bluuebunny/crossref_metadata_2025 huggingface dataset:
WE‐E‐AUD‐04: Radiation Characteristics and Hypo‐Fractionation Dose Response for the DVS Implantable MOSFET Dosimeter
Authors: Beyer GP , Pursley J , Mann G , Espenhahn E , Fraisse C , Godfrey D , Oldham M
Published: July 2007

Purpose: Evaluation of the radiation characteristics and performance of the DVS® implantable MOSFET dosimeter for typical and hypo‐fractionated protocols. Method and Materials: The commercially available DVS is calibrated for use in the range of 150–250 cGy per fraction up to 80 Gy. The dosimeter was evaluated to determine its radiation characteristics, including response to energy, angular dependence, temperature, and dose shadowing. Dosimeter performance was also validated in a phantom simulating different radiation treatment conditions. A high dose calibrated dosimeter for use with hypo‐fractionated protocols is introduced. Phantom measurements were performed to validate this dosimeter in the dose per fraction range of 400–1200 cGy. All phantom data was validated using a NIST‐traceable calibrated ion chamber. Results: The DVS was found to have a very small energy dependency (⩽1.5%) in the ‐18 MV range. With kV onboard imaging, an over‐response was only measurable for doses from kV‐CBCT. The radial angular dependence was found to be within 1.4% and the maximum angular dependence (6%) was obtained for beams traveling through the coil and electronics. A dosimeter implanted in close parallel alignment with the sagittal body axis would minimize this effect. Since the DVS is calibrated at 37°C (for use at body temperature), measurements performed at room temperature require a correction factor of approximately 1.033. Phantom measurements (23°C, 37°C) resulted in values well within the specified accuracy of 5%. The dosimeter calibrated for use in hypo‐fractionation applications resulted in an average variability of −0.3% (σ=2.2%) from predicted dose in the range of 400–1200cGy per fraction. Conclusions: This data suggests that DVS can be used, together with current delivery and planning techniques, to optimize radiation treatment by measuring the dose delivered in the treatment area. Testing shows the potential to use the high‐dose calibrated dosimeter with hypo‐fractionated radiation treatments.

Research sponsored by Sicel Technologies, Inc.
WE‐E‐BRA‐01: Effects of Major Component Replacement in a Tomotherapy HiART System On Radiotherapy QA Measurements
Authors: Sen A , West M , Movahed A
Published: July 2007

Purpose: On our Tomotherapy system several major components have been changed frequently in one year. This study investigates the possible relationship of component failure with treatment load, and the related QA issues following component replacement. Method and Materials: Tomotherapy HiART is a complex radiotherapy equipment where a linac, magnetron and all the components are mounted on a rotating slip ring gantry. It operates at a high dose rate compared to conventional linacs. The major components — target, magnetron and the linac have been changed five, three and two times, respectively during one year of use. Following major component replacement, the PDD, profiles, output and energy have been measured with ion chambers, water scanner and films to bring the system to agreement with commissioning condition. Results: The output and the energy constancy variation over the entire year were within +/− 6 % and +/− 3.5%, respectively with no definite predictor of an imminent component failure. The dose rate varied between −10% and +5% during the same period. Annual average of daily treatments was 24 with a maximum daily average of 37.3 treatments in a month. Target change interval ranged between 12 and 80 days. The mean time between major component failures was 35.6 days. Conclusion: Analysis of the data could not identify any pattern of component failure. Examination of targets indicated holes, flakiness and uneven erosion in some targets indicating unknown changes in the beam. Magnetron changes were primarily due to arcing. Target and linac change involved more alignment, beam characteristics and QA measurements and longer downtime. The hole in the target poses a beam spectrum different from the commissioned beam. Target or the linac replacement caused more downtime and QA measurements than the magnetron change.
WE‐E‐BRA‐06: Imaging Linear Accelerator Startup Using a High‐Speed Scintillation Based Electronic Portal Imaging Device (Hi‐EPID)
Authors: Ranade M , Lynch B , Li J , Kim S , Dempsey J
Published: July 2007

Purpose: Using the high‐speed scintillation based electronic portal imaging device (Hi‐EPID), to analyze the characteristics of the fluence delivered from a commercial clinical linear accelerator (Synergy® S, Elekta). To study the fluence output at short time scales. Method and Materials: The Hi‐EPID consists of a high speed digital camera coupled with a fast terbium‐doped gadolinium‐oxy‐sulfide (Gd2O2S:Tb) scintillator. The camera can record every single radiation pulse out of the accelerator, at up to 500 fps. Both open field and multileaf collimator (MLC) based intensity modulated radiation therapy (IMRT) fields were evaluated. The startup time of linac delivery was recorded. Results: Fluence delivery irregularities were observed with the Hi‐EPID device, within 250 ms. For the open field delivery, the fluence increased with time until it reached a plateau, in approximately 100 to 250 ms, and then remained constant. However, in the case of a six segment IMRT field delivery, the fluence variation differed between segments. For some segments, the fluence increased in the beginning and then reached a plateau. For others, the fluence rose and fell sharply, followed by a slower rise to the plateau. The rapid fluence variation before a plateau was as high as 60% of the maximum. A field size dependence of fluence was observed. An analysis of field shapes showed no unplanned motion of MLC was during step and shoot delivery, as has been reported for other clinical linac. Conclusion: The Hi‐EPID is capable of imaging the fluence out of a linear accelerator with high temporal resolution. The startup characteristics of the accelerator can be studied. For short time IMRT segments, fluence and dose rate varied over a significant portion of the segment. As the dose rate fluctuates during startup, its effect on IMRT delivery can be studied.

