cssi/SciSciGPT-SciSciNet huggingface dataset:
Improved cycling stability of silicon thin film electrodes through patterning for high energy density lithium batteries

Abstract The mechanical degradation of electrodes caused by lithiation and delithiation is one of the main factors responsible for the short cycle life of lithium-based batteries employing high capacity electrodes. In this report, we introduced a simple patterning approach to improve the cycling stability of silicon electrode, which is considered as the next generation negative electrode due to its high Coulombic capacity and low cost, but is limited by the mechanical degradation associated with large volume variations during cycling. The pattern design is based on the observation of a critical size for the crack gap in continuous films. An improvement in cycle life was noted when the pattern size was below the critical (7–10 μm) size, in which case the Si electrode patches adhered well to the Cu substrate after many cycles. By taking the plastic deformation in both Si thin film and substrate into consideration, the calculated crack spacing is consistent with experimental observations. Theoretical considerations gave a feasible explanation for the failure of Si pattern above the critical size. These results suggest a new approach to extend the cycle life of Si-based electrode materials using size to control and relax the stress due to lithiation and delithiation.
Correcting soil acidification in continuous corn (zea mays L.): N rate, tillage and time

Abstract Use of ammoniacal N in continuous corn production results in greater acidification of the surface soil layer under conservation tillage. Moldboard plowing results in dilution of acid inputs to greater depth. The objective of this work was to observe soil reaction after a lime application made to a continuous corn experiment initiated in 1970. Four fertilizer N rates (0. 84. 168. and 336 kg N ha‐1) and two primary tillage systems (no‐tillage and moldboard plowing) were used. Lime application was made to half of each plot in 1983. Control of developed acidity was achieved the first year on the plowed soil. This was not the case on the most acid no‐till soil, where both corn dry matter production and leaf Mn concentration also indicated persistence of acidity. Surface lime application resulted in soil pH changes limited to the upper 10 cm of no‐till soil. Shallow incorporation of lime may be needed to more quickly control strongly developed acidity in no‐till soils.
EMBLEM2: An empirically based large scale evacuation time estimate model

This article describes a simple, rapid method for calculating evacuation time estimates (ETEs) that is compatible with research findings about evacuees' behavior in hurricanes. This revision of an earlier version of the empirically based large scale evacuation time estimate method (EMBLEM) uses empirical data derived from behavioral surveys and allows local emergency managers to calculate ETEs by specifying four evacuation route system parameters, 16 behavioral parameters, and five evacuation scope/timing parameters. EMBLEM2 is implemented within a menu-driven evacuation management decision support system (EMDSS) that local emergency managers can use to calculate ETEs and conduct sensitivity analyses to examine the effects of plausible variation in the parameters. In addition, they can run EMDSS in real time (less than 10 min of run time) to recalculate ETEs while monitoring an approaching hurricane. The article provides an example using EMDSS to calculate ETEs for San Patricio County Texas and discusses directions for further improvements of the model.
Fortuitous detection of a sporadic carrier of Duchenne's muscular dystrophy.

A case is presented of a 19-year-old white female, detected while we were investigating the range of serum creatine kinase levels in “normal” controls. She presented elevated serum creatine kinase, myopathic electromyogram, and electron microscopic evidence of dystrophic changes in muscle tissue, but no clinically detectable muscular weakness. The significance of these findings is discussed. We felt that she was probably a sporadic carrier of the gene for Duchenne's muscular dystrophy and, because there was no family history of neuromuscular disease, that this was the result of a spontaneous mutation.
Brain circuit dysfunction in a distinct subset of chronic psychotic patients

Abstract Objective To identify the mechanism of unexplained hyponatremia and primary polydipsia in schizophrenia and its relationship to the underlying psychiatric illness. Methods Briefly review previous studies that led to the conclusion the hyponatremia reflects altered hippocampal inhibition of peripheral neuroendocrine secretion. In greater detail, present the evidence supporting the hypothesis that circuit dysfunction associated with the hyponatremia and the polydipsia contributes to the underlying mental disorder. Results Polydipsic patients with and without hyponatremia exhibit enhanced neuroendocrine responses to psychological stress in proportion to structural deformations on their anterior hippocampus, amygdala and anterior hypothalamus. Nonpolydipsic patients exhibit blunted responses and deformations on other hippocampal and amygdala surfaces. The deformations in polydipsic patients are also proportional to diminished peripheral oxytocin levels and impaired facial affect recognition that is reversed by intranasal oxytocin. The anterior hippocampus is at the hub of a circuit that modulates neuroendocrine and other responses to psychological stress and is implicated in schizophrenia. Preliminary data indicate that other measures of stress reactivity are also enhanced in polydipsics and that the functional connectivity of the hippocampus with the other structures in this circuitry differs in schizophrenia patients with and without polydipsia. Conclusion Polydipsia may identify a subset of schizophrenia patients whose enhanced stress reactivity contributes to their mental illness. Stress reactivity may be a symptom dimension of chronic psychosis that arises from circuit dysfunction that can be modeled in animals. Hence polydipsia could be a biomarker that helps to clarify the pathophysiology and heterogeneity of psychosis as well as identify novel therapies. Clinical investigators should consider obtaining indices of water balance, as these may help them unravel and more concisely interpret their findings. Basic researchers should assess if the polydipsic subset is a patient group particularly suitable to test hypotheses arising from their translational studies.
Action potentials pass severed earthworm MGA segments reconnected by laser and electric field pulses

