cssi/SciSciGPT-SciSciNet huggingface dataset:
Toil and trouble? Growing the physician supply.

Richard Cooper outlines several obstacles to increasing the supply of U.S.-trained physicians. His analysis paints a bleak picture, but he may be underselling the possible benefits of technological advances that could increase medical school capacity and of increasing the volume of qualified applicants by broadening eligibility criteria. Another issue that would confront medical educators is that imbalances between supply and demand would not be uniform across states. This development could signal increased involvement from state policymakers, but public and private policymakers should take steps to assure that resources are funneled to where doctors are needed most and to exploit opportunities for innovative curriculum development.
Enhanced light scattering from the metal/solution interface: Chemical origins

Abstract Anomalous enhancement of the Raman intensity from pyridine and cyanide adsorbed onto metals has been investigated with particular attention to the role of surface chemistry. We have correlated the current-voltage characteristics of the Ag/cyanide system with the appearance and disappearance of the enhancement. We have chemically modified Au by sub-monolayer deposits of Ag to provide sites through which pyridine Raman scattering is enhanced under excitation conditions that normally show no enhancement. Comparison of cyanide etfects on Ag electroreflectance with the enhanced cyanide Raman scattering has shown that two distinctly different forms of adsorbed cyanide exist, only one of which is giant Raman active. We conclude from these experiments that a particular chemical bond between the molecule and the substrate is the most important prerequisite for enhanced scattering.
A New Series of X-Ray-Opaque Reinforcing Fillers for Composite Materials

Clear, colorless glasses that absorb roentgen rays were prepared by melting together compounds yielding silica, barium oxide, boric oxide, and alumina. Barium oxide made the glasses radiopaque and gave the desired refractive index. Boric oxide lowered the melt viscosity, and alumina tended to stabilize the glasses. Some of these glasses seem to be suitable for use as the reinforcing fillers for composite dental restorative materials.
Compression molding using a generalized eulerian–lagrangian formulation with automatic remeshing

A generalized Eulerian-Lagrangian approach is used to study the compression molding of viscoelastic polymers. The complete, unsteady, two-dimensional equations of motion are used in the analysis. The White–Metzner model is used to describe the constitutive behavior of the material. The solution is obtained using a mixed Galerkin finite element method. An automatic remeshing scheme is introduced to reduce the mesh distortion during the solution procedure. Results for the pressure and force required in mold closing are presented for the isothermal filling of a rectangular cavity. © 1992 John Wiley & Sons, Inc.
Do Presidential Debates Contribute to a Change in Voters' Attitudes?:

Summary.-A group of 36 undergraduates watched the second presidential debate of 1992 between Bush, Clinton, and Perot and completed pre- and posttest measures on voting preference. Analysis showed a significant difference between the pretest and posttest in terms of support for Clinton, with increased support by women already favorable.
Analogues of Poly(l-phosphoserine) via Living Polymerization of Phosphonate-Containing N-Carboxyanhydride Monomers

We have synthesized new phosphonate-containing α-amino acid N-carboxyanhydride (NCA) monomers and used these to prepare well-defined phosphonate-containing polypeptides and block copolypeptides. These NCAs were found to undergo living polymerization to high molecular weights with narrow chain length distributions. The methods described here demonstrate that phosphono polypeptides are also readily incorporated into block copolymers with controlled architecture and composition. One polymer, poly(l-phosphonohomoalanine) (poly(Pha)), is an isosteric analogue of poly(l-phosphoserine) and was found to display a pH-responsive conformational change. The pH-responsive α-helical conformation of poly(Pha) is unprecedented and may prove to be useful in the preparation of stimuli-responsive block copolypeptides containing poly(Pha) segments.
The evolution of attitudes to the human hazards of ionizing radiation and to its investigators.

Hanford Works, Richland, Washington, was one of the largest atomic plants in the United States. Several tens of thousands of persons employed at that site have been followed over four decades. Impressive as this number may seem at first sight, the Mancuso/Stewart/Kneale team consider it too small to estimate a cancer risk even 10 times as large as the low level radiation estimate produced by the International Commission on Radiation Protection [Stewart and Kneale, 1981]. It has been estimated [Stern, 1981] that a population 10–100 times the size would be required, even employing sophisticated techniques of analysis.
Tissue microarray evidence of association between p16 and phosphorylated eIF4E in tonsillar squamous cell carcinoma.

Background. Expression of p16 is a marker for human papillomavirus (HPV)-related carcinogenesis in head and neck cancer. The purpose of this study is to determine if p16 immunoreactivity is associated with aberrant expression of components of the PI3 kinase pathway. Methods. A tissue microarray (TMA) was constructed for 46 archived tonsillar squamous cell carcinoma specimens. Clinical demographics of these patients were analyzed, and the TMA was interrogated with antibodies directed against p16, phosphorylated AktSer473, phosphorylated S6Ser240/244, phosphorylated S6Ser235/236, phosphorylated 4E-BP1Thr37/46, phosphorylated eIF4ESer209, PTEN, p21, and p53. Results. There was a significant correlation between history of tobacco abuse (>10 pack/years) and absence of p16 expression (p = .01). Expression of p16 was significantly associated with immunoreactivity of p21 (p = .02), PTEN (p = .02), and phosphorylated eIF4E (p = .03). There was no evidence of association between p16 status and expression of phosphorylated S6, phosphorylated 4E-BP1, or p53. Conclusion. p16 positive tonsillar squamous cell carcinoma is characterized by expression of phosphorylated eIF4E that may occur via a mammalian target of rapamycin (mTOR)-independent mechanism. © 2010 Wiley Periodicals, Inc. Head Neck, 2010
An experimental analysis of self-thinning in juvenile steelhead trout