This work was supported by NCI grant R01‐CA‐100636.
WE‐E‐BRA‐07: Experimental Determination of the LiF:Mg,Ti TLD Energy Response Correction Factor for 125I Brachytherapy Sources
Authors: Rasmussen B , Davis S , Micka J , DeWerd L
Published: July 2007

Purpose: To further explore the energy response correction factor for LiF:Mg,Ti thermoluminescent dosimeters for use in experiments with low dose rate brachytherapy sources. Method and Materials: Two distinct experiments were performed to determine the value of the energy response correction factor, E(r), as defined in TG‐43U1, for seeds. The University of Wisconsin Variable Aperture Free Air Chamber was used to determine the air kerma strengths of Best Medical 2301 seeds. A 3×3 array of TLD‐100 chips sealed in a thin plastic bag was attached to the center of the aperture using Kapton tape. was used to irradiate a set of comparison TLDs to a dose to water equivalent to the dose to water given by . Monte Carlo simulations were used in both cases to calculate the dose to water from the measured air kerma. The two experiments had different annealing techniques: one using a standard anneal of one hour at 400°C followed by 24 hours at 80°C, and the other using a standard anneal at the beginning of the sorting process and then only the 80°C anneal between cycles. Results: E(r) was determined to be 1.514 ± 0.019 using the 80°C technique and 1.549 ± 0.025 using the standard technique. These values are significantly higher than the currently applied value of 1.41, but not unexpected. TG‐43U1 noted that the work of Davis et al. also observed an anomalous over‐response relative to theoretical predictions. It is speculated that the differences between these two experimental values may be the result of the annealing techniques and TL readout characteristics, which will be further investigated. Conclusion: It appears that LiF:Mg,Ti TLDs are indeed intrinsically non‐linear in their response to low energy photons. The solid state processes that cause this effect are not taken into account by Monte Carlo.
TH‐C‐AUD‐07: Variations in Scanned Beam Proton Therapy Doses Due to Random Magnetic Beam Steering Errors
Authors: Peterson S , Polf J , Frank S , Bues M , Smith A
Published: July 2007

Purpose: To study perturbations to delivered dose due to steering uncertainties of magnetically scanned proton beams. Understanding the effect of these perturbations on the delivered dose will help in determination of appropriate treatment structure volume (TS) expansions to ensure adequate coverage. Method and Materials: Monte Carlo simulations were performed using a model of a clinical scanned‐beam treatment nozzle to calculate the delivered dose spots from magnetically scanned proton pencil beams. Using a simple dose calculation program, the simulated dose spots were used to create a treatment plan to deliver a uniform 75 Gy dose to a TS within a water phantom. To determine effects of steering uncertainties, small random magnetic field perturbations (ΔB⩽±0.1%) were added to the steering parameters used to deliver a uniform TS dose. Variations in the dose delivered to the TS and an adjacent critical structure (CS) due to magnetic steering uncertainties were determined. This included determination of dose hot and cold spots in the TS, and changes to the dose volume histogram (DVH) of the TS and CS. Results: The TS volume receiving 95% of the prescribed dose decreased by as much as 7% and the maximum TS dose increased by as much as 13% due to random magnetic steering uncertainties. For the CS, very little change was observed in the DVH with the maximum dose increasing by up to 10%. The maximum possible dose hot and cold spots created by deliberately moving adjacent spots in the TS were calculated to be 187% and 52% of the prescription dose, respectively. Conclusion: For the expected range of ΔB values within the beam‐scanning steering magnets, significant variations in the dose delivered were observed. We conclude that magnetic steering uncertainties should be considered when determining appropriate expansions during treatment planning.
TH‐C‐M100E‐03: A New Generation of Electronic Portal Imaging Devices (EPID) Using Thin‐Film CdTe for Radiation Oncology Applications
Authors: Shvydka D , Parsai E , Kang J , Pearson D
Published: July 2007

Purpose: The commercially available EPIDs today commonly manufactured from amorphous‐Silicone (a‐Si) materials display numerous problems in image contrast & resolution. These are related to poor radiation hardness and low Z which is detrimental to their detecting capabilities. The CdTe‐based thin film devices with superior radiation hardness and much higher Z (∼50) have not yet found many applications in medical physics. Here we report first promising results on polycrystalline thin film CdTe‐based prototype EPID. Method and Materials: The proposed design utilizes a layer of high atomic number and density functioning as a converter transforming high energy X‐rays into the Compton electrons impeding onto CdTe detector operating in pulse mode. Such a converter can replace the standard scintillators used with a‐Si devices. We conducted Monte Carlo simulations testing the proposed structure and verified them with measurements using a prototype thin film CdTe cells. Our modeling was amplified with a semi‐empirical algorithm accounting for the processes of device degradation, simultaneously applied to the a‐Si devices for comparative study. Results: We found that a layer of Pb less than 3 mm thick in combination with low‐Z material such as polystyrene, used for filtering out low‐energy scatter, is suitable for the converter. Detector output voltage in the range of the tenths of Volt for the typical radiation therapy dose rates allowed for a possibility of using the device without biasing. We have carried out verifying experiments with polycrystalline CdTe based cells: good agreement with our MC simulations was obtained. Conclusion: CdTe based thin film detectors have a high potential to become the next generation EPID's. They feature: small thickness <10 μm; efficient collection; exceptional radiation hardness; inexpensive deposition technology; sensitivity to low intensity radiation; excellent room temperature characteristics without biasing; small integration time < 500 ns.
TH‐D‐M100J‐09: Activity Recovery From Dual Radiotracer PET Scans
Authors: Vanderhoek M , Barbee D , Jeraj R
Published: July 2007

