levels are found to be in agreement with those calculated using wave functions in an ( f 7 2 ) 3 basis.
Expression of ZAP-70 is associated with increased B-cell receptor signaling in chronic lymphocytic leukemia.

We examined isolated leukemia B cells of patients with chronic lymphocytic leukemia (CLL) for expression of zeta-associated protein 70 (ZAP-70). CLL B cells that have nonmutated immunoglobulin variable region genes (V genes) expressed levels of ZAP-70 protein that were comparable to those expressed by normal blood T cells. In contrast, CLL B cells that had mutated immunoglobulin variable V genes, or that had low-level expression of CD38, generally did not express detectable amounts of ZAP-70 protein. Leukemia cells from identical twins with CLL were found discordant for expression of ZAP-70, suggesting that B-cell expression of ZAP-70 is not genetically predetermined. Ligation of the B-cell receptor (BCR) complex on CLL cells that expressed ZAP-70 induced significantly greater tyrosine phosphorylation of cytosolic proteins, including p72Syk, than did similar stimulation of CLL cells that did not express ZAP-70. Also, exceptional cases of CLL cells that expressed mutated immunoglobulin V genes and ZAP-70 also experienced higher levels tyrosine phosphorylation of such cytosolic proteins following BCR ligation. Following BCR ligation, ZAP-70 underwent tyrosine phosphorylation and became associated with surface immunoglobulin and CD79b, arguing for the involvement of ZAP-70 in BCR signaling. These data indicate that expression of ZAP-70 is associated with enhanced signal transduction via the BCR complex, which may contribute to the more aggressive clinical course associated with CLL cells that express nonmutated immunoglobulin receptors.
Photothermal heating enabled by plasmonic nanoantennas for electrokinetic manipulation and sorting of submicron particles

The photo-induced collective heating enabled by a plasmonic nanoantenna array is for the first time harnessed for rapid concentration, manipulation and sorting of particles, with high throughput. This work could find application in biosensing, and surface enhanced spectroscopies.
SU-FF-T-221: Evaluation of An Electron Monte Carlo Dose Calculation Algorithm for Electron Beam Radiotherapy

Purpose: To systematically evaluate the electron Monte Carlo (eMC) dose calculation algorithm of the Eclipse treatment planning system and to identify factors that affect its calculation accuracy. Method and Materials: Percent depth dose (PDD) and profiles for each electron energy/applicator/depth combination were measured for four Varian Clinac 21EX Linacs. Cutout factors for various cutout sizes down to 3×3 cm2 were also measured. Statistical comparison between eMC calculation and measurement was performed for parameters such as shift in depth of PDD curves, field size, penumbra width, average dose difference within 80% of field size, beam symmetry, Bremsstrahlung dose, and cutout factor. Analysis of variance was used to identify factors that have significant influence on the observed discrepancies. Results: The agreement between measured and calculated 50% PDD depth was within ±2 mm for nearly all machine/energy/applicator combinations except the 6×6 6 MeV beams on three machines where maximum difference was 3.8 mm. The calculated field width was larger than that of measured in most of the cases but within 3%. The differences between calculated and measured penumbra were also within 3%. The calculated Bremsstrahlung doses were smaller than measurements, with a few exceptions. Analysis of variance identified machine as a significant variable for the observed discrepancies in PDD, field width, and penumbra, suggesting possible variations among linacs or the quality of measured data. Calculation grid size was found to have significant effect on calculation accuracy. Using grid size of 5 mm resulted in approximate 10% discrepancies. Reducing grid size yielded significant improvement on the calculated cutout factor: from 5% discrepancy to less than 3% when grid size of 1 mm was used. Conclusion: The overall agreement between the eMC calculation and measurements was acceptable. Calculation grid size of 2.5 mm or smaller is recommended for all field sizes for eMC algorithm.
Transient polycondensation calculations—an analytical solution

Abstract An analysis is presented of transient irreversible polycondensation in a continuous well-stirred reactor. An exact analytical solution is obtained of the infinite set of rate equations previously solved by others using numerical methods, and close agreement is found. The analytical solution suggests a method to simplify future numerical analysis of more realistic and complex polycondensation systems.
Patient Compliance to Wear Orthodontic Retainers During Postretention may Vary by Age, Gender, and Time Since Braces Were Removed