Mobile animal populations have been proposed to decline in density according to a slope based on the allometry of metabolic requirements or space requirements. In salmonid fishes, metabolic rate and food consumption scale to body mass by the exponent 0.87 and 0.73, respectively; whereas the territory size of steelhead trout scales to body mass by the exponent 0.86. Experimental cohorts of juvenile steelhead trout (Oncorhynchus mykiss) were used to test the hypothesis that mobile animal populations composed of individuals with indeterminate growth decline in density as a result of self-thinning. After controlling for experimentally manipulated levels of food abundance and stocking density, cohorts of steelhead trout declined in density with increasing body size according to a slope closest to the allometry of food consumption. Densities of steelhead trout were inversely related to average mass by the exponent −0.74. Despite the similarity to the food consumption slope, a relatively wide confidence interval also precluded distinguishing the slope either the metabolic rate or territory size slopes. Data from the literature were also examined to determine if there was general support for the idea of self-thinning in natural populations of stream-dwelling salmonid fish. Although not all data suggest that populations of salmonids in streams decline as a result of density-dependent intraspecific competition, at least some appear to fit the idea of self-thinning; especially when density is above a minimum level of habitat saturation.
Opposing roles of mGluR8 in measures of anxiety involving non-social and social challenges.

Metabotropic glutamate receptors (mGluRs) modulate glutamatergic and GABAergic neurotransmission. mGluR8, a member of group III receptors, is generally located presynaptically where it regulates neurotransmitter release. Previously we reported higher measures of anxiety in 6- and 12-month-old mGluR8−/− male mice than age- and sex-matched wild-type mice and that acute pharmacological stimulation with the mGluR8 agonist (S)-3,4,-dicarboxyphenylglycine (DCPG) or the Positive Allosteric Modulator (PAM) AZ12216052 reduced measures of anxiety in wild-type mice. As in humans and animals, ageing is associated with enhanced measures of anxiety following non-social and social challenges, increased understanding of these measures and how to potentially modulate them is particularly important in the elderly. Here we determined whether the effects of AZ12216052 on measures of anxiety are mediated by mGluR8 using 24-month-old mGluR8−/− and wild-type male mice. AZ12216052 also reduced measures of anxiety in the elevated zero maze and the acoustic startle response in mGluR8−/− mice. The remaining anxiolytic effects of AZ12216052 in mGluR8−/− mice might involve mGluR4, as the mGluR4 PAM VU 0155041 also reduced measures of anxiety in wild-type mice. In contrast, mGluR8−/− mice show enhanced social interaction but AZ12216052 does not affect social interaction in wild-type mice. Thus, while mGluR8 is an attractive target to modulate measures of anxiety and social interaction, the effects of AZ12216052 on measures of anxiety likely also involve receptors other than mGluR8.
The Illusion of Improved Physical Fitness and Reduced Mortality

WILLIAMS, P. T. The Illusion of Improved Physical Fitness and Reduced Mortality. Med. Sci. Sports Exerc., Vol. 35, No. 5, pp. 736–740, 2003. Purpose: To conduct a computer simulation to assess the effects of measurement error on prospective epidemiological studies that attribute mortality outcomes to apparent changes in the independent variable (e.g., physical fitness or activity) at baseline. Methods: As an example, we evaluated the design of the Aerobics Center Longitudinal Study (ACLS). This study compared apparent changes in fitness between two baseline visits to mortality during a subsequent 5-yr follow-up period. Unfit men who were reclassified as fit at the second baseline examination (6.6% of sample) and fit men who were reclassified as unfit (2.3%) had follow-up mortality rates that were between those of men who were consistently classified as fit or unfit. This study design was simulated assuming that differences between baseline treadmill test durations were due to measurement error alone. Based on our own data, we estimated that repeat measurements of treadmill test duration have correlation of r = 0.89 in the absence of any real fitness change. Results: There is excellent agreement between the published ACLS risk reductions and our simulated reductions for both cardiovascular disease (CVD) and total mortality. Compared with the “Unfit->Unfit” (the referent group), the estimated relative risks from the simulations for men who were reclassified as fit (i.e., “Unfit->Fit”) were 0.57 for total mortality and 0.52 for CVD mortality, and for men who remained classified as fit (“Fit->Fit”), they were 0.33 for total mortality and 0.20 for CVD mortality. Conclusion: The imprecision of the fitness measurement alone (i.e., measurement error) is sufficient to produce the reported ACLS risk reductions in initially unfit men who get reclassified as fit in a subsequent clinic visit. This statistical artifact will apply to other studies that use this design.
A time-resolved method for nonlinear ultrasonic measurements.