Purpose: Comprehensive assessment of tumor biological substructure requires multiple PET radiotracers resulting in time‐consuming imaging procedures. Ideally, multiple PET scans should be performed during one “imaging session,” resulting in the presence of multiple radiotracers during the later scans. We aim to develop a methodology to recover the activities of two mixed radionuclides present during a PET scan. Method and Materials: A heterogeneous tumor phantom composed of empty acrylic spheres mounted inside a cylindrical “background region” filled with low‐activity solution was scanned for 10‐minutes. Then, high‐activity solution was injected into the spheres while low‐activity solution was mixed into the background region and a 600‐minute dynamic PET scan was acquired. Images containing one radionuclide were subtracted from dual‐radionuclide images, yielding “recovered images” of each radionuclide. Recovered images were compared with single radionuclide reference images.

Subsequently, canine subjects with nasopharyngeal tumors were injected with ‐ATSM (hypoxia radiotracer) and scanned 24 hours later, followed immediately by 18FLT injection (cellular proliferation radiotracer) and another scan. Images from ‐ATSM canine scans were subtracted from dual‐radiotracer images. Results: Recovered phantom images closely correlated with reference images. image correlation coefficients were consistently higher than 0.96 and increased as “contamination” decayed. image correlation coefficients were higher than 0.95 for background activities greater than 14% of the total background activity. By image subtraction, the biological distribution of 18FLT in the canine nasopharyngeal tumors was recovered from the dual‐radiotracer images. Conclusions: Radionuclide activities can be effectively recovered from PET scans containing two mixed radionuclides. Subtraction of single radiotracer images from dual‐radiotracer images is a reliable method of activity recovery, provided the pharmacokinetics of one radiotracer is stable during dual‐radiotracer image acquisition. Implications are positive for sequential imaging of different physiological functions using multiple radiotracers during one “multiple PET scan” imaging session.
Brillouin Scattering Studies of Liquid-Glass Transition in n-Propanol as a Function of Temperature and Pressure
Authors: Takagi Yasunari , Yano Toru , Ahart Muhtar , Kojima Seiji
Published: July 2007

The liquid-glass transition in n-propanol is investigated in detail by measuring temperature and pressure dependences of the Brillouin scattering spectra. The experimental data were analyzed using a spectral function based on the theory of the viscoelastic theory and the Vinet equation of state. These yielded the temperature and the pressure dependences of the limiting zero and infinite frequency sound velocities, and the relaxation time. In comparing these results, we found big difference between isobaric cooling and isothermal pressurizing process. The relaxational phenomena in n-propanol are also discussed.
Identification and Clinical Significance of Mobilized Endothelial Progenitor Cells in Tumor Vasculogenesis of Hepatocellular Carcinoma
Authors: Yu Decai , Sun Xitai , Qiu Yudong , Zhou Jianxing , Wu Yafu , Zhuang Lingyuan , Chen Jun , Ding Yitao
Published: July 2007

Purpose: To investigate the distribution, frequency, and clinical significance of mobilized endothelial progenitor cells (EPC) in hepatocellular carcinoma (HCC).

Experimental Design: In healthy controls and patients with HCC, the frequency of circulating EPCs was determined by colony-forming assays, fluorescence-activated cell sorting, and real-time PCR. One hundred sixty-five–amino acid form of vascular endothelial growth factor and platelet-derived growth factor-BB in plasma and tissue were quantified by ELISA. The distribution and frequency of EPCs were evaluated by immunofluorescence, immunohistochemistry, and real-time PCR in normal liver (n = 8), and tumor tissue (TT), adjacent nonmalignant liver tissue (AT), and tumor-free tissue 5 cm from the tumor edge (TF) from 64 patients with HCC. Clinicopathologic data for these patients were evaluated.

Results: Compared with values for healthy controls, colony-forming unit scores were higher in the peripheral blood of patients with HCC. Plasma 165-amino acid form of vascular endothelial growth factor and platelet-derived growth factor-BB correlated with the expression level of the AC133 gene, which was also higher in the peripheral blood of patients with HCC. Immunohistochemical analysis showed that EPCs were incorporated into the microvessels in cirrhotic and tumor tissue. Compared with normal liver (9.00), increased AC133+ microvessel density (microvessels/0.74 mm2) was found in TT (53.56), AT (84.76), and TF (48.33). The levels of AC133 gene expression and AC133-microvessel density in AT, which were the highest among four groups, correlated with clinicopathologic variables (the absence of tumor capsule, venous invasion, proliferating cell nuclear antigen intensity, and early recurrence).

