cssi/SciSciGPT-SciSciNet huggingface dataset:
Histopathology of the prefrontal cortex in major depression: what does it tell us about dysfunctional monoaminergic circuits?

Publisher Summary This chapter discusses the prefrontal cell pathology in major depression as it relates to biochemical and structural changes detected in studies of the serotonergic and noradrenergic neurons located in the brainstem. Information pertaining to both current and lifetime psychiatric symptoms was gathered using the schedule for affective disorders and schizophrenia. State-of-the-art morphometric and stereological methods were used to assess neuronal and glial cell densities, cell body size and cortical thickness in each of the three prefrontal regions. The validity of studies described is underscored by the fact that the tissues from the prefrontal cortex and brainstem nuclei were examined in the same depressives and control subjects. The cellular changes described in these postmortem studies indicate that both types of brain cells, neurons and glia, are involved in the cortical pathology of major depression. It remains to be determined whether the morphometric changes detected postmortem in subjects with major depressive disorder are trait or state dependent, and whether antidepressant medications have an effect on cell morphology. In the present study, cell pathology was detected even in those subjects who were not taking antidepressant medications; however, further behavioral and morphometric experiments on animals treated with antidepressant medications will shed more light on this issue.
Suggested guidelines for studying the combined effects of occupational exposure to noise and chemicals on hearing

The present document, which describes recommended standardized procedures, aims to assist individual investigators plan a study on the effects of industrial chemicals on the auditory system, collect and analyze environmental and hearing sensitivity data that are accurate and comparable to data acquired by others. This draft document is currently being reviewed by the NoiseChem Research Group. In this peer review stage we are currently accepting critiques and suggestions to this proposal. Investigations on the aforementioned topic are necessary since there is strong evidence that occupational hearing loss may be caused not only by noise but also by exposure to certain chemicals in the work environment. Since some industrial chemicals are known to be ototoxic, it is plausible to expect that if these chemicals occurred in high enough concentrations in the workplace they could affect hearing. Laboratory studies have yielded a finding not expected, namely that when simultaneous exposure to noise and chemicals occur, the hearing loss observed was greater than the expected hearing loss from noise added to the expected hearing loss from the chemical. If this synergism is verified in humans, then changes will be required in the limits that are set for occupational hazards in order to prevent occupational hearing loss.
Characterization of reservoir simulation models using a polynomial chaos‐based ensemble Kalman filter

[1] Model-based predictions of flow in porous media are critically dependent on assumptions and hypotheses that are not always based on first principles and that cannot necessarily be justified on the basis of known prevalent physics. Constitutive models, for instance, fall under this category. While these predictive tools are usually calibrated using observational data, the scatter in the resulting parameters has typically been ignored. In this paper, this scatter is used to construct stochastic process models of the parameters which are then used as the cornerstone in a novel model validation methodology useful for ascertaining the confidence in model-based predictions. The uncertainties are first quantified by representing the unknown model parameters via their polynomial chaos decompositions. These are descriptions of stochastic processes in terms of their coordinates with respect to an orthogonal basis. This is followed by a filtering step to update these representations with measurements as they become available. In order to account for the non-Gaussian nature of model parameters and model errors, an adaptation of the ensemble Kalman filter is developed. Instead of propagating an ensemble of model states forward in time as is suggested within the framework of the ensemble Kalman filter, the proposed approach allows the propagation of a stochastic representation of unknown variables using their respective polynomial chaos decompositions. The model is propagated forward in time by solving the system of partial differential equations using a stochastic projection method. Whenever measurements are available, the proposed data assimilation technique is used to update the stochastic parameters of the numerical model. The proposed method is applied to a black oil reservoir simulation model where measurements are used to stochastically characterize the flow medium and to verify the model validity with specified confidence bounds. The updated model can then be employed to forecast future flow behavior.
Optical bistability in reflection-mode operation of a diode laser amplifier

Summary form only given. We report results of an experiment in which the output of a single-mode diode laser is injected into a diode laser amplifier operated close to its lasing threshold. The injected light is periodically modulated at frequencies very slow compared with the relevant relaxation frequencies within the amplifier. In contrast to most experiments, we operate the amplifier in a reflection mode instead of the transmission mode. Under the influence of the periodic modulation, the amplifier output exhibits several novel types of hysteresis and associated bistable behavior.
The physical chemistry of Criegee intermediates in the gas phase

Carbonyl oxides, also known as Criegee intermediates, are key intermediates in both gas phase ozonolysis of unsaturated hydrocarbons in the troposphere and solution phase organic synthesis via ozonolysis. Although the study of Criegee intermediates in both arenas has a long history, direct studies in the gas phase have only recently become possible through new methods of generating stabilised Criegee intermediates in sufficient quantities. This advance has catalysed a large number of new experimental and theoretical investigations of Criegee intermediate chemistry. In this article we review the physical chemistry of Criegee intermediates, focusing on their molecular structure, spectroscopy, unimolecular and bimolecular reactions. These recent results have overturned conclusions from some previous studies, while confirming others, and have clarified areas of investigation that will be critical targets for future studies. In addition to expanding our fundamental understanding of Criegee intermediates, the r...
Effect of cystine on the methionine requirement of healthy Indian men determined by using the 24-h indicator amino acid balance approach