Abstract We describe a time-resolved method for measuring nonlinear ultrasonic phenomena. Current approaches rely on a narrowband measurement of harmonic generation to identify and characterize nonlinearity. Concomitant with these techniques is poor time resolution. We address this limitation with a hybrid narrowband/broadband approach that provides simultaneous time resolution and harmonic isolation for the measurement of weak nonlinearites. We discuss applications and present demonstrative results showing harmonic generation both in water and at a dry contact aluminum–aluminum interface.
Hormonal influences on the differentiation and growth of embryonic mouse mammary glands in organ culture

Abstract The action of estradiol, progesterone, growth hormone, mammotropin, and cortisol has been tested on the differentiation and growth of the embryonic mouse mammary gland in organ cultures maintained on a synthetic nutrient. Estradiol and progesterone inhibit the growth of the mammary epithelium. Estradiol stimulates the adipose tissue, and ground substance and connective tissue are eliminated as an effect of progesterone. Growth hormone and mammotropin promote an active growth of the mammary epithelium. However, mammotropin acts more specifically on the adipose tissue. Cortisol conditions the gland for secretion, inducing the distension of ducts to form alveoli and a hyperactivity of the adipose tissue.
Identification of a Hormonally Regulated Luteinizing Hormone/Human Chorionic Gonadotropin Receptor mRNA Binding Protein INCREASED mRNA BINDING DURING RECEPTOR DOWN-REGULATION

To elucidate the molecular events associated with the regulation of luteinizing hormone/human chorionic gonadotropin (LH/hCG) receptor mRNA stability during hCG-induced receptor down-regulation, we have identified an LH/hCG receptor-specific mRNA binding protein. Proteins were isolated from control and down-regulated rat ovary and were incubated with in vitro transcribed RNAs corresponding to the full-length LH/hCG receptor, as well as 5'- and 3'-truncated receptor forms. Resultant ribonucleoprotein complexes were analyzed by RNA gel mobility shift. A prominent Mr 50,000 ribonucleoprotein complex was identified with the following characteristics: 1) specificity for LH/hCG receptor open reading frame sequences located between nucleotides 102 and 282; 2) lack of competition by nonspecific RNAs; 3) a 3-fold increase in RNA binding activity during hCG-induced receptor down-regulation; and 4) limited tissue expression. This report describes the first evidence of an LH/hCG receptor mRNA binding protein, which we term LRBP-1, for luteinizing hormone receptor RNA binding protein-1. This protein is a candidate for a trans-acting factor involved in the hormonal regulation of LH/hCG receptor mRNA stability in rat ovary.
Measuring Oral Proficiency through Paired‐Task Performance by CSÉPES, ILDIKÓ

A review of the book "Measuring Oral Proficiency Through Paired-Task Performance," by Ildiko Csepes is presented.
Structure and Nucleotide Sequences of the Human Cholesterol 7α-Hydroxylase Gene ( CYP7 )

The human cholesterol 7[alpha]-hydroxylase gene (CYP7) spans about 11 kb of the genome and contains six exons and five introns. Nucleotide sequences of a 5[prime]-upstream region to exon III (5535 bp), a 5[prime]-upstream EcoRI fragment (2575 bp), and an EcoRI fragment covering intron V to exon VI (2319 bp) have been determined. A comparison of the sequences with those reported previously unveiled numerous sequencing discrepancies that are apparently due to sequencing errors. There are only one confirmed and one possible genetic polymorphism in the promoter of this highly conserved human gene. The proximal promoter contained many consensus recognition sequences for liver-enriched transcription factors and steroid hormone receptors that may play important roles in regulation of the CYP7 gene transcription by bile acids, cholesterol, and hormones. 12 refs., 2 figs.
A cross validated bayesian retrieval algorithm for nonlinear remote sensing experiments

Abstract A fully automated retrieval algorithm for estimating nonlinearly sensed functions is presented. This algorithm combines a simple Gauss-Newton iteration with an extended form of Generalized Cross Validation. The performance of the algorithm is illustrated in the context of a remote sensing problem arising in satellite meteorology.
Build Airport Capacity or Manage Flight Demand? How Regional Planners Can Lead American Aviation Into a New Frontier of Demand Management

Problem, research strategy, and findings: To address air traffic congestion, airports can manage flight demand or expand capacity; the Federal Aviation Administration (FAA) requires an environmental impact statement (EIS) to evaluate feasible alternatives to capacity expansion. The FAA also funds regional planning agencies to conduct optional regional aviation systems plans (RASPs). We study the extent to which airports investigate demand management in lieu of increasing capacity and if RASPs play a role in doing so. Of the 17 EISs for major airport capacity expansions between 2000 and 2013, only Boston (BOS), as influenced by the local RASP, fully assessed demand management. We find three barriers to airports evaluating demand management in their EISs: narrow project objectives, uncertainty over the FAA's stand on demand management, and economic development concerns. RASPs can help surmount these barriers because they are not constrained by the EIS's narrow objectives and can comprehensively evaluate dem...
A Phase II Trial of Gemcitabine Plus Capecitabine for Metastatic Renal Cell Cancer Previously Treated With Immunotherapy and Targeted Agents