Conclusions: Mobilized EPCs participate in tumor vasculogenesis of HCC. AC133 gene or antigen in peripheral blood and liver tissue could be used as a biomarker for predicting the progression of HCC.
Immune Signatures of Murine and Human Cancers Reveal Unique Mechanisms of Tumor Escape and New Targets for Cancer Immunotherapy
Authors: Sadun Rebecca E. , Sachsman Suzanne M. , Chen Xiaoying , Christenson Kamilee W. , Morris William Z. , Hu Peisheng , Epstein Alan L.
Published: July 2007

Purpose: Despite lymphocyte infiltration of tumors and the activation of tumor-draining lymph nodes, malignant tumors are able to “escape” from both innate and adaptive immune responses. For immunotherapy to be successful, it must reverse these escape mechanisms, which necessitates explicit and tumor-specific elucidation of tumor escape strategies.

Research Design: To identify relevant escape mechanisms in murine tumors and in two corresponding human cancers, real-time reverse transcription-PCR was used to measure a panel of genes associated with T-cell activation and inhibition pathways.

Results: Comparative analysis of the expression levels of these immunomodulatory genes showed astonishing similarities in expression patterns between murine and human breast cancers but profound variability in the expression of immunomodulatory genes in colorectal cancers. For human ductal adenocarcinoma of the breast, down-regulation of dendritic cell maturation marker CD83 and T-cell activation gene CD28 was observed as well as a notable increase in the expression of the immunoinhibitory gene B7-H4. By contrast, colorectal adenocarcinoma cases showed high variability in tumor escape mechanisms, indicating a need to produce immune signatures for individual patients to identify appropriate immunotherapeutic targets.

Conclusions: These results show that certain tumors, such as ductal carcinoma of the breast, show consistent immunologic abnormalities that can be used as targets for immunotherapy. These findings also show the importance and feasibility of determining the immune signatures of patients' tumors to select appropriate immunotherapeutic strategies. Ultimately, these results advocate for the determination of immune signatures as part of the customary repertoire of clinical diagnostics for cancer.
Bevacizumab-Induced Transient Remodeling of the Vasculature in Neuroblastoma Xenografts Results in Improved Delivery and Efficacy of Systemically Administered Chemotherapy
Authors: Dickson Paxton V. , Hamner John B. , Sims Thomas L. , Fraga Charles H. , Ng Catherine Y.C. , Rajasekeran Surender , Hagedorn Nikolaus L. , McCarville M. Beth , Stewart Clinton F. , Davidoff Andrew M.
Published: July 2007

Purpose: Dysfunctional tumor vessels can be a significant barrier to effective cancer therapy. However, increasing evidence suggests that vascular endothelial growth factor (VEGF) inhibition can effect transient “normalization” of the tumor vasculature, thereby improving tumor perfusion and, consequently, delivery of systemic chemotherapy. We sought to examine temporal changes in tumor vascular function in response to the anti-VEGF antibody, bevacizumab.

Experimental Design: Established orthotopic neuroblastoma xenografts treated with bevacizumab were evaluated at serial time points for treatment-associated changes in intratumoral vascular physiology, penetration of systemically administered chemotherapy, and efficacy of combination therapy.

Results: After a single bevacizumab dose, a progressive decrease in tumor microvessel density to <30% of control was observed within 7 days. Assessment of the tumor microenvironment revealed a rapid, sustained decrease in both tumor vessel permeability and tumor interstitial fluid pressure, whereas intratumoral perfusion, as assessed by contrast-enhanced ultrasonography, was improved, although this latter change abated by 1 week. Intratumoral drug delivery mirrored these changes; penetration of chemotherapy was improved by as much as 81% when given 1 to 3 days after bevacizumab, compared with when both drugs were given concomitantly, or 7 days apart. Finally, administering topotecan to tumor-bearing mice 3 days after bevacizumab resulted in greater tumor growth inhibition (36% of control size) than with monotherapy (88% bevacizumab, 54% topotecan) or concomitant administration of the two drugs (44%).

Conclusions: Bevacizumab-mediated VEGF blockade effects alterations in tumor vessel physiology that allow improved delivery and efficacy of chemotherapy, although careful consideration of drug scheduling is required to optimize antitumor activity.
Reduced Likelihood of Metastases in Patients with Microsatellite-Unstable Colorectal Cancer
Authors: Malesci Alberto , Laghi Luigi , Bianchi Paolo , Delconte Gabriele , Randolph Ann , Torri Valter , Carnaghi Carlo , Doci Roberto , Rosati Riccardo , Montorsi Marco , Roncalli Massimo , Gennari Leandro , Santoro Armando
Published: July 2007

Purpose: The outcome of patients with colorectal cancer is more favorable when the tumor exhibits high-frequency microsatellite instability (MSI). Although associated with earlier-stage tumors, MSI has been proposed as an independent predictor of survival. We tested the prognostic value of MSI in a large series of patients diagnosed with colorectal cancer in the last decade.

Experimental Design: The survival of 893 consecutive patients with colorectal cancer characterized by microsatellite status was analyzed. The 89 (10%) patients with MSI cancer were classified according to tumor mismatch repair (MMR) defect, MMR germ-line mutation, hMLH1 and p16 promoter methylation, BRAF and K-ras mutations, and frameshifts of target genes.

Results: The colorectal cancer–specific survival was significantly (P = 0.02) better in patients with MSI cancer than in those with stable tumor (MSS). MSI did not predict a significantly lower risk of cancer-related death if tumor stage was included in the multivariate analysis [hazard ratio, 0.72; 95% confidence interval (95% CI), 0.40-1.29; P = 0.27]. Instead, MSI was strongly associated with a decreased likelihood of lymph node (odds ratio, 0.31; 95% CI, 0.17-0.56; P < 0.001) and distant organ (odds ratio, 0.13; 95% CI, 0.05-0.33; P < 0.001) metastases at diagnosis, independently of tumor pathologic features. Molecular predictors of reduced metastatic risk, and then of more favorable prognosis, included TGFβRII mutation for all MSI tumors, hMSH2 deficiency for hereditary non-polyposis colorectal cancer, and absence of p16 methylation for sporadic hMLH1-deficient cancers.