Background: The 1985 FAO/WHO/UNU requirement for methionine in healthy adults consuming a cystine-free diet is 13 mg kg -1 . d -1 . It is unclear whether this daily requirement is influenced by dietary cystine. Objective: We assessed the effect of 2 intakes of cystine (5 and 12 mg . kg -1 . d -1 ) on methionine requirements in well-nourished Indian men by using 7 test methionine intakes (3,6,9,13,18,21 and 24 mg . kg -1 . d -1 ) and the 24-h indicator amino acid oxidation (24-h IAAO) and balance (24-h IAAB) methods. We combined these data with those from an experiment with zero cystine intake and in which the exact same method was used. Design: Two studies were performed in which a diet containing either 5 or 12 mg cystine . kg -1 . d -1 was fed to 21 well-nourished Indian men over three 7-d periods. The 24-h IAAO and 24-h IAAB values were measured on day 7 with the use of a 24-h intravenous [ 13 C]leucine tracer infusion. The breakpoints in the relation between these values and methionine intake in each study were assessed by two-phase linear regression. Results: Breakpoints in the response curve were obtained at methionine intakes of 20 (95% Fiellers CI: 17,26) and 10 (95% Fiellers CI: 8, 16) mg . kg -1 . d -1 with cystine intakes of 5 and 12 mg . kg -1 . d -1 intakes, respectively, which suggested a sparing effect of cystine. Although the 5- and 12-mg cystine breakpoints differed from one another, they did not differ significantly from that estimated previously with 0 mg cystine. Conclusion: Cystine may spare the methionine requirement in healthy men, although the amount of sparing is difficult to quantify.
Review of Stanislas Breton, A Radical Philosophy of Saint Paul. Trans. J. N. Ballan; introduction by W. Blanton; Insurrections: Critical Studies in Religion, Politics, and Culture; New York: Columbia University Press, 2011

This is a book review of Stanislas Breton, A Radical Philosophy of Saint Paul. Trans. J. N. Ballan; introduction by W. Blanton; Insurrections: Critical Studies in Religion, Politics, and Culture; New York: Columbia University Press, 2011
Climate Change and Soil Erosion Risks

The widely recognized global climate change is attributed mostly to anthropogenic activities which are the leading sources of greenhouse gases (GHGs) (IPCC, 2007). The current concentration of atmospheric GHGs is the highest level since 650,000 yr (IPCC, 2001). Principal GHGs, both natural and synthetic, are listed in Table 20.1. Global warming potentials (GWPs) are often used to compare the abilities of GHGs to trap heat and warm the atmosphere. The GWPs are estimated from the heatabsorbing ability and the decay rate of each GHG with respect to CO2.
Creativity and the Home Environment

Home environments of highly creative and less creative boys were studied through 150 question semi-structured interviews with 86 mothers. Interview responses, categorized along 24 dimensions, revealed significant differences related to parental creativity, independence and flexibility, emotional distance, and differential parental patterning.
A linear programming scheme for IPS traffic scheduling

Intrusion Prevention System (IPS) sensors represent the initial security barrier of a network. A main challenge in today's Internet environment is the amount of traffic these devices have to inspect. This paper presents a linear program for traffic scheduling in multi-sensor environments that alleviates inspection load at sensors. The model uses a per-flow alarm rate metric which quantifies the ratio of the amount of traffic that matches the configured signatures to the amount of traffic inspected. Traffic flows can be classified based on the metric, which permits the efficient use of computational resources to inspect suspicious traffic. Numerical results demonstrate how the proposed model can be used in enterprise networks. While the linear program is not constrained to integral solutions, traffic flows are mostly scheduled for inspection to a single sensor, which facilitates the collection of state information. This feature is essential to detect malicious traffic characterized by composite signatures.
Cryopreservation Prevents Arterial Allograft Dilation

Historically, immune-mediated degradation and subsequent aneurysm formation have limited the usefulness of cryopreserved arterial allografts. This study tested the hypothesis that modern cryopreserved arterial allografts are protected from immune-mediated dilation. Abdominal aortas were harvested from anesthetized rats (Lewis and Brown-Norway) for immediate implantation or cryopreservation. Subsequently, Lewis rats underwent infrarenal aortic replacement with either an acutely harvested or a cryopreserved graft. There were four experimental groups: (1) acutely harvested isografts (Iso; n = 6), (2) cryopreserved isografts (C-Iso; n = 6), (3) cryopreserved allografts (C-Allo; n = 6), and (4) acutely harvested allografts (Allo; n = 6). All grafts were explanted at 8 weeks. A video camera and edge detection software were used to measure systolic and diastolic in vivo graft diameter ( d ). Measurement of arterial blood pressure (p) allowed calculation of compliance (δ d /δp). Tall-cuff plethysmography was used to assess graft patency at 1 week. Graft diameter and blood pressure measurements were repeated at harvest. All harvested grafts were examined histologically. Our results showed that cryopreservation prevented immune-mediated dilation in arterial allografts in our 8-week rat implant model. Furthermore, the compliance of the cryopreserved grafts and was similar to that of controls. Further investigation is needed to delineate the exact mechanism of these potential cliniclly significant findings.
Numerical model for predicting and managing heat dissipation from a neural probe