Purpose: We assessed the clinical activity and safety of gemcitabine plus capecitabine in patients with metastatic renal cell cancer previously treated with immunotherapy.Materials and Methods: In this phase II trial patients received 1,000 mg/m2 gemcitabine intravenously on days 1, 8 and 15, plus 830 mg/m2 capecitabine orally twice daily on days 1 to 21 of 28-day cycles. The primary end point was progression-free survival time. Secondary end points included overall survival time, objective response rate and toxicity.Results: Of 84 patients enrolled 83 were evaluable for response and toxicity. A total of 65 patients had intermediate or poor risk prognosis. Median progression-free survival and overall survival were 4.6 (95% CI 3.7–7.3) and 17.9 months (95% CI 13.2–23.6), respectively. There were 6 partial responses and 1 complete response (objective response rate 8.4% [95% CI 3.5–16.6]). Two patients remain in unmaintained remission close to 3 years from the initiation of gemcitabine plus capecitabine trea...
Temporal expression and activation of matrix metalloproteinases-2, -9, and membrane type 1-matrix metalloproteinase following acute hindlimb ischemia.

Objective. Matrix metalloproteinase (MMP) activity is essential for remodeling of ischemic tissue. The murine hindlimb ischemia model exhibits tissue remodeling including revascularization in part due to angiogenesis. MMP-2 and -9 are type IV collagenases necessary for basement membrane degradation as a part of extracellular matrix remodeling and angiogenesis. Polymorphonuclear leukocytes (PMNs) contain MMP-9, and in the presence of membrane type 1 (MT1)-MMP, are able to activate proMMP-2 in vitro. Activation of MMP-2 and -9 may be essential in ischemic limbs both for tissue remodeling and revascularization via angiogenesis. We hypothesized that MMP-2 and -9 would be activated following acute hindlimb ischemia (HI), and this activation would be temporally related to PMN infiltration. Design of study. HI was achieved by unilateral femoral artery ligation in 20 FVB/N mice. Five mice underwent sham operation without hindlimb ischemia. Gastrocnemius muscle was harvested from both hindlimbs at 1, 3, 14, and 30 days following ligation and assayed for MMP-2, -9 (gelatin zymography), and MT1-MMP (Western blotting). MMP-2 and -9 expression and activation were analyzed by gelatin zymography and quantified by densitometry with NIH Image Analysis software. Neutrophils per high power field were counted. The results were expressed as a ratio of ischemic to nonischemic limbs and compared at each time point using ANOVA. Results. Zymographic analysis revealed a 212% increase in active MMP-2 3 days postligation (P < .05). Active MMP-9 reached its maximum level (800% over baseline) on postoperative day 3 and continued to be elevated on day 14 (737% over baseline) (P < .05). The increase in active MMP-2 and -9 levels paralleled PMN infiltration that also peaked 3 days postligation (1184% over baseline) (P < .05). PMN count, MMP-2, and -9 all returned to baseline levels by postoperative Day 30. MT1-MMP was present in tissue samples from all time points as confirmed by Western blot. Conclusions. Limb ischemia causes an early activation of MMP-2 and -9 in temporal relation to PMN infiltration. HI may prime PMNs, leading to their sequestration in ischemic tissue. Primed PMNs, along with constitutively expressed MT1-MMP, may activate MMPs-2 and -9 and enable tissue remodeling essential for limb revascularization and angiogenesis.
A New Approach for Blind Separation of Convolutive Mixtures

An algorithm for blind source separation (BSS) of convolutive mixtures is discussed here. Separation of signals is performed in two stages. The first stage involves the application of an independent component analysis (ICA) algorithm and in the second stage shrinkage functions are applied to a set of wavelet coefficients. The ICA utilizes maximization of entropy to update the network weights and feedback is used within the network architecture. The ICA network alone can achieve acceptable levels of separation of artificially convolved sources. However, separation quality deteriorates for real-world convolutive mixtures. Hence, the separated signals can have cross-talk components. This work deals with the cross-talk problem by applying a novel postprocessing technique. The signals separated by the ICA network are passed through a post-processor, which has a set of shrinkage functions. The algorithm reduces the cross-talk components significantly as compared to using only the ICA algorithm.
Upregulation of thrombospondin-1 and angiogenesis in an aggressive human pancreatic cancer cell line selected for high metastasis

Pancreatic cancer remains a leading cause of death despite its relatively low incidence. As in many other solid tumors, angiogenesis is critical to the growth and metastasis of this cancer. Through serial in vivo passages in mice, we have developed a highly aggressive variant of human pancreatic cancer cell line XPA-1 which shows more rapid primary tumor growth, faster time to metastasis, and more rapid lethality than the parental cell line. The high-metastatic variant developed a much denser tumor vasculature early during growth within the pancreas. Interestingly, examination of the in vitro growth of this aggressive variant yielded no significant difference from the parental cell line. Real-time PCR evaluation of genes involved in angiogenesis revealed a 24-fold increase in Thrombospondin-1 expression in cells derived from the high-metastatic variant when compared with the parental cell line. These findings provide direct evidence that elevated capability for angiogenesis, mediated by specific changes in gene expression, can lead to a large increase in cancer aggressiveness and resulting metastasis. These findings have important implications for the treatment of metastatic disease.
Spatio-temporal pattern formation during CO oxidation on Pt(100) at low and intermediate pressures: A comparative study.