Conclusions: Tumor MSI is a stage-dependent predictor of survival in patients with colorectal cancer. The decreased likelihood of metastases in patients with MSI cancer is associated with specific genetic and epigenetic changes of the primary tumor.
Temperate Mountain Glacier-Melting Rates for the Period 2001–30: Estimates from Three Coupled GCM Simulations for the Greater Himalayas
Authors: Ren Diandong , Karoly David J. , Leslie Lance M.
Published: July 2007

The temperate glaciers in the greater Himalayas (GH) and the neighboring region contribute to the freshwater supply for almost one-half of the people on earth. Under global warming conditions, the GH glaciers may melt more rapidly than high-latitude glaciers, owing to the coincidence of the accumulation and ablation seasons in summer. Based on a first-order energy balance approach for glacier thermodynamics, the possible imposed additional melting rate was estimated from three climate simulations using the Geophysical Fluid Dynamics Laboratory Global Coupled Climate Model version 2.1 (GFDL-CM2.1), the Model for Interdisciplinary Research on Climate 3.2, high-resolution version (MIROC3.2-hires), and the Met Office’s Third Hadley Centre Coupled Ocean–Atmosphere General Circulation Model (HadCM3). The simulations were carried out under the Special Report on Emissions Scenarios (SRES) A1B scenario. For the 30-yr period of 2001–30, all three CGCMs indicate that the glacial regions most sensitive to regional warming are the Tianshan–Altai Mountains to the north and Hengduan Mountains to the south. A map of potential melting was produced and was used to calculate the glacier-melting speed, yielding an additional spatially averaged glacier depth reduction of approximately 2 m for the 2001–30 period for those areas located below 4000 m. Averaged over the entire GH region, the melting rate is accelerating at about 5 mm yr−2. The general circulation over the GH region was found to have clear multidecadal variability, with the 30-yr period of 2001–30 likely to be wetter than the previous 30-yr period of 1971–2000. Considering the possible trend in precipitation from snow to rain, the actual melting rates of the GH glaciers may even be larger than those obtained in this research.
A Simulation Model of the DOCSIS Protocol
Authors: Martin Jim , Westall James
Published: July 2007

The number of households and businesses using hybrid fiber coaxial cable networks for Internet access is rapidly approaching 40 million in the United States. The cable industry has standardized on a single medium access control (MAC) and physical layer standard, the Data Over Cable Service Interface Specification (DOCSIS). The MAC layer of the emerging IEEE 802.16 broadband wireless access standard is also based upon DOCSIS. Thus, the performance of DOCSIS is now and will remain a critical element in the overall performance of shared medium broadband access networks. Despite this fact, public domain tools that may be used to assess and improve the performance of DOCSIS have been slow to emerge. To address this problem, we have implemented a simulation model of the DOCSIS MAC layer for the ` ns' network simulation tool. Due to the complexity of DOCSIS and because the specifications are purposely incomplete, developing an accurate simulation is quite challenging. In this paper we present analytic and live network evidence that the simulation accurately reflects the behavior of a DOCSIS network under a limited set of workloads.
Using simple and complex growth models to articulate developmental change: Matching theory to method
Authors: Ram Nilam , Grimm Kevin
Published: July 2007

Growth curve modeling has become a mainstay in the study of development. In this article we review some of the flexibility provided by this technique for describing and testing hypotheses about: (1) intraindividual change across multiple occasions of measurement, and (2) interindividual differences in intraindividual change. Through empirical example we demonstrate how linear, quadratic, latent basis, exponential, and multiphase versions of the model can be specified using commonly available SEM/multilevel modeling software and illustrate and discuss how results are obtained and interpreted. Particularly, we underscore the “developmental theory” articulated by each model.
Antibacterial and Laundering Properties of AMS and PHMB as Finishing Agents on Fabric for Health Care Workers' Uniforms
Authors: Chen-Yu Jessie H. , Eberhardt Darlene M. , Kincade Doris H.
Published: July 2007

This study examined whether antibacterial finishes can effectively reduce the presence of bacteria on fabric used for health care workers' uniforms (HCWUs). The specific objectives of this research were (a) to compare the antibacterial property (percentage bacterial reduction) of a 65/35 polyester/cotton blend fabric treated with two commercially available antibacterial agents, AEGIS Microbe Shield (AMS) and polyhexamethylene biguanide (PHMB), before laundering and after 5, 10, and 25 laundering cycles and (b) to determine which agent may be a better choice for HCWU fabrics. The results provided evidence that an antibacterial finish can be an effective way to combat the problem of bacteria contamination. PHMB-treated fabrics are a good candidate for use in reusable HCWUs incurring up to 25 laundering cycles. PHMB-treated specimens had a significantly larger reduction against both Staphylococcus aureus and Klebsiella pneumoniae bacteria before laundering and after 5, 10, and 25 laundering cycles than did AMS-treated specimens and no-treatment specimens.
Child and Parent Predictors of Perceptions of Parent—Child Relationship Quality
Authors: Gerdes Alyson C. , Hoza Betsy , Arnold L. Eugene , Hinshaw Stephen P. , Wells Karen C. , Hechtman Lily , Greenhill Laurence L. , Swanson James M. , Pelham William E. , Wigal Timothy
Published: July 2007