Abstract Active and passive electrical signals transmit across the earthworm (Lumbricus terrestris) medial giant axon (MGA) segment after reconnection induced by laser and electric field pulses. Laser pulses of 308 nm, 15 ns pulse duration, and pulse energy 5–50 μJ in the objective plane induced axon reconnection in 12 of 133 (9%) preparations. Electric field pulses of 200–800 V,100 μs duration, induced axon reconnection in 15 of 188 (8%) preparations. Electrical continuity is possible after the reconnection of severed axons induced by laser and electric field pulses.
DNA electrophoresis in a sparse ordered post array

We present a study of the electrophoresis of long DNA in a strong electric field through a hexagonal array of cylindrical microscale posts spaced such that the pore size is commensurate with equilibrium coil size of the DNA. Experimental mobility, dispersivity, and videomicroscopy data indicate that the DNA frequently collide with the posts, contradicting previous Brownian dynamics studies using a uniform electric field. We demonstrate via simulations that the frequent collisions, which are essential to separations in these devices, are due to the nonuniform electric field, highlighting the importance of accounting for electric-field gradients when modeling DNA transport in microfluidic devices.
Ethics in reproductive and perinatal medicine: A new framework

Ethics in reproductive and perinatal medicine: A new framework. Carson Strong (Yale University Press, New Haven, Connecticut, 1997), 256 pages, $30.
Fabrication of functionally graded porous polymer via supercritical CO2 foaming

Abstract A fabrication process to produce functionally graded porous polymer via supercritical carbon dioxide (ScCO2) foaming is reported in this paper. It utilizes a partial gas saturation technique to obtain non-equilibrium gas concentration profiles in thermoplastic polymer. Once foamed the polymer material obtains a graded foam–solid-foam structure with varying pore size distributions. This functionally graded material fabrication method was studied with polymethyl methacrylate (PMMA) under a ScCO2 saturation condition. A diffusion model was developed to estimate the gas diffusion coefficient and to predict the gas concentration profiles inside the polymer samples. Scanning electron microscopy images were used to analyze the effects of partial saturation on the graded porous structure. Mechanical properties of the foamed samples were characterized using a three-point bending test. It was found that the gas concentration profiles resulted from partial saturation corresponded well to the graded structure after foaming. The proportion of the foam and solid regions inside the polymer sample can be manipulated by controlling the partial saturation profile. The test results also suggested that the graded foam structure could be optimized to achieve desirable mechanical properties.
THE SIGNIFICANCE OF BACTEREMIA WITH EXCHANGE TRANSFUSIONS.

From a study of blood cultures obtained during 100 exchange transfusions, it is concludedthat an induced bacteremia occurs in approximately 10% of cases. This bacteremia is transient and only rarely leads to septic complications. Blood cultures taken during exchange transfusions are unreliable as indicators of septicemia. Prophylactic antibiotic therapy is not warranted for babies undergoing routine exchange transfusions.
Mitotic Index of Hyperplastic Interstitial Cells of the Guinea Pig.

ConclusionsThe scarcity of cell divisions among the interstitial cells of the testes of PU-treated animals makes unlikely the conclusion that the increase in the number of these cells is due, except to a slight degree, to their mitosis. Observations were presented which support the opinions of Esaki,1and others that the interstitial cells have an extrinsic origin. Other data, to be presented elsewhere, indicate that certain intertubular connective tissue elements are differentiated into active secreting Leydig cells by the action of the gonadotropic hormones of pregnancy urine.
The recombination hot spot chi activates RecBCD recombination by converting Escherichia coli to a recD mutant phenocopy