Article Title and Bibliographic Information Patient compliance with orthodontic retainers in the postretention phase. Pratt MC, Kluemper GT, Lindstrom AF. Am J Orthod Dentofacial Orthop 2011;140:196-201. Reviewer Katherine W.L. Vig, BDS, MS, DOrth, FDS, RCS(Eng) Purpose/Question To evaluate and quantify compliance of orthodontic retainer wear and predictors for noncompliance during the postretention phase Source of Funding Information not available Type of Study/Design Survey Level of Evidence Level 3: Other evidence Strength of Recommendation Grade Not applicable
Endoscopic argon plasma coagulation of Marlex mesh erosion after vertical-banded gastroplasty

Background Marlex mesh erosions may occur as late complications after vertical-banded gastroplasty. Experience with the endoscopic treatment is limited. Objective To describe the use of argon plasma coagulation in the endoscopic treatment of eroded Marlex mesh. Design Case report. Settings Endoscopy Unit, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA. Patients We describe the endoscopic treatment of eroded Marlex mesh in 2 patients who presented with symptoms of gastric-outlet obstruction. Interventions In both cases, argon plasma coagulation was used to break down the eroded Marlex mesh. Fragments were subsequently removed with forceps and electrocautery snares. We did not encounter any complications with this method. Results The endoscopic treatment resulted in lasting symptomatic improvement in both patients. Limitations Our experience is limited to 2 cases. Conclusions Argon plasma coagulation appears to be a promising option for the endoscopic treatment of eroded Marlex mesh. It allows the fragmentation of large mesh portions and enables subsequent removal with a snare and a forceps. This method can result in symptomatic improvement and may obviate the need for surgery. Further data are necessary to evaluate the safety and the efficacy of this approach.
Cohort size and migration in a West Indian population.

The author examines the relationship between cohort size and migration patterns among the population of the French West Indies island of St. Barthelemy. Data show that "for people born from 1878 to 1967 neither cohort size nor fluctuations in external demands for labor had a lasting effect on the probability of eventual migration. Emigration rates only slowed after the development of the local tourist industry brought prosperity to the island." (EXCERPT)
Split-Ring Resonator Enhanced Terahertz Antenna

An electric split-ring resonator is used to enhance the performance of a photoconductive dipolar antenna based terahertz transmitter. Enhancement is observed near and limited to the resonant frequency of the electric split-ring resonator.
Application of the estimation of normal distributions from truncated samples to the analysis of flow microfluorometry histograms

Abstract The procedure for estimation of a singly truncated sample drawn from a normal distribution is applied to the analysis of DNA distribution histograms obtained from flow microfluorometry (FMF). The method improves the accuracy of the estimation of the parameters for the pre-DNA synthesis stage. Simulated FMF histograms as well as actual experimental histograms are used to test the accuracy of the estimation method.
Examination of herpes virus dna sequences for patterns that resemble transposable elements

Herpes viruses are associated with many types of oral tumors and can be tumorigenic in vitro. The mechanisms by which they transform cells remain unknown, but it has been suggested that they contain insertion sequences. Two algorithms were developed to search DNA sequences for the presence of patterns that characterize such elements using either selection or scoring techniques. When randomly shuffled herpes virus sequences were examined each algorithm detected many such patterns but the scoring algorithm found fewer than the selection algorithm. In the herpes virus sequences that are known to contain such patterns the computer techniques found many more than previously reported, indicating that visual inspection alone is not adequate. The frequency of these patterns suggest that although the transforming regions of herpes virus DNA could contain transposable elements experimental confirmation is necessary.
Cauda equina syndrome after incidental total spinal anesthesia with 2% lidocaine.