Experimental studies of CO oxidation on Pt(100) over two different ranges of reactant pressures will be reviewed. Using photoemission electron microscopy (PEEM), spatio-temporal pattern formation was observed at temperatures between 420 and 540 K in the 10−5 mbar pressure range. In an attempt to bridge the “pressure-gap,” ellipsomicroscopy for surface imaging was used to follow pattern formation at temperatures around 600 K in the 10−2 mbar pressure range. The features of the nonlinear phenomena, observed in these two different pressure regimes, are markedly different. This is shown by comparison of various qualitative and quantitative features of spatio-temporal pattern formation as well as the dynamics of the macroscopic reaction rate. Subsurface oxygen is proposed as a tentative alternative to the surface phase transition for oscillations in the reaction rate at higher temperatures and intermediate pressures.
Dearth by a Thousand Cuts?: Accounting for Gender Differences in Top-Ranked Publication Rates in Social Psychology

Publication in the Journal of Personality and Social Psychology, a flagship indicator of scientific prestige, shows dramatic gender disparities. A bibliometric analysis included yoked-control authors matched for Ph.D. prestige and cohort. Though women publish less, at slower annual rates, they are more cited in handbooks and textbooks per JPSP-article-published. No gender differences emerged on variables reflecting differential qualifications. Many factors explain gender discrepancy in productivity. Among top publishers, per-year rate and first authorship especially differ by gender; rate uniquely predicts top-male productivity, whereas career-length uniquely predicts top-female productivity. Among men, across top-publishers and controls, productivity correlates uniquely with editorial negotiating and being married. For women, no personal variables predict productivity. A separate inquiry shows tiny gender differences in acceptance rates per JPSP article submitted; discrimination would be a small-but-plausible contributor, absent independent indicators of manuscript quality. Recent productivity rates mirror earlier gender disparities, suggesting gender gaps will continue.
Dam- and OxyR-Dependent Phase Variation of agn43: Essential Elements and Evidence for a New Role of DNA Methylation

Phase variation of the outer membrane protein Ag43 in E. coli requires deoxyadenosine methylase (Dam) and OxyR. Previously, it was shown that OxyR is required for repression of the Ag43-encoding gene, agn43, and that Dam-dependent methylation of three GATC target sequences in the regulatory region abrogates OxyR binding. Here we report further characterization of agn43 transcription and its regulation. Transcription was initiated from a σ70-dependent promoter at the G residue of the upstream GATC sequence. Template DNA and RNA polymerase were sufficient to obtain transcription in vitro, but DNA methylation enhanced the level of transcription. Analyses of transcription in vivo of agn′-lacZ with mutated Dam target sequences support this conclusion. Since methylation also abrogates OxyR binding, this indicates that methylation plays a dual role in facilitating agn43 transcription. In vitro transcription from an unmethylated template was repressed by OxyR(C199S), which resembles the reduced form of OxyR. Consistent with this and the role of Dam in OxyR binding, OxyR(C199S) protected from DNase I digestion the agn43 regulatory region from −16 to +42, which includes the three GATC sequences. Deletion analyses of the regulatory region showed that a 101-nucleotide region of the agn43 regulatory region containing the promoter and this OxyR binding region was sufficient for Dam- and OxyR-dependent phase variation
Phonology and geographic song discrimination in song sparrows

We investigated whether song sparrows discriminate foreign from local songs using specific phonologic markers, a mechanism of geographic discrimination previously described for some other songbirds. Song sparrows from Linesville, Pennsylvania (PA) respond more strongly to local songs than to songs from Millbrook, New York (NY). We identify 61 note categories in PA and NY songs, of which 13 are unique to PA, 17 are unique to NY, and 31 are shared. The most common note category in PA song, buzz BO5’, is present in 89% of PA songs and only in 8% of NY songs; this difference in percentage representation is the largest we found for any note category. Substituting this potential PA marker into NY songs, however, did not make those songs more salient to PA sparrows; instead, PA males tested with territorial playback responded significantly less aggressively to NY/PA hybrid songs than to NY songs. A series of control experiments showed that song sparrows do not detect substitution of PA notes into PA songs or of NY notes into NY songs. The results weigh against the hypothesis that geographic discrimination in song sparrows is accomplished simply by recognition of a small number of phonologic markers.
Reply to "Comments on 'Discrete Frequency-Coding Waveform Design for Netted Radar Systems'"

For original paper see H. Deng, ibid., vol.11, no.2, p.179-182, (2004). This paper presents reply to "comments on 'discrete frequency-coding waveform design for netted radar systems'".
Silicon deformable mirrors and CMOS-based wavefront sensors

Inexpensive wavefront sensors and deformable mirrors are essential for addressing potential commercial applications for adaptive optics like laser beam control and ophthalmology. Silicon micromachined deformable mirrors offer the potential for low cost and high actuator density, but there are some problems with the architectures currently available like low mirror quality and high actuator crosstalk. Shack-Hartmann wavefront sensors are still based on traditional charge coupled device (CCD) arrays making them very expensive at high frame rates. To address the need for low cost deformable mirrors, we have implemented a new architecture of silicon deformable mirror designed to be low cost, have low actuator crosstalk, and still maintain good mirror quality. Furthermore, we built and tested a CMOS Shack-Hartmann wavefront sensor to address the needs of the adaptive optics community for high speed wavefront sensing.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Role-based access control in DCOM