Abstract The products of the recB and recC genes are necessary for conjugal recombination and for repair of chromosomal double-chain breaks in Escherichia coli. The recD gene product combines with the RecB and RecC proteins to comprise RecBCD enzyme but is required for neither recombination nor repair. On the contrary, RecBCD enzyme is an exonuclease that inhibits recombination by destroying linear DNA. The RecD ejection model proposes that RecBCD enzyme enters a DNA duplex at a double-chain end and travels destructively until it encounters the recombination hot spot sequence chi. Chi then alters the RecBCD enzyme by weakening the affinity of the RecD subunit for the RecBC heterodimer. With the loss of the RecD subunit, the resulting protein, RecBC(D-), becomes deficient for exonuclease activity and proficient as a recombinagenic helicase. To test the model, genetic crosses between lambda phage were conducted in cells containing chi on a nonhomologous plasmid. Upon delivering a double-chain break to the plasmid, lambda recombined as if the cells had become recD mutants. The ability of chi to alter lambda recombination in trans was reversed by overproducing the RecD subunit. These results indicate that chi can influence a recombination act without directly participating in it.
Social Support in Academic Programs and Family Environments: Sex Differences and Role Conflicts for Graduate Students.

We hoped to identify the sources and types of social support that are most beneficial for helping graduate students cope with stress. A second purpose of our study was to identify sex differences in stress and the most beneficial types of support. Students living in graduate student housing were surveyed to assess (a) social support in their academic programs and in their family environments, (b) recent stressful life events, and (c) depression and anxiety as psychological symptoms of stress. Women reported significantly more stress, more symptoms of stress, and significantly less support from their academic departments and family environments than did men. Family support had only buffering effects, but no direct effects on stress symptoms for women. Graduate program and family support had direct effects, but no buffering effects on stress symptoms for men. These results may indicate greater role strain for women, perhaps resulting from less support for their multiple roles and greater concerns about balancing academic and family demands.
Caspofungin for the treatment of immunocompromised and severely ill children and neonates with invasive fungal infections

Caspofungin is the first member of the echinocandin class of antifungals to receive an indication for the use in infants, children, and adolescents from the United States Food and Drug Administration. Daily doses of 50 mg/m2 result in pharmacokinetic parameters that are similar to those observed in adults. Although fewer data are available, the response rates in pediatric patients who received caspofungin either as treatment or empiric therapy in clinical trials are similar to those reported in adults. In addition, caspofungin appears to be generally safe and well tolerated in this population. This represents a significant step forward in the treatment of invasive fungal infections within this population, as caspofungin is associated with few clinically significant drug-interactions and toxicities compared to other antifungals, such as the azoles and amphotericin B.
Neurospora crassa and S1 nuclease cleavage in hsp 83 gene chromatin.

Abstract We have examined the distribution of Neurospora crassa and S1 nuclease cleavage products in the chromatin of the hsp 83 heat shock gene from the Drosophila melanogaster cytogenetic locus 63BC. Both of these nucleases generate double strand breaks in chromatin at specific sites close to the 5′ end of the hsp 83 gene. With N. crassa nuclease we observe one major 5′ fragment which is derived from nuclease cleavage in a DNA segment mapping ~ 120 base-pairs from the beginning of the transcription unit. With S1 nuclease we observe one major fragment which overlaps the transcription start site. In addition to the major hypersensitive sites at the beginning of the gene, the hsp 83 transcription unit is also sensitive to attack by these nucleases both before and after heat shock; however, the yield of cleavage products from within the gene is considerably greater after heat induction.
Phthalate ester hydrolysis: Linear free energy relationships

Abstract Alkaline hydrolysis rate constants were measured for dimethyl, diethyl, di- n -butyl, di- iso -butyl, and di-(2-ethylhexyl) phthalate esters in water. A linear free energy relationship (LFER) was established for estimating alkaline hydrolysis rate constants for other phthalate esters. Dimethyl phthalate hydrolyzes to phthalic acid with the mono ester as an intermediate. The rate ratio for the second-order-alkaline hydrolysis rate constants of the diester to the monoester is 12. Water solubilities for dimethyl, diethyl, di- n -butyl, di- n -octyl and di-(2-ethylhexyl) phthalate esters were measured and compared with literature values.
A large foreign body removed through the intact anus: report of a case.

A case in which an after-shave lotion bottle 21.5 cm in circumference, was retrieved through the intact anus is reported. The preoperative evaluation of objects to be removed is discussed, and techniques for their safe removal are presented.
Extensions of Bernstein's theorem on absolutely monotonic functions

The main result is that D n ( e a n x f ( x )⩾ 0 for n ⩾ 0 on [ a, b ] implies that f is analytic on [ a, b ] if ¯lim a n / n a n } ∼ is a non-decreasing sequence of non-negative numbers. The result is best possible in a well defined sense.
Factors Associated with Quality of Life: Perspectives of Stroke Survivors

Objective: The purpose of this mixed design study was to examine quality of life from the stroke survivors' perspectives. It addressed the question: What factors have influenced the stroke survivors' quality of life (QOL)? and tested the null hypothesis that stroke has no influence on stroke survivors' QOL.Methods: A mixed design was used with nine stroke survivors who lived at home, were able to communicate and had experienced a stroke at least one year prior to the interview. Four data collection methods were used, including a semi-structured qualitative interview tool, two standardized tools measuring the QOL (the Delighted-Terrible Scale and the Satisfaction with Life Scale (SWLS)), and field notes.Results: On the Delighted-Terrible Scale the null hypothesis was rejected since the Dmax was found to be more than the critical D (0.57 < 0.43), using the Kolmogorov-Smirnov One-Sample test. Similarly, on the SWLS the null hypothesis was rejected as the Dmax was found to be more than the critical D (0.49 < ...
Practice and incentive motivation in recognition of inverted faces.