Objective/Method: Predictors of perceptions of parent—child relationship quality were examined for 175 children with ADHD, 119 comparison children, and parents of these children, drawn from the follow-up phase of the Multimodal Treatment Study of Children with ADHD. Results/Conclusion: Children with ADHD perceived their mothers and fathers as more power assertive than comparison children. Children higher on depressive symptomatology also perceived their mothers and fathers as less warm and more power assertive. Mothers perceived themselves as more power assertive and fathers perceived themselves as less warm if they were higher on depressive symptomatology themselves or had children with ADHD or higher levels of depressive symptomatology. Several interactions indicated that the association between child factors and parental perceptions of warmth and power assertion often depended on parental depressive symptomatology. The findings resolve a previous contradiction in the literature regarding the relationship between child depressive symptoms and parental perceptions of parent—child relationship quality. (J. of Att. Dis. 2007;11(1) 37-48)
Characteristic Profiles of Instrumental Activities of Daily Living in Chinese Older Persons with Mild Cognitive Impairment
Authors: Woon Chi Tam Cindy , Chiu Wa Lam Linda , Chiu Helen F.K. , Lui Victor W.C.
Published: July 2007

Increasing evidence suggests that performance of the instrumental activities of daily living (IADL) can be impaired at the mild cognitive impairment (MCI) stage. Our study aimed at investigating the profiles of functional impairment in Chinese subjects with MCI.

Subjects with MCI were categorized into single-domain amnestic MCI (a-MCI) (n = 54) and multiple-domain amnestic MCI (md-MCI) (n = 93) groups. Their functional scores of Disability Assessment of Dementia (DAD) were compared with those of cognitively normal elderly controls (NC) (n = 78) and those with mild Alzheimer's disease (AD) (n = 85).

Subjects with md-MCI had intermediate performance in IADL between the NC and those with mild AD. Subjects with a-MCI had functional scores similar to those of normal controls. Age, education, and global cognitive test scores were not associated with functional scores in MCI subjects.

Our results demonstrated that Chinese older persons with md-MCI had impairment in IADL, as compared to NC and subjects with a-MCI. This finding suggests that assessment of IADL should be incorporated in the clinical evaluation of MCI.
Gender Differences in Impulsivity
Authors: Chapple Constance L. , Johnson Katherine A.
Published: July 2007

Criminological theories have often stressed the importance of impulsivity in the etiology of delinquency. Whether this construct is termed impulsivity, self-control, or low constraint/ negative emotionality, the theoretical importance of impulsivity is clear. What is also clear is that boys and girls differ significantly on impulsivity; however, research is ambiguous on why this occurs. Some researchers suggest that socialization and parenting create different levels of impulsivity, whereas others suggest that cognitive and/or motor deficits early in life may be the source. Using longitudinal National Longitudinal Survey of Youth (NLSY79)–Child data and variables derived from past research on impulsivity, the authors investigate whether biological, structural, and familial predictors of impulsivity differ by gender. Through multiple group path analysis, the authors find that the relationships between discipline and impulsivity and attachment and impulsivity differ significantly by gender. The authors discuss the implications of this finding for the etiology of impulsivity.
Re-creating Through Recreating
Authors: Kluge Mary Ann
Published: July 2007

Although many people are uncertain of what to expect of the aging experience, the ideology of conscious aging (consciousness expansion and personal growth) has merit. This article describes a workshop called The Women We Are Becoming: Re-creating Through Recreating in the Later Years that was designed to challenge established norms and narratives about aging by shifting the focus on aging from decline to development. Transformative learning as a philosophy and experiential learning as a method provided women participants with opportunities to become conscious of their own aging through object lessons presented in outdoor settings.
Insights into the mechanism of FTY720 and compatibility with regulatory T cells for the inhibition of graft-versus-host disease (GVHD)
Authors: Taylor Patricia A. , Ehrhardt Michael J. , Lees Christopher J. , Tolar Jakub , Weigel Brenda J. , Panoskaltsis-Mortari Angela , Serody Jonathan S. , Brinkmann Volker , Blazar Bruce R.
Published: July 2007

The immunomodulator FTY720 (FTY) has been shown to be beneficial in experimental models of organ transplantation and autoimmunity. We show that FTY significantly inhibited but did not prevent graft-versus-host disease (GVHD) in lethally irradiated or nonirradiated allogeneic recipients. Although most studies implicate prevention of lymphocyte egress from lymphoid organs as the primary mechanism of action, our data indicate that FTY effects on the host are more likely to be responsible for GVHD inhibition. FTY reduced splenic CD11c+ cells by 50%, and similarly reduced CD4+ and CD8+ T-cell responder frequencies in the spleen early after transplantation. Imaging of GFP+ effectors indicated that FTY modified donor effector T-cell migration to secondary lymphoid organs, but did not uniformly trap T cells in lymph nodes or prevent early effector migration to GVHD parenchymal target organs. Administration of FTY only prior to transplantation inhibited GVHD, indicating that the primary function of FTY may be targeted to host cells. FTY was additive with regulatory T cells for GVHD inhibition. FTY slightly impaired but did not abrogate a graft-versus-leukemia (GVL) effect against C1498, a myeloid leukemia. Our data further define the mechanisms of action and provide insight as to the potential clinical uses of FTY in allogeneic bone marrow transplant recipients.
The Myth of Moccasin Bluff: Rethinking the Potawatomi Pattern
Authors: O'Gorman Jodie A.
Published: July 2007