Use of stimulating neural probes has increased in an effort to better understand neural pathways. Current designs using light as a stimulating impulse externally couple the light into the probe. Relocating the light source to the probe tip would improve the flexibility of the technique; however, this approach would generate heat within the embedded probe. Minor temperature excursions can easily damage tissues under study, creating inaccurate results and/or damaging the tissue. A model has been created using COMSOL for the thermal effects of these heated probes in the brain. The model includes blood perfusion and metabolic processes. The model was used to investigate the effect of different geometric parameters on the temperature excursion. It was observed that the maximum temperature change decreases with insertion depth and decreases as the heated area of the probe is increased. The model was also used to study the effect of extending the probe beyond the heated region. This resulted in a significant reduction in temperature excursion. The model has been experimentally validated through physical tests using an Agar gel as a neural tissue simulant.
Technology’s influence on physical activity and exercise science: the present and the future

Abstract Background and purpose. Research and application in the physical activity and exercise area are increasingly impacted by technology. The exponential growth of World Wide Web access and the proliferation of personal computers highlight the importance of this development. The purpose of this article is to discuss the current impact of technology on different aspects of physical activity interventions and potential future applications. Methods. Relevant literature is reviewed within each of the areas being discussed. Results and conclusions. Technology has contributed to a secular decline in physical activity; however, it allows a) the proactive recruitment of large populations, b) the individualization of interventions on a large scale, and c) the delivery of activity promoting interventions to large populations via differing channels. Support is emerging for individualized interactive physical activity interventions delivered to large samples. Yet-untested areas where technology may have a beneficial impact on physical activity adoption and maintenance are interactive TV and virtual reality. With the increased focus on environmental strategies, technology could also be used to modify home environments to facilitate incorporating physical activity into everyday life. Technology is also increasing its role in the business of physical activity/exercise. For example, web-based health sites are now listed on the stock market. Health and fitness centers are adopting high-tech entertainment capabilities to serve each client. Combining the individualized technology used in the adoption and maintenance research with the existing infrastructures in health and fitness centers could increase adherence within these centers. Currently, however, there is limited research and utilization of this technology for the promotion of physical activity and exercise at the population level.
Rice hull biocomposites. I. Preparation of a linseed-oil-based resin reinforced with rice hulls

Biocomposites consisting of a conjugated linseed-oil (CLO)-based thermoset reinforced with rice hulls were prepared by free-radical polymerization initiated by t-butyl peroxide. The resin composition was kept constant at 50 wt % CLO, 35 wt % n-butyl methacrylate, and 15 wt % divinylbenzene. Tensile tests, dynamic mechanical analysis, thermogravimetric analysis, Soxhlet extraction, and differential scanning calorimetry were used to establish the ideal cure sequence. The pressure during cure, filler load, and the drying and grinding of the filler were varied, and their effects on the final properties of the composites were assessed. Optimal conditions were established for the preparation of rice hull biocomposites. Scanning electron microscopy showed a weak filler–resin interaction and X-ray mapping suggested the presence of silica in the rice hulls; this have accounted for the high thermal and mechanical properties obtained for these composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
A Generalization of the T-Method of Multiple Comparisons for Interactions

Abstract Tukey's [4] T-(maximum modulus) method of multiple comparisons is applicable to homoscedastic and equally correlated normally distributed random variables. For multiple comparisons on interaction effects (in factorial experiments), the allied random variables are not equally correlated. Nevertheless, it is shown that the T-method holds in this situation. The theory is illustrated by an example on a partially balanced incomplete block (PBIB) design.
Repair of a genetically-caused defect in oogenesis in Drosophila melanogaster by transplantation of cytoplasm from wild-type eggs and by injection of pyrimidine nucleosides☆

Abstract Eggs produced by homozygous mutant rudimentary (r9, 154.5) females of Drosophila melanogaster die during embryogenesis, apparently because the mutant female fails to incorporate certain substances into the egg during oogenesis. These eggs can be rescued by injecting them at the preblastoderm stage with wild-type nuclei and cytoplasm or wild-type cytoplasm alone from unfertilized eggs. Some preblastoderm eggs injected with 1.5% of egg volume of cytoplasm from unfertilized wild-type eggs were able to complete both embryonic and postembryonic development and emerged as adults, whereas not a single uninjected control egg was able to complete embryonic development. The eggs of rudimentary mothers can also be rescued by injecting each egg at the blastoderm stage with 0.01 μg of pyrimidine nucleosides. The results demonstrate that a pyrimidine deficiency is the cause of abortive embryogenesis, and confirm the previous finding that the rudimentary mutation leads to pyrimidine auxotrophy.
Jungian dimensions of personality, subclinical depression and suicidal ideation