Summary.-In each of three experimencs, participants received successive daily practice sessions on the task of recognizing inverted faces. In all practice sessions, an initial study series of 25 inverted faces was followed immediately by a test series of 17 pairs of inverted faces. Each test pair comprised a face from the study series and a new face. Completely new sets of faces were used in each session. Recognition of inverted faces did not improve across sessions in Exp. 1 but did improve in Exps. 2 and 3. Unlike Exp. 1, Exps. 2 and 3 employed an explicit incentive for improved performance. These results show chat sufficiently morivated participants can become quite proficient at recognizing inverted faces. Implications of the results for the role of expertise at recognition in producing the inversion effect are discussed. People are usually better at recognizing stimuli when these are presented in an upright orientation than if the stirnuh are inverted. The impaired recognition of inverted stimk relative to upright stimuli is called the inversion effect. Studies of human face recognition have shown that the recognition of faces, compared to other stimuli, is disproportionately impaired by stimulus inversion. Whereas upright faces are generally better recognized than other upright stimuli, inverted faces are harder to recognize than other stimuli. In other words, the face inversion effect is larger than the inversion effect for other stimuli (for reviews see Ehs, 1975; Valentine, 1988; Ellis & Young, 1989). The disproportionately large inversion effect for faces is generally seen
Improved local control of nasopharyngeal carcinoma after intracavitary brachytherapy boost.

In 1976 we began using intracavitary cesium boost technique as a portion of comprehensive treatment of primary T2 and T3 nasopharyngeal carcinoma. At first, we offered this procedure sporadically to patients with T1 lesions. For the past 10 years, intracavitary boost has been offered to all patients except those with T4 lesions. The radiation therapy program consists of external beam dose of 60-64 Gy, either once daily (q.d.) or twice daily (b.i.d.) schedule, followed by 10-15 Gy boost to mucosal surface by intracavitary implant, making a total of approximately 75 Gy. This article presents the experience at the Massachusetts General Hospital with 146 patients with T1-3 carcinoma of the nasopharynx irradiated from 1970 through 1988. Seventy-six patients were treated with intracavitary boost and 70 patients were treated up to 65-70 Gy by external beam alone. The overall 5-year actuarial local control rate for the T1 lesions was 93% after radiation therapy and intracavitary boost as compared with 54% without brachytherapy boost (p value = 0.057). For the T1-2 lesions, the corresponding local rates after external radiation therapy and brachytherapy boost and after external beam irradiation without boost were 90 and 59%, respectively, with p = 0.001. For the T3 lesions, the rates were 100 and 64%, respectively, with p = 0.090. The reason for improved local control is unclear and may be due to a somewhat higher mucosal dose to the nasopharynx. Hopefully, the improved beneficial local control effects may be reflected in improved patient survival. However, such data require a controlled randomized clinical trial for confirmation.
Comparison of hypersensitivity to adrenergic stimulation after abrupt withdrawal of propranolol and nadolol: Influence of half-life differences☆

To test whether a beta-blocker's pharmacokinetics has an effect on the development of the beta-blocker withdrawal syndrome, we compared response to exercise and isoproterenol after abrupt withdrawal of two beta-blockers, one with a short half-life (propranolol) and one with a long half-life (nadolol). Eight normal males participated in the randomized cross-over trial. They took propranolol, 40 mg every 6 hours for 6 days, and nadolol, 80 mg daily for 7 days. Exercise- and isoproterenol-induced changes in heart rate and pulse pressure were significantly less than control values during treatment with both drugs (p less than 0.05). Significant hypersensitivity of heart rate response was seen on days 2, 3, and 7 after propranolol withdrawal (p less than 0.05) and on day 6 after nadolol withdrawal (p less than 0.005). Hypersensitive responses to isoproterenol were seen after propranolol withdrawal; no evidence of hypersensitivity to isoproterenol was seen after nadolol withdrawal. The area under the heart rate response, time curve after nadolol withdrawal was significantly less than that after propranolol withdrawal (20.3 beats/min.day vs 44.9 beats/min.day, respectively, (p less than 0.05). There was a significant inverse correlation between the degree of hypersensitivity and nadolol pharmacokinetic half-life (r = -0.80, p less than 0.02). We conclude that abrupt withdrawal of a beta-blocker with a long half-life may protect against the development of the beta-blocker withdrawal syndrome.
Serotonin Toxicity Associated with Garcinia cambogia Over-the-counter Supplement