Abstract A 17-year-old male presented for a right popliteal distal vein bypass graft procedure with continuous epidural anesthesia and light general endotracheal anesthesia. After the uneventful placement of the epidural needle and catheter at the L 2 -L 3 interspace, fentanyl 150 ug and a total of 72 ml of preservative-free 2% lidocaine with epinephrine was continually injected through the epidural catheter for the duration of the more than 5 hour procedure. At the end of the procedure, it was noted that the patient had developed total spinal anesthesia, and his pupils were fixed and dilated. Further examination confirmed that the catheter tip was placed in the subarachnoid space. The patient was unable to turn or sit up by himself for over 1 month. Over a 12-month period, he improved to walking with a quad cane, but he required self-catheterization. Although numerous factors were considered, neurotoxicity of 2% lidocaine solution has been discussed as the potential cause. We were unable to find any other factors that could have caused the cauda equina syndrome.
Optimizing the Assembly of Stacked Rings

Many macromolecular machines inside the cell exhibit a “stacked ring” architecture, with multiple uniform-length rings of protein subunits bound to one another. The majority of these machines must adopt their fully assembled quaternary structure in order to function, making the assembly process vital for cellular function and survival. The assembly of protein complexes containing stable substructures has been shown to suffer from a type of kinetic trapping that we term “assembly deadlock,” which occurs when smaller intermediates are exhausted from the system before all of the fully functional structures have formed. Deadlock can result in plateaus in the assembly dynamics, leading to delays in reaching maximum complex assembly and a reduced final complex concentration. While these plateaus have been extensively studied for simple rings, the effect of assembly deadlock on more general structures like stacked rings remains to be fully investigated. In this work, we focused on the case of a stacked homotrimer; this structure contains both three- and four-member rings as substructures, but is simple enough to allow for extensive investigation. Our mathematical models revealed that this structure could suffer from extreme deadlock that significantly reduces the efficiency of assembly. Using a computationally efficient simulation approach, we exhaustively analyzed the parameter space of self-assembly for this case, and found that the number and duration of plateaus in the assembly dynamics depended strongly on the pattern of affinities in this structure. Since these complexes are generally only functional when fully assembled, we hypothesized that existing stacked ring architectures would evolve to utilize the most efficient assembly pathways predicted by our models. Analysis of interfaces in solved crystal structures of stacked homotrimers confirmed this prediction. Our findings have important implications for understanding how assembly dynamics have influenced the structural evolution of large macromolecular machines.
Systemic lupus erythematosus (SLE) cerebritis versus Listeria monocytogenes meningoencephalitis in a patient with systemic lupus erythematosus on chronic corticosteroid therapy: the diagnostic importance of cerebrospinal fluid (CSF) of lactic acid levels.

Abstract Background Listeria monocytogenes is a motile, aerobic, Gram-positive intracellular bacillus that causes enteritis, meningitis, meningoencephalitis, or subacute bacterial endocarditis. Patients with impaired T-lymphocyte function/cell-mediated immunity are predisposed to intracellular pathogens, e.g., L. monocytogenes. In adults, infection by L. monocytogenes of the central nervous system (CNS) clinically manifests as either acute bacterial meningitis or meningoencephalitis. In patients with systemic lupus erythematosus (SLE) presenting with headache and fever, SLE cerebritis must be differentiated from acute bacterial meningitis by lumbar puncture and cerebrospinal fluid (CSF) analysis. Neuropathogenic viruses are the most common causes of meningoencephalitis. The most rapid and accurate way to differentiate bacterial meningoencephalitis from nonbacterial meningoencephalitis is CSF lactic acid levels. Methods We present a patient receiving chronic corticosteroid therapy and manifesting SLE and severe L. monocytogenes meningoencephalitis. An early diagnosis of L. meningoencephalitis was achieved by demonstrating a very highly elevated level of lactic acid in his CSF, days before CSF and blood cultures tested positive for L. monocytogenes. Results and Conclusion In this patient, the highly elevated levels of lactic acid in his CSF ruled out both viral meningoencephalitis and SLE cerebritis. The case was complicated by communicating hydrocephalus, and the patient later underwent placement of a shunt. He completed 6 weeks of meningeal dosed ampicillin.
Rapid photothermal intracellular drug delivery using multiwalled carbon nanotubes