Abstract Current subclinical depression and prior suicidal preoccupation were examined for their association with Jungian dimensions of personality in normal college students. Depression scores were associated with introversion scores while prior suicidal preoccupation were associated with intuiting and perceiving scores.
Anaesthesia for patients after lung transplantation.

Purpose The purpose of this article is to review the literature on post lung transplant patients presenting for surgery and anaesthesia and to provide insight into their penoperatrve management
Gynemimesis and gynemimetophilia: individual and cross-cultural manifestations of a gender-coping strategy hitherto unnamed.

Abstract Gynemimesis is a subtype of gender transposition or gender dysphoria in which a person with male anatomy and morphology lives in society as a woman without genital sex-reassignment surgery, and with or without taking female sex-hormonal therapy. The lover of such a person is a gynemimetophile . The corresponding terms that apply to the female are andromimesis and andromimetophile . In most large cities of the West there exists an unnamed gynemimetic community that corresponds to the social institution of hijras in India and xanith in Oman. Clinicians can contribute to the rehabilitation and welfare of gynemimetic youth in society, by providing overall health care, including endocrine treatment and mental-health counseling.
Imaging of Neonatal Child Abuse with an Emphasis on Abusive Head Trauma

Child abuse and neglect is a serious clinical and socioeconomic problem that is sometimes underestimated. One of the most devastating forms is abusive head trauma. This review addresses the radiological workup in cases of suspected child abuse. The use of all modalities, and their advantages and disadvantages, is discussed. A special section is devoted to the radiological report in cases of child abuse, as a clinical record and a legal document.
Coupled deflection and rotation of anisotropic open-section composite stiffeners

Thin-walled open-section beams constructed of panels of laminated composite materials and subjected to transverse loading are considered in this paper. Such beams are used as stiffeners in stiffened-panel construction for aerospace vehicles and in composite structural frames for rotorcraft vehicles. Beams constructed of panels having generally anisotropic mechanical properties are considered. Due to anisotropically induced normal-shear coupling effects these open-section beams will rotate and deflect laterally out-of-plane under the action of in-plane transverse loads in addition to their expected transverse deflection. A one-dimensional modified beam theory is used to describe the coupled deflection and rotation of these beams. The theory, which is intended for preliminary design studies, can be used to obtain inexpensive 'hand-calculation' predictions of the behavior of anisotropic thin-walled beams. .Predictions of the theory are compared with predictions of a 3-D finite element analysis in which the beams are constructed of general laminated shell elements. Good agreement between the theory and the finite element results is shown.
Synthesis and characterization of injectable, biodegradable, phosphate-containing, chemically cross-linkable, thermoresponsive macromers for bone tissue engineering

Novel, injectable, biodegradable macromer solutions that form hydrogels when elevated to physiologic temperature via a dual chemical and thermo-gelation were fabricated and characterized. A thermogelling, poly(N-isopropylacrylamide)-based macromer with pendant phosphate groups was synthesized and subsequently functionalized with chemically cross-linkable methacrylate groups via degradable phosphate ester bonds, yielding a dual-gelling macromer. These dual-gelling macromers were tuned to have transition temperatures between room temperature and physiologic temperature, allowing them to undergo instantaneous thermogelation as well as chemical gelation when elevated to physiologic temperature. Additionally, the chemical cross-linking of the hydrogels was shown to mitigate hydrogel syneresis, which commonly occurs when thermogelling materials are raised above their transition temperature. Finally, degradation of the phosphate ester bonds of the cross-linked hydrogels yielded macromers that were soluble at physiologic temperature. Further characterization of the hydrogels demonstrated minimal cytotoxicity of hydrogel leachables as well as in vitro calcification, making these novel, injectable macromers promising materials for use in bone tissue engineering.
Endoscopic Treatment of Amyloidosis of the Nasopharynx

Amyloidosis of the nasopharynx is a rare presentation of localized amyloidosis. The majority of systemic amyloidosis cases involve the heart, gastrointestinal tract, kidneys, and upper and lower re...
Coupled Simulation of Hemodynamics and Vascular Growth and Remodeling in a Subject-Specific Geometry