Garcinia cambogia, also known as the Malabar tamarind, is a plant that is commonly used in India and Southeast Asia for its sour taste and as a food-bulking agent [1]. The plant contains hydroxycitric acid (HCA) and has recently become a popular ingredient in over-the-counter supplements designed for weight loss and weight management [2]. Most of these supplements contain from 20 to 60 % HCA. There is limited evidence that HCA may increase serotonin concentrations and thereby increase the risk of serotonin toxicity. HCA analogs increase serotonin concentrations within the brains of rats [1, 3], and randomized human studies have found elevations in free serum serotonin concentrations after the administration of HCA derivatives [4]. We report a case of suspected serotonin toxicity in the presence of therapeutic dosing of serotonin reuptake inhibitors (SSRIs) when combined with a nutritional supplement containing G. cambogia and hydroxycitric acid.
Ground Observations of Power Line Radiation Coupled to the Ionosphere and Magnetosphere

Ground-based VLF observations show evidence that strong whistler-mode waves in the magneto-sphere are often stimulated by harmonic radiation from electrical power transmission lines. These stimulated emissions sometimes dominate the wave activity in the kHz range. A VLF transmitter at Siple, Antarctica has been used to simulate these power line effects with ∼ 0.5 W radiated power at a given frequency. Occurrence statistics of power line effects are also summarized.
Stability Analysis of a Hydraulic Free Piston Engine With HCCI Combustion

This paper analyzes the stability of the dynamic coupling among the homogeneous charge compression ignition (HCCI) combustion, gas exchange dynamics and the piston dynamics in a hydraulic free piston engine. The intrinsic feedback nature of the system makes the stability of the engine operation difficult to predict. Specifically, output from the gas exchange process of the previous cycle affects the combustion timing of the current cycle. The combustion force and hydraulic loading together determine how far the piston can travel (dead center positions) and provide input for the current cycle gas exchange process. A discrete cycle-to-cycle based model that captures this dynamic coupling is described in the paper. Linearization of the model gives us the insight of the engine stability under any given operation conditions. The stability analysis is validated with Matlab numerical simulation results of a high-order nonlinear model under a specified set of operation conditions. The proposed methodology can be transformed and applied to analyze stability of systems with similar dynamics couplings.Copyright © 2011 by ASME
Surgical management and ultrastructural study of choroidal neovascularization in punctate inner choroidopathy after bevacizumab

This study aims to describe surgical management results and the pathologic features of choroidal neovascularization (CNV) secondary to punctate inner choroidopathy (PIC) following anti-vascular endothelial growth factor treatment. This study is a case report on the surgical management and ultrastructural study of choroidal neovascularization. Clinicopathologic and ultrastructural report of CNV membranes excised from both eyes of one patient was presented. The right eye responded to bevacizumab, and recurrence 17 months later did not; the left eye never responded. Excision of the active CNVs was performed 3 months after the last injection. In the right eye, there was no recurrence 23 months after surgery. In the left eye, CNV recurred after 6 months, with no response to bevacizumab. Electron microscopy revealed subretinal neovascular tissue and, additionally, Bruch's membrane and inner choroid in the left. In the right eye, lumens of many neovascular channels were occluded by microfibrils and pericytes were infrequent. In the left eye, patent CNV units with pericytes were present. There were scattered macrophages but no lymphocytes in either membrane. An inner focal choroidal lymphocytic infiltrate was discovered. Submacular surgery did not cause complications following treatment with bevacizumab. Mostly nonfunctional capillaries in the right membrane failed to display pericytes. The left membrane, which was unresponsive to bevacizumab, displayed well-formed neovascular units consistently exhibiting pericytes. A focus of inner choroidal lymphocytic infiltration was found in the left eye despite the absence of overt clinical intraocular inflammation. This is the first pathological study employing human tissue that points to pericytes as a potential critical therapeutic target with the aggravating influence of inner choroidal chronic inflammation in PIC.
A topological field theory of gravitational instantons

Abstract A topological field theory modeling the moduli space of conformally (anti-) self-dual gravitational instantons is presented. The classical action is a functional of an SU((2) gauge field and a totally symmetric rank-four SU (2) spinor. Classical extrema of the action correspond to euclidean signature Einstein spaces with (anti-) self-dual Weyl tensor as well as a condition which governs the appearance of singularities in the space of instantons modulo the action of diffeomorphisms and local SU (2) transformations. A suitable fermionic supersymmetry is constructed as well as a supersymmetric extension of the classical bosonic action, both of which are a natural generalization (to include diffeomorphisms) of their counterparts in Witten's topological gauge theory. We discuss relevant properties of the moduli space and their implications for the quantized version of the theory.
Methane leaks from oil and gas fields detected from space

A few years ago, while poring over satellite images of the Earth at night, scientists spotted the bright glow of natural gas flares burning in the oil and gas fields that have fueled America's recent energy boom. Now they have spotted something else from space: large plumes of fugitive methane gas liberated from these formations by unconventional extraction methods like horizontal drilling and hydraulic fracturing.
Pubertal timing, hormones, and body composition among adolescent Turkana males.