Carbon nanotubes are unique materials that absorb infrared (IR) radiation, especially between 700 and 1100 nm, where body tissues are most transparent. Absorbed IR promotes molecular oscillation leading to efficient heating of the surrounding environment. A method to enhance drug localization for peritoneal malignancies is perfusion of warm (40-42 degrees C) chemotherapeutic agents in the abdomen. However, all tissues in the peritoneal cavity are subjected to enhanced drug delivery due to increased cell membrane permeability at hyperthermic temperatures. Here we show that rapid heating (within ten seconds) of colorectal cancer cells to 42 degrees C, using infrared stimulation of nanotubes as a heat source, in the presence of the drugs oxaliplatin or mitomycin C, is as effective as two hours of radiative heating at 42 degrees C for the treatment of peritoneal dissemination of colorectal cancer. We demonstrate increased cell membrane permeability due to hyperthermia from multiwalled carbon nanotubes in close proximity to cell membranes and that the amount of drug internalized by colorectal cancer cells heated quickly using carbon nanotubes equals levels achieved during routine application of hyperthermia at 42 degrees C. This approach has the potential to be used as a rapid bench to bedside clinical therapeutic agent with significant impact for localizing chemotherapy agents during the surgical management of peritoneal dissemination of colorectal cancer.
Reentry device aided endovascular aneurysm repair in patients with abdominal aortic aneurysm and unilateral iliac artery occlusion.

Background We report 2 cases of patients undergoing endovascular aneurysm repair (EVAR) using reentry devices to recanalize unilateral iliac artery occlusions and complete a bifurcated endovascular repair. Methods Patient 1 is a 70-year-old male with an enlarging 6.5-cm abdominal aortic aneurysm (AAA) and disabling left leg claudication with L external iliac occlusion with patent common and internal iliac arteries. Patient 2 is a 67-year-old male with an asymptomatic 4.0-cm AAA and L iliac chronic total occlusion (CTO) and disabling claudication. Both patients were poor operative candidates for open repair. Results Both patients underwent elective percutaneous EVAR along with left iliac artery revascularization. Initial angiography in both cases showed a blind ending of the left common iliac artery. Retrograde subintimal dissection through the occluded iliac segment was attempted but in both cases the wire was unable to traverse back into the true aortic lumen. Using either the Outback LTD or Pioneer reentry catheter, direct visualization of the true aortic lumen was obtained to re-enter the true lumen. The subintimal iliac tract was then predilated to facilitate routine EVAR in both cases. Both patients were discharged the following day and 1-year and 6-month follow-up imaging revealed aneurysm exclusion, no endoleak, and patent bilateral common iliac arteries with resolution of claudication symptoms and normal ankle-brachial indexes. The previously patent internal iliac artery was preserved. Conclusions While not always technically possible, reentry device aided EVAR is safe, feasible, and durable in the mid-term and avoids the morbidity and mortality related to aortouniiliac/femoral–femoral bypass and open repair. This technique should be considered in patients with iliac artery CTO and concurrent AAA to allow total endovascular repair.
Self-Assembly of Spherical Particles on an Evaporating Sessile Droplet

Particles adsorbed on the surface of a droplet form three-dimensional packings when the droplet evaporates. We study the final packings when the liquid droplet is attached to a solid substrate. In contrast to a droplet evaporating away from a substrate, here the final packings are highly dependent on both the number of particles and the contact angle between the droplet and the surface. Simple geometrical constraints quantitatively determine the parameter regions that particular packings can form.
Wind Turbine Clutter mitigation for weather radar by Adaptive Spectrum Processing

Wind Turbine Clutter (WTC) is the radar clutter caused by strong backscatter from large wind turbines within the radar vicinity. Due to the rotation of the rotor blades, the Doppler spectrum of WTC varies from scan to scan. This time-varying radar signature results in the failure of classic ground clutter filter techniques. The Adaptive Spectrum Processing (ASP) algorithm proposed in this paper explores the spatial and spectral characteristics of weather returns in weather radar, and adaptively generates band pass filters based on the moment estimates of uncontaminated weather in detected wind farm region. The actual NEXRAD weather radar data have been used to verify this algorithm. The experiment shows significant improvement on moment estimation in terms of both bias and variance.
The kinetics of growth of an aerosol in a flow reactor. II. Theoretical

Abstract The data of Part I concerning the rate of growth of dibutyl phthalate aerosol droplets by condensation from a supersaturated atmosphere are interpreted successfully over the early stages of the growth process in terms of a collision hypothesis based upon the kinetic theory of gases. Over the later stages of growth, however, it is necessary to postulate a diffusion controlled rate law. Under either hypothesis, the accommodation coefficient of vapor molecules striking the liquid surface is unity.