A computational framework to couple vascular growth and remodeling (G&R) with blood flow simulation in a 3D patient-specific geometry is presented. Hyperelastic and anisotropic properties are considered for the vessel wall material and a constrained mixture model is used to represent multiple constituents in the vessel wall, which was modeled as a membrane. The coupled simulation is divided into two time scales-a longer time scale for G&R and a shorter time scale for fluid dynamics simulation. G&R is simulated to evolve the boundary of the fluid domain, and fluid simulation is in turn used to generate wall shear stress and transmural pressure data that regulates G&R. To minimize required computation cost, the fluid dynamics are only simulated when G&R causes significant vascular geometric change. For demonstration, this coupled model was used to study the influence of stress-mediated growth parameters, and blood flow mechanics, on the behavior of the vascular tissue growth in a model of the infrarenal aorta derived from medical image data.
Immobilization and release strategies for DNA delivery using carbon nanofiber arrays and self-assembled monolayers

We report a strategy for immobilizing dsDNA (double-stranded DNA) onto vertically aligned carbon nanofibers and subsequently releasing this dsDNA following penetration and residence of these high aspect ratio structures within cells. Gold-coated nanofiber arrays were modified with self-assembled monolayers (SAM) to which reporter dsDNA was covalently and end-specifically bound with or without a cleavable linker. The DNA-modified nanofiber arrays were then used to impale, and thereby transfect, Chinese hamster lung epithelial cells. This mechanical approach enables the transport of bound ligands directly into the cell nucleus and consequently bypasses extracellular and cytosolic degradation. Statistically significant differences were observed between the expression levels from immobilized and releasable DNA, and these are discussed in relation to the distinct accessibility and mode of action of glutathione, an intracellular reducing agent responsible for releasing the bound dsDNA. These results prove for the first time that an end-specifically and covalently SAM-bound DNA can be expressed in cells. They further demonstrate how the choice of immobilization and release methods can impact expression of nanoparticle delivered DNA.
Laparoscopic Radical Versus Partial Nephrectomy for Tumors >4 cm: Intermediate-term Oncologic and Functional Outcomes

OBJECTIVES To compare the oncologic and functional outcomes of laparoscopic radical nephrectomy (LRN) and laparoscopic partial nephrectomy (LPN) for clinical Stage T1b-T3 renal cell carcinoma >4 cm in size. METHODS This retrospective analysis compared patients undergoing LRN (n = 75) or LPN (n = 35) at a tertiary referral center from April 2001 to December 2005 for Stage T1b-T3N0M0 renal cell carcinoma. The endpoints included radiologically verified systemic and local recurrence, cancer-specific mortality, overall mortality, and chronic kidney disease as determined from the calculated glomerular filtration rate and Kidney Foundation Dialysis Outcomes Quality Initiative diagnostic criteria. RESULTS The LRN group had larger tumors (5.3 vs 4.9 cm; P = .03), more T3a tumors (33% vs 9%; P = .006), and more clear cell pathologic features (85% vs 66%; P = .03). No surgical margins in either group were positive. The median follow-up was 57 months (range 27-79) for the LRN group and 44 months (range 27-85) for the LPN group (P = .1). The overall mortality (11% vs 11%), cancer-specific mortality (3% vs 3%), and recurrence (3% vs 6%) rates (P = .4) were equivalent. The postoperative decrease in the estimated glomerular filtration rate was less in the LPN group than in the LRN group at 13 and 24 mL/min, respectively (P = .03). Postoperatively, 2-stage increases in the chronic kidney disease stage occurred in 12% vs 0% of patients in the LRN and LPN groups, respectively (P 4 cm, LPN provides equivalent oncologic efficacy and superior renal functional outcomes compared with LRN. Future studies are required to confirm these trends.
Simulated data sets for single molecule kinetics: some limitations and complications of data analysis

When the fluorescence intensity of a chromophore attached to or bound in an enzyme relates to a specific reactive step in the enzymatic reaction, a single molecule fluorescence study of the process reveals a time sequence in the fluorescence emission that can be analyzed to derive kinetic and mechanistic information. Reports of various experimental results and corresponding theoretical studies have provided a basis for interpreting these data and understanding the methodology. We have found it useful to parallel experiments with Monte Carlo simulations of potential models hypothesized to describe the reaction kinetics. The simulations can be adapted to include experimental limitations, such as limited data sets, and complexities such as dynamic disorder, where reaction rates appear to change over time. By using models that are known a priori, the simulations reveal some of the challenges of interpreting finite single-molecule data sets by employing various statistical signatures that have been identified.
MR-compatible ventilator for small animals: computer-controlled ventilation for proton and noble gas imaging.