The explosive growth of the Web, the increasing popularity of PCs and the advances in high-speed network access have brought distributed computing into the mainstream. To simplify network programming and to realize component-based software architecture, distributed object models have emerged as standards. One of those models is distributed component object model (DCOM) which is a protocol that enables software components to communicate directly over a network in a reliable, and efficient manner. In this paper, we investigate an aspect of DCOM concerning software architecture and security mechanism. Also, we describe the concept of role-based access control (RBAC) which began with multi-user and multi-application on-line systems pioneered in the 1970s. And we investigate how we can enforce the role-based access control as a security provider within DCOM, specially in access security policy.
HYPOFRACTIONATION FOR PROSTATE CANCER RADIOTHERAPY—WHAT ARE THE ISSUES?

2. It is generally assumed that the mechanistic basis for the different fractionation response of tumors and late-responding normal tissues relates to the larger proportion of cycling cells in tumors. However, prostate tumors contain unusually small fractions of cycling cells (19), so back in 1999, Brenner and Hall (1) and Duchesne and Peters (2) reasoned that prostate tumors might not respond to changes in fractionation in the same way as other cancers. Both papers hypothesized that prostate tumors might respond to changes in fractionation more like a late-responding normal tissue. In mathematical terms, the suggestion was that the / ratio for prostate cancer might be low, comparable to that for late sequelae. If so, much of the rationale for using many fractions, or using low dose rate, would disappear for prostate radiotherapy. 3. A first estimate of / for prostate cancer was made in 1999 (1) by comparing results from external beam radiotherapy (EBRT) with those from brachytherapy (BT). Consistent with the theoretical hypotheses (see above), the estimated value of / was 1.5 Gy (95% confidence interval: 0.8–2.2 Gy), comparable to / values for late-responding normal tissues, and much smaller than those for most tumors. 4. The problem with this estimate (1) of the / value for prostate, and almost all subsequent estimates (3–11, 13– 18) is that they involve comparing or equating EBRT results with BT results. There are many pertinent differences between EBRT and BT (different dose distributions, different relative biological effectiveness, different overall times, different institutions, different PSA distributions, hypoxia), any or all of which could bias the / estimate. Much of the debate has centered around the significance of these biases, and how to take them into account. Despite these problems, there does seem to be consensus among most of the analyses that have taken this approach, that the / value for prostate cancer is indeed quite low, probably in the 1 to 4 Gy range (1, 2, 4–11, 13–16, 18), which is similar to the values for most late-responding tissues. 5. One analysis has also been performed (12) that avoided many, though not all, of the potential biases involved in comparing EBRT and BT. Here, EBRT a 2-fraction high-dose-rate (HDR) BT boost was compared with EBRT a 3-fraction HDR boost, all done with the same technique at the same institution. The resulting estimated / ratio for prostate cancer was 1.2 Gy (95% confidence interval: 0.03–4.1 Gy), again comparable with / values for late-responding normal tissues. 6. If the / value for prostate cancer is indeed similar to that for the surrounding late-responding normal tissue, one could use fewer fractions (i.e., hypofractionate) or HDR and yet, by choosing the right dose, produce
On the Nature of the B4 Banana Phase: Crystal or Not a Crystal?

Bent-core or banana-shaped liquid crystal mesogens are known to form chiral smectic phases from achiral or racemic molecules, representing the first example of conglomerate formation in bulk fluids. The most well studied examples of this behavior occur in the SmCP phases, subphases possessing the B2 chiral layer structure. However, the first description of chirality in the banana phase space was of the B4 phase, whose detailed structure is still under investigation. Indeed, the B4 phase is quite unique, and a consensus regarding the question of whether this phase is crystalline or liquid crystalline has not been reached. Here we describe data showing distinct differences, by NMR, between the SmCP phase and B4 phase of the prototypical banana phase mesogen NOBOW and, based upon an analysis of these data, suggest that the B4 phase is an unusual type of crystalline solid.
Kinetic analyses of the membrane‐bound alkaline phosphatase activity of hymenolepis diminuta (cestoda: Cyclophyllidea) in relation to development of the tapeworm in the definitive host

The specific activities of the alkaline phosphatase (APase), type I phosphodiesterase and 5'-nucleotidase activities associated with the brush-border plasma membrane of the tapeworm, Hymenolepis diminuta, decrease significantly as the tapeworm grows and matures. Kinetic analyses of the APase activity associated with membrane preparations from whole 6-, 12-, and 18-d-old H diminuta, and individual pieces of 18-d-old H diminuta cut into ten pieces of equal length, failed to demonstrate qualitative changes in the APase activity. Therefore, the decreased specific activities are apparently due to changes in the ratios of enzymatically active to enzymatically inactive membrane proteins (ie, quantitative changes in the membrane proteins) which occur as the tapeworm grows.
Competitive Analysis and Market Power of China’s Soybean Import Market