The Turkana, like other East African pastoral groups, are known for their tall adult stature, achieved despite a blunted growth spurt during adolescence and continued growth into the early 20s. To investigate the hormonal mechanisms associated with the pattern of slow and continued adolescent growth, we collected data on hormonal status, height, weight, and trunk skinfolds and ethnographic self-reports of testicular maturation in a cross-sectional sample of 35 nomadic and 37 settled Turkana males aged 14–24. Hormonal determinations included testosterone (T), sex hormone-binding globulin (SHBG), and dehydroepiandrosterone (DHEA) in blood, in addition to urinary DHEA. Self-reports of testicular maturation showed no difference between settled and nomadic subpopulations. However, nomadic boys exhibited significantly higher levels of T, DHEA, and SHBG. Of all the hormones, only SHBG showed a significant relationship with age. Multiple regression models show blood T and SHBG to be significant independent predictors of achieved height as well as weight, controlling for age. Our results suggest that onset of puberty is substantially delayed among Turkana males, and that bioavailable T is related to growth in stature during adolescence. We suggest that SHBG acts to mediate the effects of energy availability on adolescent growth in this energetically limited population. Our findings may also have implications for understanding adolescent growth among Homo erectus. Am J Phys Anthropol 2005., © 2005 Wiley-Liss, Inc.
Acquired resistance to drugs targeting receptor tyrosine kinases

Development of resistance to chemotherapeutic drugs represents a significant hindrance to the effective treatment of cancer patients. The molecular mechanisms responsible have been investigated for over half a century and have revealed the lack of a single cause. Rather, a multitude of mechanisms have been delineated ranging from induction and expression of membrane transporters that pump drugs out of cells (multidrug resistance (MDR) phenotype), changes in the glutathione system and altered metabolism to name a few. Treatment of cancer patients/cancer cells with chemotherapeutic agents and/or molecularly targeted drugs is accompanied by acquisition of resistance to the treatment administered. Chemotherapeutic agent resistance was initially assumed to be due to induction of mutations leading to a resistant phenotype. This has also been true for molecularly targeted drugs. Considerable experience has been gained from the study of agents targeting the Bcr-Abl tyrosine kinase including imatinib, dasatinib and sunitinib. It is clear that mutations alone are not responsible for the many resistance mechanisms in play. Rather, additional mechanisms are involved, ranging from epigenetic changes, alternative splicing and the induction of alternative/compensatory signaling pathways. In this review, resistance to receptor tyrosine kinase inhibitors (RTKIs), RTK-directed antibodies and antibodies that inactivate ligands for RTKs are discussed. New approaches and concepts aimed at avoiding the generation of drug resistance will be examined. The recent observation that many RTKs, including the IGF-1R, are dependence receptors that induce apoptosis in a ligand-independent manner will be discussed and the implications this signaling paradigm has on therapeutic strategies will be considered.
A general recursion method for calculating diffracted intensities from crystals containing planar faults

A general recursion algorithm is described for calculating kinematical diffraction intensities from crystals containing coherent planar faults. The method exploits the self-similar stacking sequences that occur when layers stack non-deterministically. Recursion gives a set of simple relations between average interference terms from a statistical crystal, which can be solved as a set of simultaneous equations. The diffracted intensity for a polycrystalline sample is given by the incoherent sum of scattered intensities over an ensemble of crystallites. The relations between this and previous approaches, namely the Hendricks-Teller matrix formulation, the difference equation method, the summed series formula of Cowley, and Michalski’s recurrence relations between average phase factors, are discussed. Although formally identical to these previous methods, the present recursive description has an intuitive appeal and proves easier to apply to complex crystal structure types. The method is valid for all types of planar faults, can accommodate long-range stacking correlations, and is applicable to crystals that contain only a finite number of layers. A FORTRAN program DIFFaX , based on this recursion algorithm, has been written and used to simulate powder X-ray (and neutron) diffraction patterns and single crystal electron (kinematical) diffraction patterns. Calculations for diamond-lonsdaleite and for several synthetic zeolite systems that contain high densities of stacking faults are presented as examples.
A continuous flow strategy for the coupled transfer hydrogenation and etherification of 5-(hydroxymethyl)furfural using Lewis acid zeolites.