In a 1969 Ethnohistory article James Fitting and Charles Cleland developed an ethnographic model derived from the Potawatomi Pattern of large, semipermanent villages with an emphasis on corn agriculture to interpret earlier cultural adaptations within the Carolinian biotic province. This and other works created and perpetuated the Myth of Moccasin Bluff, which identifies the Moccasin Bluff site in southwestern Michigan as an example of an agricultural village of the Potawatomi Pattern. In this essay the fit between the archaeological record and the Potawatomi Pattern analogue is reexamined, and the validity of transposing the historically observed focus on agriculture into more ancient history is critiqued. An alternative research framework for modeling ancient Potawatomi history is outlined.
Whitemen, the Ipili, and the City of Gold: A History of the Politics of Race and Development in Highlands New Guinea
Authors: Jacka Jerry K.
Published: July 2007

Ipili speakers in the highlands of Papua New Guinea creatively use the category “whiteman” both to structure their longing for socioeconomic progress and development and to critique the very institutions associated with development that they desire. This article explores the history of Ipili-white interactions from first contact in the 1930s, through the rise of indigenous mining, and up to the present to trace how “whiteness” as a category has transformed Ipili understandings of whites and the West. Today the Ipili, as landowners associated with the Porgera gold mine, are intimately entangled with development and its benefits and ills, which have prompted debate over how to build a “modern” town in the highlands.
Polarity proteins PAR6 and aPKC regulate cell death through GSK-3β in 3D epithelial morphogenesis
Authors: Kim Minji , Datta Anirban , Brakeman Paul , Yu Wei , Mostov Keith E.
Published: July 2007

Epithelial cells are polarized, with an apical surface facing a lumen or outer surface and a basolateral surface facing other cells and extracellular matrix (ECM). Hallmarks of epithelial carcinogenesis include loss of polarity, as well as uncontrolled proliferation and resistance to apoptosis. Are these features controlled by a common molecular mechanism? The partitioning-defective 3 (PAR3)-PAR6-atypical PKC (aPKC) complex is a master regulator that controls polarization in many animal cells. Here we show that PAR6 is involved in apoptosis by regulating aPKC and glycogen synthase kinase 3β (GSK-3β) activity. During epithelial morphogenesis in 3D culture of Madin-Darby canine kidney (MDCK) cells, expression of an N-terminally deleted PAR6 (PAR6ΔN) leads to a significant increase in caspase-dependent cell death by downregulating aPKC activity. Accordingly, inhibition of aPKC in wild-type (WT) MDCK cells with either a cell-permeable PKCζ pseudosubstrate or RNAi promotes apoptosis, which suggests that PAR6 regulates apoptosis via an aPKC-mediated pathway. GSK-3β, a substrate of aPKC, is hyper-activated by expressing PAR6ΔN. GSK-3β inhibitors block PAR6ΔN-induced apoptosis while expression of constitutively active GSK-3β (S9A) promotes apoptosis, which is rescued by ectopic expression of aPKC. We conclude that a PAR6-aPKC-GSK-3β mechanism links cell polarity and apoptosis.
CDK11p58 is required for the maintenance of sister chromatid cohesion
Authors: Hu Dongli , Valentine Marcus , Kidd Vincent J. , Lahti Jill M.
Published: July 2007

Cyclin-dependent kinase 11 (CDK11) mRNA produces a 110-kDa protein (CDK11p110) throughout the cell cycle and a 58-kDa protein (CDK11p58) that is specifically translated from an internal ribosome entry site sequence during G2/M. CDK11p110 is involved in transcription and RNA processing, and CDK11p58 is involved in centrosome maturation and spindle morphogenesis. Deletion of the CDK11 gene in mice leads to embryonic lethality at E3.5, and CDK11-deficient blastocysts exhibit both proliferative defects and mitotic arrest. Here we used hypomorphic small interfering RNAs (siRNAs) to demonstrate that, in addition to playing a role in spindle formation and structure, CDK11p58 is also required for sister chromatid cohesion and the completion of mitosis. Moderate depletion of CDK11 causes misaligned and lagging chromosomes but does not prevent mitotic progression. Further diminution of CDK11 caused defective chromosome congression, premature sister chromatid separation, permanent mitotic arrest and cell death. These cells exhibited altered Sgo1 localization and premature dissociation of cohesion complexes. This severe phenotype was not corrected by codepletion of CDK11 and either Plk1 or Sgo1, but it was rescued by CDK11p58. These findings are consistent with the mitotic arrest we observed in CDK11-deficient mouse embryos and establish that CDK11p58 is required for the maintenance of chromosome cohesion and the completion of mitosis.
Theoretical Study of the Change in the Magnetism and Conductivity of Diethylspirobiphenalenyl
Authors: Takenaka Mao , Taniguchi Takeshi , Kawakami Takashi , Kitagawa Yasutaka , Okumura Mitsutaka , Yamaguchi Kizashi
Published: July 2007