This research conducts a competitive structure analysis of the Chinese soybean import market which leads to the hypothesis that China’s soybean importers may have stronger market power in China’s soybean import market. Then, this research develops and simultaneously estimates a two-country partial equilibrium trade model to test U.S.-China market power of soybean trade. The empirical result supports our hypothesis that Chinese soybean importers have stronger market power relative to U.S. soybean exporters. This Chinese market power can be countered by U.S. and South American companies through developing new and expanding existing markets for soybeans throughout the world and investing in Chinese soybean storage and crushing capacity.
Full decodable code-word sets

This paper considers further how the decodability condition imposes restrictions on a set of code words. A generating function is defined that describes the composition of the code words. The relation between the generating function and a "full" set of code words is found. This relation shows that the sum of arbitrary probabilities associated with the words of a full set must be one. A full set of code words is one to which no code word can be added and still keep the set decodable. It is also shown that a full set is "completable." For a completable set of code words any string of symbols can be made into a sentence by adding a suitable prefix and a suffix.
Animals Prefer Reinforcement that Follows Greater Effort: Justification of Effort or Within-Trial Contrast?

Justification of effort by humans is a form of reducing cognitive dissonance by enhancing the value of rewards when they are more difficult to obtain. Presumably, assigning greater value to rewards provides justification for the greater effort needed to obtain them. We have found such effects in adult humans and children with a highly controlled laboratory task. More importantly, under various conditions we have found similar effects in pigeons, animals not typically thought to need to justify their behavior to themselves or others. To account for these results, we have proposed a mechanism based on within-trial contrast between the end of the effort and the reinforcement (or the signal for reinforcement) that follows. This model predicts that any relatively aversive event can serve to enhance the value of the reward that follows it, simply through the contrast between those two events. In support of this general model, we have found this effect in pigeons when the prior event consists of: (a) more rather than less effort (pecking), (b) a long rather than a short delay, and (c) the absence of food rather than food. We also show that within-trial contrast can occur in the absence of relative delay reduction theory. Contrast of this kind may also play a role in other social psychological phenomena that have been interpreted in terms of cognitive dissonance.
Plasmodium-host interactions directly influence the threshold of memory CD8 T cells required for protective immunity.

Plasmodium infections are responsible for millions of cases of malaria and ∼1 million deaths annually. Recently, we showed that sterile protection (95%) in BALB/c mice required Plasmodium berghei circumsporozoite protein (CS252–260)-specific memory CD8 T cells exceeding a threshold of 1% of all PBLs. Importantly, it is not known if Plasmodium species affect the threshold of CS-specific memory CD8 T cells required for protection. Furthermore, C57BL/6 mice immunized with radiation-attenuated parasites are more difficult to protect against Plasmodium sporozoite challenge than similarly immunized BALB/c mice; however, it is not known whether this is the result of different CD8 T cell specificity, functional attributes of CD8 T cells, or mouse strain-specific factors expressed in nonhematopoietic cells. In this article, we show that more CS-specific memory CD8 T cells are required for protection against P. yoelii sporozoite challenge than for protection against P. berghei sporozoite challenge. Furthermore, P. berghei CS252-specific CD8 T cells exhibit reduced protection against P. berghei sporozoite challenge in the context of C57BL/6 and C57BL/10 non-MHC-linked genes in CB6F1 and B10.D2 mice, respectively. Generation and immunization of reciprocal chimeric mice between BALB/c and B10.D2 strains revealed that B10 background factors expressed by nonhematopoietic cells increased the threshold required for protection through a CD8 T cell-extrinsic mechanism. Finally, reduced CS-specific memory CD8 T cell protection in P. yoelii-infected BALB/c or P. berghei-infected B10.D2 mice correlated with increased rates of Plasmodium amplification in the liver. Thus, both Plasmodium species and strain-specific background genes in nonhematopoietic cells determine the threshold of memory CD8 T cells required for protection.
Giant and Ultragiant Aerosol Particle Variability over the Eastern Great Lakes Region

Abstract Numerous studies have indicated the potential for giant and ultragiant aerosol particles to expedite the warm-rain process as a result of their extreme sizes. The central question regarding their importance is, Are they present in large enough numbers to influence the microphysics of the clouds significantly? Thus, quantification of these particles and their variability is paramount. New observations collected during the second Alliance Icing Research Study (AIRS II) are presented as evidence of the presence and variability of giant and ultragiant aerosol particles over a continental region—in this case, within the eastern Great Lakes region and parts of the midwestern United States and Canada during one month in winter 2003. Sources and factors contributing to the amount of these particles observed in the lower atmosphere were difficult to identify separately; future studies incorporating high-resolution weather modeling are likely needed.
COX-2 inhibitors. Are they nonsteroidal anti-inflammatory drugs with a better safety profile?