Hf-, Zr- and Sn-Beta zeolites effectively catalyze the coupled transfer hydrogenation and etherification of 5-(hydroxymethyl)furfural with primary and secondary alcohols into 2,5-bis(alkoxymethyl)furans, thus making it possible to generate renewable fuel additives without the use of external hydrogen sources or precious metals. Continuous flow experiments reveal nonuniform changes in the relative deactivation rates of the transfer hydrogenation and etherification reactions, which impact the observed product distribution over time. We found that the catalysts undergo a drastic deactivation for the etherification step while maintaining catalytic activity for the transfer hydrogenation step. 119 Sn and 29 Si magic angle spinning (MAS) NMR studies show that this deactivation can be attributed to changes in the local environment of the metal sites. Additional insights were gained by studying effects of various alcohols and water concentration on the catalytic reactivity.
An inverse problem for a class of continuous distributions with skewness

An inverse problem pertaining a class of univariate continuous distributions with skewness is investigated. The Fourier transform and analytic characteristic functions are used to obtain the results.
Generalized Boundary Interactions for Powder Lubricated Couette Flows

Application of grain flow theories to powder lubrication of hydrodynamic bearings requires careful consideration of slip of the flow velocity at the boundaries together with appropriate formulation of the fluctuation (thermal) velocity conditions at the boundaries. Generalized boundary conditions that can be applied to a wide variety of surface and grain material characteristics are developed for a Couette flow configuration. The equations account for both the energy loss at the boundary due to inelastic grain-wall collisions and the energy supplied by the boundary due to collisional momentum supply. The predictions of the model are compared to a number of published results that are based on direct computer simulation of grain-grain collisions. The model's flexibility is demonstrated by simulating the effects of unequal surface roughnesses.
Fire Effects on Nitrogen Cycling in Native and Restored Calcareous Wetlands

Fire is an important natural process and management tool in the Florida Everglades, but few studies have examined its effects on nutrients; nitrogen (N) in particular has received little attention across the whole Everglades system. In this study, we investigated fire effects on the N cycle in both a high-phosphorus (P) restored wetland and a low-P reference calcareous wetland (marl prairie) in the Hole-in-the-Donut region of the southern Everglades. Potential N mineralization, denitrification, extracellular enzyme activities, and periphyton N2 fixation rates were measured immediately (two days), one month, and one year after a prescribed burn. Results showed differing responses of N cycle processes between the two sites: N availability increased immediately after the fire at the low-P reference site, but did not increase immediately at the high-P restored site. We also saw a greater increase in denitrification immediately after the fire in the reference site (118% increase) compared to only 20% increase in the restored site. Periphyton N2 fixation in the restored site tended to be stimulated, but was inhibited in the reference site after the fire. The underlying mechanisms for these changes are not clear, but fire residues (ash and char) may directly and indirectly affect the N cycle. These findings have implications for management of fire intensity in natural and P-impacted sites.
Enhancement of polycyclic aromatic hydrocarbons in estuarine invertebrates by surface runoff at a decommissioned military fuel depot

Abstract Accumulation of polycyclic aromatic hydrocarbons (PAHs) was determined in blue mussels ( Mytilus spp.) and shore crabs ( Hemigrapsus sp.) at a recently closed military fuel depot in central San Francisco Bay, California. In April 1996, during a period of above average precipitation, specimens were collected at the depot, near the depot, and at sites 10 and 20 km south of the depot. Four weeks after the rains ended, blue mussels were again collected at the depot, and at two additional sites in the central Bay region. In April, total PAHs in mussels from the depot were significantly higher only than that in mussels collected 20 km from the depot; however, seven specific, substituted PAHs were higher at the depot than at all other sites. In June, only two of the 38 PAHs common in mussels in April were detected at the depot; these concentrations were comparable to ambient concentrations in mussels at the Bay. It seemed that bioavailability of PAHs at the depot was enhanced by rainfall, probably due to the mobilization of PAHs via groundwater into the Bay. Concentrations in mussels from chronically contaminated sites were about five times higher than mussels collected from the depot. Low PAH concentrations were detected in shore crabs near the depot, and the highest levels were not associated with the depot. Observed PAH concentrations are discussed in relation to upper trophic organisms.
The mucocutaneous marker of pseudoxanthoma elasticum

A patient with angioid streaks discovered ophthalmoscopically was evaluated in the dermatology clinic for pseudoxanthoma elasticum (PXE). Cutaneous markers for PXE did not appear in the usual locations; mucosal involvement of the lower lip was the only clinically ascertainable clue. The presence of the disease was confirmed by histologic examination of the oral mucosa. This case stresses the importance of familiarity with the mucocutaneous markers of PXE by members of the dental profession.
Employment Status Among Parenting Teenage Mothers Enrolled in High School