We describe an MR-compatible ventilator that is computer controlled to generate a variety of breathing patterns, to minimize image degrading effects of breathing motion, and to support delivery of gas anesthesia and experimental inhalational gases. A key feature of this ventilator is the breathing valve that attaches directly to the endotracheal tube to reduce dead volume and allows independent control of inspiratory and expiratory phases of ventilation. This ventilator has been used in a wide variety of MR and x-ray microscopy studies of small animals, especially for MR imaging the lungs with hyperpolarized gases ( 3 He & 129 Xe). © 2000 Elsevier Science Inc. All rights reserved.
Carbon Nanotube Synthesis Using Mesoporous Silica Templates

Well-aligned carbon nanotubes (CNTs) were grown on mesoporous silica films by chemical vapor deposition (CVD). Ethylene was used as the carbon source and CVD was performed at 1023 K and atmospheric pressure. The films were doped with Fe during sol−gel synthesis, and three different structure directing agents were used for mesoporous silica preparation: polyoxyethylene (10) cetyl ether (C16EO10), Pluronic tri-block copolymer (P123), and cetyltriethylammonium chloride (CTAC). A high degree of CNT alignment on C16EO10 mesoporous silica films was produced at Fe:Si molar ratio of 1.80. Similar alignment of CNTs was achieved in the other preparations, but on CTAC-derived films CNTs only grew parallel to the substrate surface because the in-plane arrangement of the pore structure limited CNT growth to crack domains. We also show that the diameter of the CNTs can be controlled by changing the Fe concentration in the mesoporous silica substrate.
SU-FF-T-48: Dosimetric Feasibility of Using Low Energy Sources in Multi-Lumen Device for Partial Breast Brachytherapy

Purpose: To evaluate the dosimetric feasibility of using low energy sources (Cs‐131, I‐125, Pd‐103) in the multi‐lumen device for partial breast brachytherapy. The sources are placed into the device for multiple days until the desired dose is achieved, then withdrawn with the device. This outpatient procedure only requires two visits, one for source placement and another for device withdrawal. Method: A 10‐1 SAVI device was fully expanded, CT‐scanned and imported into VariSeed. Cavity, PTV (cavity + 1cm margin) and PTV_eval (PTV − cavity) were created. The same type and activity of seeds were added into the multi‐lumen device to cover the PTV_eval and seed activity was adjusted to achieve a nominal dose (50Gy in one half‐life of source). Different seed types and distributions were tested. Oncentra Brachy and IPSA optimization was used to generate a HDR plan for comparison. Dosimetric parameters (D90, V100, V150, and V200 of PTV_eval) and skindose were compared. Results: D90, V100, V150, and V200 of PTV_eval of HDR plan are 107%, 97%, 52cc, and 24cc. The most comparable LDR plan is from a non‐uniform distributed 90 3.2U Cs‐131 source, which gives 102%, 92%, 52cc, and 26cc. Skindose is lower than the HDR plan by ∼10% of the prescription dose from 0.5 ∼ 5 cm away from the PTV edge. With the comparable coverage, I‐125 gives slightly higher V150 and V200 (56cc and 30cc, respectively), while Pd‐103 gives much higher V150 and V200 (66cc and 46cc respectively). Conclusion: Cs‐131 is the best choice among the 3 commercially available low energy sources. It can provide adequate target coverage and similar dose homogeneity compared to HDR dosimetry in reasonable days (10 days). The faster dose fall‐off of the low energy sources give it advantage of less dose to the surrounding healthy tissues including skin,heart, and lung.
Changing the Minds of New College Students

With the unprecedented expansion of access to higher education internationally, today’s students enter university with a broader range of expectations, motivations and support networks than their predecessors. One of the primary determinants of student success is their ability to assimilate into the academic culture, which includes aligning their expectations and motivations closely with the prevalent norms of the academic community. This article synthesizes current conceptual and practical approaches to facilitating the assimilation of students from diverse demographic, economic and academic backgrounds into the academic community. These approaches are illustrated through programmatic developments at a large urban university in the Midwestern United States.
What Is an “Expert Student?”

This article suggests that conventional methods of teaching may, at best, create pseudo-experts—students whose expertise, to the extent they have it, does not mirror the expertise needed for real-world thinking inside or outside of the academic disciplines schools normally teach. It is suggested that teaching for “successful intelligence” may help in the creation of future experts. It is further suggested that we may wish to start teaching students to think wisely, not just well.
Intravenous infusion of gastrin-releasing peptide-27 and bombesin in rats reveals differential effects on meal size and intermeal interval length

We have previously shown that the intraperitoneal (i.p.) administration of gastrin-releasing peptide-27 (GRP-27) or bombesin (BN) (at 0.21, 0.41 and 1.03nmol/kg) reduces meal size (MS) and prolongs the intermeal interval (IMI). Here, we hypothesized that the intravenous (i.v.) administration of the same doses of GRP-27 and BN will be as effective as the i.p. administration in evoking these feeding responses. To test this hypothesis, we administered GRP-27 and BN i.v. and measured first MS (10% sucrose), IMI, satiety ratio (SR, IMI/MS) and second MS in overnight food-deprived but not water-deprived male Sprague Dawley rats. We found that (1) only GRP-27 reduced the first MS, (2) BN prolonged the IMI, (3) GRP-27 and BN increased the SR and (4) only BN reduced the size of the second meal. Contrary to our hypothesis, the i.v. administration of GRP-27 and BN affected the MS and IMI differently than did the i.p. administration. In conclusion, this pharmacological study suggests that the MS and IMI are regulated at different sites.
Summer Interns: Our Responsibility