The J values of the Heisenberg model and t and Ueff values in the Hubbard model have been evaluated by the Kohn–Sham density functional theory (KS-DFT) for dimeric pairs of diethyl-spirobiphenalenyl. The Quantum Monte Carlo (QMC) simulation has been carried out with the calculated J values to evaluate the magnetic susceptibility for this molecular crystal, reproducing the experimental tendency. The band gaps estimated by using t and Ueff values are also consistent with the experiment on conductivity.
N,N′-Dichlorobis(2,4,6-trichlorophenyl)urea (CC-2): An Efficient Reagent for N-Chlorination of Amino Esters, Amide, and Peptides
Authors: Sathe Manisha , Karade Hitendra , Kaushik Mahabir Parshad
Published: July 2007

A simple, efficient, and rapid protocol for N-chlorination of various protected amino esters, amides, and peptides has been described. N,N′-dichlorobis(2,4,6-trichlorophenyl)urea has been used as a chlorinating agent and transformation takes place rapidly in mild conditions with quantitative yields.
RhCl3/Amine-catalyzed Cyclotrimerization of Alkynes
Authors: Yoshida Kenta , Morimoto Ichiro , Mitsudo Koichi , Tanaka Hideo
Published: July 2007

RhCl3/amine was found to be an efficient catalyst for the cyclotrimerization of alkynes. The [2+2+2] cyclotrimerization of internal alkynes proceeded smoothly to afford hexa-substituted benzenes regioselectively in moderate to high yields.
Biliary secretion in conscious rabbits: surgical technique
Authors: Jimenez R. , Esteller A. , Lopez Maria Abdona
Published: July 2007

This double recurrent choledoco-choledocal biliary fistula is a new surgical procedure which allows the study of biliary secretion in rabbits while avoiding influences arising from anaesthesia and enterohepatic circulation of bile salts.
Canine Adenovirus Type 1 Infection of a Eurasian River Otter (Lutra lutra)
Authors: Park N. Y. , Lee M. C. , Kurkure N. V. , Cho H. S.
Published: July 2007

A 10-year-old female Eurasian river otter ( Lutra lutra) died after prolonged anorexia and weight loss in the Seoul Grand Park Zoo, Seoul, Republic of Korea. On necropsy, the liver was found to be swollen and friable with 1 lobe enlarged and necrotic. The other organs showed no significant alterations except for mild atrophy of the right kidney. Microscopically, there was multifocal hepatic necrosis. The hepatocytes around the necrotic areas were swollen and contained large basophilic intranuclear inclusions. Periportal infiltration by plasma cells and lymphocytes was also evident. Transmission electron microscopy revealed characteristic hexagonal virus particles sized approximately 70 nm in diameter in the nuclei of the hepatocytes, which were consistent with an adenovirus. Polymerase chain reaction of the formalin-fixed, paraffin-embedded liver sections was used to determine whether the virus was either the canine adenovirus type 1 (CAV-1), canine adenovirus type 2 (CAV-2), or some other viral agent. The results of these tests showed that the virus was CAV-1. To our knowledge, this is the first report on a CAV-1 infection in an otter.
The Bro1-Domain Protein, EGO-2, Promotes Notch Signaling inCaenorhabditis elegans
Authors: Liu Ying , Maine Eleanor M
Published: July 2007

In Caenorhabditis elegans, as in other animals, Notch-type signaling mediates numerous inductive events during development. The mechanism of Notch-type signaling involves proteolytic cleavage of the receptor and subsequent transport of the receptor intracellular domain to the nucleus, where it acts as a transcriptional regulator. Notch-type signaling activity is modulated by post-translational modifications and endocytosis of ligand and receptor. We previously identified the ego-2 (enhancer of glp-1) gene as a positive regulator of germline proliferation that interacts genetically with the GLP-1/Notch signaling pathway in the germline. Here, we show that ego-2 positively regulates signaling in various tissues via both GLP-1 and the second C. elegans Notch-type receptor, LIN-12. ego-2 activity also promotes aspects of development not known to require GLP-1 or LIN-12. The EGO-2 protein contains a Bro1 domain, which is known in other systems to localize to certain endosomal compartments. EGO-2 activity in the soma promotes GLP-1 signaling in the germline, consistent with a role for EGO-2 in production of active ligand. Another C. elegans Bro1-domain protein, ALX-1, is known to interact physically with LIN-12/Notch. We document a complex phenotypic interaction between ego-2 and alx-1, consistent with their relationship being antagonistic with respect to some developmental processes and agonistic with respect to others.
Hybridization in Large-Bodied New World Primates
Authors: Cortés-Ortiz Liliana , Duda Thomas F , Canales-Espinosa Domingo , García-Orduña Francisco , Rodríguez-Luna Ernesto , Bermingham Eldredge
Published: July 2007

Well-documented cases of natural hybridization among primates are not common. In New World primates, natural hybridization has been reported only for small-bodied species, but no genotypic data have ever been gathered that confirm these reports. Here we present genetic evidence of hybridization of two large-bodied species of neotropical primates that diverged ∼3 MYA. We used species-diagnostic mitochondrial and microsatellite loci and the Y chromosome Sry gene to determine the hybrid status of 36 individuals collected from an area of sympatry in Tabasco, Mexico. Thirteen individuals were hybrids. We show that hybridization and subsequent backcrosses are directionally biased and that the only likely cross between parental species produces fertile hybrid females, but fails to produce viable or fertile males. This system can be used as a model to study gene interchange between primate species that have not achieved complete reproductive isolation.