BACKGROUND Many programs emphasize subsequent pregnancy prevention and high school graduation among teenage mothers; however, less is known about their ability to increase financial earnings from employment opportunities while concurrently enrolled in school. This study evaluates factors influencing employment status among teenage mothers after enrolling in a community-based randomized intervention. METHODS Project Mothers and Schools (PMAS) initiative participants were surveyed at baseline and 12 months after enrollment. The 56 control group participants received homebound education and family case management, whereas the 59 intervention group participants received these basic-level services as well as group parenting time, life skills, and leadership training. A generalized estimating equation was used to identify statistically significant changes associated with the intervention. RESULTS Participants were significantly more likely to receive money from their jobs at postintervention relative to baseline (OR = 4.75, p = .023); however, this change was not statistically significant when comparing the control group to the intervention group. At postintervention, those who received money from parents were significantly less likely to receive money from their job (OR = 0.12, p = .002). CONCLUSIONS While PMAS benefited participants in terms of employment, the role of parental support requires additional investigation to determine its influence on teenage mothers' ability to achieve financial independence.
Criteria for Optimizing Size and Configuration of Milk Pipelines

Abstract To verify various theoretical and practical aspects of milk flow, an experimental milk pipeline was used. Flow instability, characterized by a flooded section of pipeline (that is, formation of milk “slugs”), was dependent on pipeline configuration. Vacuum fluctuations from milk slugs as great fill depths characterized a looped configuration as 28.6 kPa were measured in a dead-end configuration. By contrast, stable flow over a wide range of flow rates, slopes, and. Manning's equation under stable flow conditions accurately predicted flow rate as a function of fill depth, slope, and pipe diameter. Milk Acid Degree Value was higher in milk subjected to slugging. An analysis of effective shear stress on milk suggests a range of fill depths for which milk quality might be maintained. A theoretical model is presented to predict pipeline milk flow as a function of number of cows and rate of unit attaching. A method for pipeline sizing is presented using this model, together with Manning's equation and suitable constraints for fill depth. Current recommendations for pipeline sizing may result in oversized pipeline diameters.
The HLA-DQβ gene upstream region contains an immunoglobulin-like octamer motif that binds cell-type specific nuclear factors

A method is described for scanning relatively large fragments of DNA for sequences which bind nuclear factors. This method was used to identify an octamer (ATTTGTAT) in the DQ beta gene upstream region which differs from the immunoglobulin gene octamer (ATTTGCAT) by only 1 bp. The DQ beta gene octamer binds two proteins, one (B2) appears to be B cell specific while the other (B1) is not. These factors are either similar or identical to factors which bind to the octamer motif in immunoglobulin genes. All other class II MHC genes for which sequence information is available contain an octamer motif in their upstream region. Thus, the possibility that these sequences regulate B cell specific expression of class II MHC genes requires careful evaluation.
Imaging quality determines differences in reading performance and perceived image quality with CRT and hard-copy displays

The effects of physical image quality on reading and on perceived image quality from CRT and hard copy displays (photographs) were studied. The results showed that as the image quality of a display increased, indicated by an increase in the value of the modulation transfer function area (MTFA), the reading speed and subjective image quality ratings increased. This change in reading speed and perceived image quality occurred similarly for both hard-copy and soft-copy conditions. If the image qualities of the displayed text are similar, hard-copy and soft-copy displays will yield equivalent reading speeds. Language: en
Computing Two-Fluid Models of Compressible Water-Vapour Flows with Mass Transfer

This paper is devoted to the simulation of water-vapour flows with mass transfer, using the two-fluid approach proposed in 8, 11,12,17,22,23,27 . The two-fluid model contains stiff source terms associated with pressure-velocity-temperature-Gibbs potential relaxation terms, and the convective part of the model is highly non linear and has no conservative form. Thus the computation of the whole model is rather difficult, and it requires the development of specific algorithms. Actually, a rather slow rate of convergence of schemes with respect to the mesh size is expected for convection-dominated flow computations (more precisely h -respectively hfor so-called first-order -respectively second-orderschemes) , due to the occurence of several contact discontinuities, and the reader is refered to references 7, 9, 13,25,26,28,30,31 for instance, which examine in detail the behaviour of several Riemann solvers and relaxation techniques in order to cope with the convective part of the two-fluid model. Moreover, small time scales in relaxation source terms render the computation even more tricky, and some attempts to deal with pressure-velocity-temperature relaxation effects have been recently reported in . One difficulty is connected with the computation of pressure relaxation effects, since it requires a tight coupling of source terms in energy and statistical void fraction equations. The accurate computation of gas-liquid flows with no mass transfer is not easy, but water-vapour flow simulations that account for mass transfer are clearly even more difficult, and emphasis is given here on this topic.