Internships give students a chance to gain work experience, determine whether their interests fit a given area or organization, and create networks of contacts in the field. A senior manager's job involves succession planning, and where better to start than with summer interns? Consider what you want them to know and achieve to be successful in your office and perhaps even take over some day. It's up to the senior manager to teach them office etiquette, manners, and behavior during their internships. It's a boss's job with all employees, including interns, to empower them to succeed. As senior leaders, we must remember that part of leadership is doing just that, leading people, including new interns.
Exogenous Interferon protects Mice against Plasmodium berghei Malaria

WE have shown previously that several inducers of interferon protect mice against Plasmodium berghei malaria and that this protection is far greater against sporozoite-induced infections than against blood form-induced infection1–3. Others have reported that prolonged incubation of parasitized red blood cells (RBC) with serum containing interferon in vitro decreased or abolished the capacity of these cells to initiate lethal malarial infection in mice4. Another group found, however, that interferon had no effect on the development of malaria parasites in RBC in vitro (personal communication from T. Merigan). We show here that exogenous mouse serum interferon protects mice against sporozoite-induced Plasmodium berghei malaria.
A Stereooontrolled Approach to Tri and Tetrasubstttuted Cyclohexanones

Abstract A series of reactions utilizing acetals 2–5 with organo cuprates was studied to determine the stereoselectivity of the 1,4-conjugate addition. A90:10 stereoselectivity was observed from the reaction of lithium or bromomagnesium divinyl cuprate with acetal 5 which generated a facile entry to the tetrasubstituted cyclohexanone via a consecutive 1,4-conjugate addition - 1,3-alkylation sequence.
An overview of the chemistry and biology of reactive aldehydes

The nonenzymatic free radical generation of reactive aldehydes is known to contribute to diseases of sustained oxidative stress including rheumatoid arthritis, atherosclerosis, neurodegeneration, and a number of liver diseases. At the same time, the accumulation of lipid electrophiles has been demonstrated to play a role in cell signaling events through modification of proteins critical for cellular homeostasis. Given the broad scope of reactivity profiles and the ability to modify numerous proteomic and genomic processes, new emphasis is being placed on a systems-based analysis of the consequences of electrophilic adduction. This review focuses on the generation and chemical reactivity of lipid-derived aldehydes with a special focus on the homeostatic responses to electrophilic stress.
Digitonin incubation of spinach chloroplasts in tris (hydroxymethyl) methylglycine solutions of varying ionic strengths.

Abstract Spinach chloroplasts were incubated with digitonin in various media and the resulting derived fractions separated by differential centrifugation. (1) In low-salt-Tricine, the centrifugal fractions had the same chlorophyll composition as chloroplasts. All were active in the Hill reaction with ferricyanide or NADP+ and no separation of the two photosystems of photosynthesis was observed. The small particles, however, had enhanced rates of NADP+ photoreduction with ascorbate as electron donor. The fractions obtained were similar to sonicated chloroplast fragments. Electron micrographs of chloroplasts in low-salt-Tricine showed a marked difference from the usual chloroplast structure. The membrane system was discernible, but there was a marked breakdown of the original tight grana structure. The fixing properties were somewhat altered. (2) By contrast, in high-salt-Tricine, or ionic buffers (phosphate or Tris) only the large particles (low chl a chl b ) were active in the Hill reaction. The smaller particles (high chl a chl b ) photoreduced NADP+ at high rates, but both 2,6-dichlorophenolindophenol and ascorbate were required for maximal activity. These treatments resulted in a fractionation of the two photosystems. Electron micrographs of chloroplasts suspended in high-salt-Tricine or phosphate buffer show the usual membrane structure with intact grana. (3) Lyophilized chloroplasts gave fractions whose properties were also dependent on the ionic strength of the medium used for digitonin incubation. The Hill reaction rates were lowered, but NADP+ reduction with artificial electron donors was unimpaired by lyophilization.
Simulated Treatment of Recurrent Choroidal Neovascularization in Primate Retina: Comparative Histopathologic Findings

• We simulated the treatment of recurrent choroidal neovascular membranes (CNVM) by applying two courses of laser treatment to monkey retinas. Argon green, argon blue-green, and krypton red lasers (KRLs) were used in juxtafoveal, papillomacular bundle, and nonmacular areas. The effects were examined clinically and histopathologically. Results of once-treated control eyes were consistent with those of previous studies. Repeat treatment, however, resulted in full-thickness retinal destruction or necrosis with all laser modalities and in all fundus locations. These results are consistent with the absorptive characteristics of xanthophyll and melanin and suggest only limited advantages to the KRL when treatment of recurrent CNVM is performed in a previously treated area of the fundus. However, treatment of recurrent CNVM is still probably most successful with a KRL, because recurrent CNVM is usually at a border of a photocoagulation scar, where the retina is still untreated, and because histologic studies have demonstrated inner retinal sparing with a KRL in juxtafoveal areas.
Spherical flaw instability in hydrostatic tension