In the treatment of arthritis, NSAIDs are some of the most commonly used drugs, although the prescription of such drugs has been questioned due to their inherent risks for gastrointestinal compromise, platelet effects, and the potential for renal toxicity with long-term use. With the availability of celecoxib and rofecoxib, 2 cyclooxygenase (COX-2) inhibitors (or COX-1 sparing agents) as new forms of NSAIDs, these issues have become magnified not only in the context of risk-to-benefit ratios but also in terms of pharmacoeconomics because they have been proven to be equally efficacious as the nonselective NSAIDs, with an improved safety profile particularly within the gastrointestinal tract, but at a significantly increased cost.
The U.N. Watercourse Convention and Technological Innovation

This paper was prepared for the UNESCO "UN Watercourse Convention Global Initiative" Symposium held at the University of Dundee in April 2012. This paper evaluates how the United Nations Convention on the Non-Navigational Uses of International Watercourses (the “Watercourse Convention”) governs new and developing technologies that can both aggravate and mitigate conflict arising in international river basins. Using the examples of desalination and deep fossil aquifer drilling technologies, this paper also proposes an interpretation of the principles of the Watercourse Convention intended to better facilitate responsible development and implementation of new or developing technologies in international watercourses.
Implementation of integrated stepped care for unhealthy alcohol use in HIV clinics

Effective counseling and pharmacotherapy for unhealthy alcohol use are rarely provided in HIV treatment settings to patients. Our goal was to describe factors influencing implementation of a stepped care model to address unhealthy alcohol use in HIV clinics from the perspectives of social workers, psychologists and addiction psychiatrists. We conducted two focus groups with Social Workers (n = 4), Psychologists (n = 2), and Addiction Psychiatrists (n = 4) involved in an ongoing randomized controlled trial evaluating the effectiveness of integrated stepped care for unhealthy alcohol use in HIV-infected patients at five Veterans Health Administration (VA) HIV clinics. Data collection and analyses were guided by the Consolidated Framework for Implementation Research (CFIR) domains, with a focus on the three domains which we considered to be most relevant: intervention characteristics (i.e. motivational interviewing, pharmacotherapy), the inner setting (i.e. HIV clinics), and characteristics of individuals (i.e. the providers). A multidisciplinary team used directed content analysis to identify major themes. From the providers’ perspective, the major implementation themes that emerged by CFIR domain included: (1) Intervention characteristics: providers valued tools and processes for facilitating patient motivation for treatment of unhealthy alcohol use given their perceived lack of motivation, but expressed a desire for greater flexibility; (2) Inner setting: treating unhealthy alcohol use in HIV clinics was perceived by providers to be consistent with VA priorities; and (3) Characteristics of individuals: there was high self-efficacy to conduct the intervention, an expressed need for more consistent utilization to maintain skills, and consideration of alternative models for delivering the components of the intervention. Use of the CFIR framework reveals that implementation of integrated stepped care for unhealthy alcohol use in HIV clinics is facilitated by tools to help providers enhance patient motivation or address unhealthy alcohol use among patients perceived to be unmotivated. Implementation may be facilitated by its consistency with organizational values and existing models of care and attention to optimizing provider self-efficacy and roles (i.e. approaches to treatment integration).
Descending propriospinal neurons mediate restoration of locomotor function following spinal cord injury

In the lamprey following spinal lesion-mediated interruption of long axonal projections of reticulospinal (RS) neurons, sensory stimulation still elicited relatively normal locomotor muscle burst a...
Process in Genetic Counseling: Considerations for Children and Their Families

The clinical variability seen in a single, inherited genetic condition is equally matched by the variability of the individual, as well as the family’s response to it (O’Daniel & McConkie-Rosell, 2006). As the practice of medicine evolves beyond single gene and chromosomal disorders to include genomics, this variability is magnified many times over. Medical genomics involves the incorporation of risk associations, which are most often based on the analysis of combinations of multiple genetic variants. Patients, thus, may receive risk estimates (rather than genetic diagnoses) for a range of health conditions and states including adverse drug response and cancer recurrence. Although the magnitude and heritability of risk varies significantly between medical genetics and genomics, the basic tenets of genetic counseling can still apply.
Effect of Intensive Versus Standard Clinic-Based Hypertension Management on Ambulatory Blood Pressure: Results From the SPRINT (Systolic Blood Pressure Intervention Trial) Ambulatory Blood Pressure Study.

The effect of clinic-based intensive hypertension treatment on ambulatory blood pressure (BP) is unknown. The goal of the SPRINT (Systolic Blood Pressure Intervention Trial) ambulatory BP ancillary...
Respiratory Pigments: Structure and Function

Publisher Summary This chapter discusses the structure and function of respiratory pigments. Oxygen is the final electron acceptor involved in aerobic respiration. In mollusks, as in many other organisms, oxygen-carrying proteins that facilitate the transfer of oxygen from the environment to cytochrome c oxidase, a transmembrane protein of the inner mitochondrial membrane, have evolved. The diffusion of oxygen from the environment to cytochrome c oxidase in the mitochondrion is generally sufficient in organisms where the diffusion pathway is short. However, hemoglobins have been found in a number of protozoans, turbellarian and trematode platyhelminthes, nemerteans, and nematodes. In the course of evolution, three classes of respiratory pigments have evolved: the globins (myoglobins and hemoglobins), the hemerythrins, and the hemocyanins. There are numerous mollusks for which data have not yet been collected. In general, the oxygen-binding site has an oxygen affinity that is determined by its electronic environment, dictated by the protein moiety in which it is contained. In the simplest case, where a single polypeptide chain contains a single binding site for oxygen, the reversible binding of oxygen by the oxygen carrier can be described by a single equilibrium constant.