Fracture initiation due to a hydrostatic tensile stress field is studied by considering an idealized solid containing a small spherical cavity. Finite elastic deformation theory assuming Neo-Hookean material behavior is combined with an energy criterion to determine the critical cavity and applied stress at instability. It is found that the critical stress is a monotonically increasing function of a parameter, k = 6T/Eao, that is proportional to specific surface energy and inversely proportional to initial cavity size and modulus. For large cavities, the critical applied stress has the familiar Griffith form pc (k → 0) + (/43) (ET/ao)1/2, while for small cavities the critical stress tends to a constant pc (k →) = 2T/ao. Some final comments pertain to the relation between applied stress and local stress and strain at the point of fracture.
An ultrafast X-ray detector system at an elliptically polarizing undulator beamline

An ultrafast x-ray detector system is under development atLawrence Berkeley National Laboratory (LBNL) for application primarily tostudyies of ultrafast magnetization dynamics. The system consists of a fslaser, an x-ray streak camera and an ellipitically polarization undulator(EPU) beamline. Polarized x-rays from an EPU can be used to measure x-raymagnetic circular dichroism (XMCD) of a sample. XMCD has the uniqueability to independently measure orbit and spin magnetization withsub-monolayer sensitivity and element specificity. The streak camera hassimultaneously a sub-picosecond temporal resolution and a high spatialresolution. The combination of the streak camera and EPU allows us tostudy the transfer of angular momentum from spin to orbit to the latticein the sample on an ultrafast time scale. We describe here theperformance of the ultrafast detector, the laser and the x-raysynchronization system. The observation of the demagnetization process ofdifferent samples demonstrates the ability of the apparatus.
Vedernikov's criterion for ultra‐rapid flow

A criterion is given for the stability of steady uniform flow in open channels. When this number exceeds one, the flow is ultra-rapid, roll waves form, and the flow cannot be steady. This criterion is compared with several which have been proposed, and is judged to be more comprehensive and exact. An empirical formula for Chezy's “C” in ultra-rapid flow is derived from data already published by the author.
MacMahon's partition identity and the coin exchange problem

One of MacMahon's partition theorems says that the number of partitions of n into parts divisible by 2 or 3 equals the number of partitions of n into parts with multiplicity larger than 1. Recently, Holroyd has obtained a generalization. In this short note, we provide a bijective proof of his theorem.
Further evidence of a latitude gradient in the solar wind velocity

Simultaneous Mariner and Explorer data are used in the present paper to show that the large-scale gradient in the bulk velocity of the solar wind observed by Coles (1972) is a heliographic latitude gradient. A value of roughly 15 km/sec/deg for the gradient is derived by a correlation technique employed by Coleman and Rosenberg (1971). A simple model of the velocity/latitude dependence is developed and is shown to be consistent with a direct comparison of the observed Mariner and Explorer velocities. The gradient inferred from the Mariner and Explorer data is compared with values obtained from corresponding analyses of Vela and IPS data.
The observation of a picosecond transient in the relaxation of an iron porphyrin

Abstract Iron(III)tetraphenylporphyrin chloride, excited at 353 nm, showed significant bleaching and new absorption at 445 and 55 550 nm, which relaxed in 50 ps. Ground-state recovery occurs in ≲100 fs; the bottleneck is populated with 3% efficiency. The photoproduct spectrum resembles a porphyrin ππ * triplet, and provides evidence for intersystem crossing in an iron heme.
Points of local nonconvexity, clear visibility, and starshaped sets in Rd

Let S be a compact, connected, locally starshaped set in Rd, S not convex. For every point of local nonconvexity q of S, define Aq to be the subset of S from which q is clearly visible via S. Then ker S = ∩{conv Aq: q ∈ lnc S}. Furthermore, if every d+1 points of local nonconvexity of S are clearly visible from a common d-dimensional subset of S, then dim ker S = d.
Coupled Batchelor flows in a confined cavity

Steady, inviscid, incompressible two-dimensional flow in a quarter-circular cavity containing two vortex patches is investigated. A two-parameter family of solutions, characterized by any two out of the positions of the separation and reattachment points of the main eddy, the tangential velocity at separation and the ratio of the core vorticities, is identified and computed numerically. It is found that solutions can only be obtained for a rather narrow band of combinations of these parameters; the reasons for this constraint are discussed. Finally, we consider whether any of the coupled Batchelor flow solutions actually does represent the limit of high Reynolds number flow by comparing the inviscid results with those of earlier Navier–Stokes computations (Vynnycky & Kimura 1994). Agreement for the position of the dividing streamline and the location of the centre of the main core proves to be very encouraging, and suggestions are made as to the possible future development of such a two-eddy model.