bluuebunny/crossref_metadata_2025 huggingface dataset:
Throughput Considerations for In-Situ Doped Embedded Silicon Carbon Stressor Selectively Grown into Recessed Source Drain Areas of NMOS Devices
Authors: Bauer Matthias , Zhang Yangting , Weeks Doran , Brabant Paul , Italiano Joe , Machkaoutsan Vladimir , Thomas Shawn G.
Published: May 2008

In this paper we calculate throughput based on recipe overhead (chamber etch, wafer load, wafer bake, cool down, unload) and deposition time for "true" SEG or the core cycle time (deposition, purge, etch, purge times) for a CDE process. In the latter case an average, effective growth rate (GR) can be extracted by dividing the deposited thickness per cycle by the cycle time. In high volume manufacturing (HVM) high SEG GR are necessary for high throughput and low Cost of Ownership (CoO). High GR also enable high substitutional carbon levels [C]sub in dilute Si:C alloys. In this work all experiments were exclusively performed using Silcore® (ASM trademarked version of Si3H8). Due to the high GR at low process temperature, high [C]sub and low films resistivities can be obtained independent of the two different Cl containing etch chemistries that were used in this study. The main challenge of using Cl2 compared to the ASM proprietary etch chemistry is the 25-30 times lower etch rate selectivity (~7 vs. ~190) of a-SiCP over epi-SiCP. As a result of the low etch rate selectivity using a Cl2 etch chemistry, a significant portion of the epitaxial SiC:P is also etched with the a-SiCP. This results in a low effective growth rate which has a deleterious impact to throughput.
Critical Analysis of Different Techniques for Measuring Strain in Si1-yCy Layers Grown by CVD on a Si Substrate
Authors: Cherkashin Nikolay , Gouye Adrien , Hue Florian , Houdellier F. , Hytch M. J. , Kermarrec O. , Rouchon D. , Burdin M. , Holliger P. , Claverie Alain
Published: May 2008

In this work, we performed quantitative measurements of strain in structures consisting of a 30 nm-thick Si1-yCy layer grown by chemical vapour deposition (CVD) on a Si (001) substrate. Total C concentrations vary from 0.67 to 2%. Geometric phase analysis (GPA) of high-resolution transmission electron microscopy (HR TEM) cross-section images and convergent-beam electron diffraction (CBED) with a nanometer resolution as well as Raman spectroscopy and high-resolution X-ray diffraction with a micro- and millimeter resolutions, respectively, were used to deduce the strain within these Si1-yCy layers. These results were compared with the predictions of elasticity theory. Particular interest is paid to the formation of the structural defects within Si1-yCy layers as a function of C concentration, growth temperature and incorporated strain.
Heavily Phosphorus Doped Silicon Junctions for nMOS Applications
Authors: Chopra Saurabh , Ye Zhiyuan , Zojaji Ali , Kim Yihwan , Kuppurao Satheesh
Published: May 2008

Epitaxially grown Silicon Carbon (Si:C) in recessed junction regions has been shown to induce tensile stress in the nMOS channel and thereby enhance the transistor performance. In addition to the stress induced in the channel, this technology also needs to achieve low resistivity junctions for widespread use. This work discusses epitaxially grown heavily doped Si/ Si:C layers which can be used in nMOS junctions and can address both these requirements. Si:C epitaxial layers are shown to have phosphorus concentrations as high as 1.25 X 10^21 cm^-3 with resistivities as low as 0.3 mOhm.cm. Applications of these layers can range from Si:P cap layers for low series resistance to Si:PC layers for inducing stress in the nMOS channel.
Hole Mobility Behavior in Strained SiGe-on-SOI p-MOSFETs
Authors: Shim Tae-Hun , Kim Seong-Je , Lee Gon-Sub , Kim Kwan-Su , Cho Won-Ju , Park Jea-Gun
Published: May 2008

A compressive strained SiGe channel grown-on-SOI structure which can be applicable to next generation high performance C-MOSFETs was applied to p-MOSFETs. The mobility behavior depending on effective fields, Eeff, was investigated by varying Ge concentrations in the SiGe layer. We confirmed that the mobility enhancement factor increases with both Ge concentration and Eeff, and quite depends on Eeff. In particular, we demonstrated that hole mobility enhancement factor at the effective fields of 0.13 MV/cm amounted to 1.51 for 34 at% Ge. In addition, we observed that the strain of 0.23 induced by 56.5-at% Ge concentration in SiGe grown-on-SOI structure could not increase hole mobility at the effective fields range from 0.05 to 0.13 MV/cm because of high density of dislocations.
Material and Integration Issues for Rare Earth Silicides as Gate and Diffusion Contacts in Advanced CMOS Technologies
Authors: D'Emic Christopher P. , Ohuchi Kazuya , Murray Conal , Lavoie Christian , Scerbo Christopher , Carruthers Roy , Besser Paul R. , Yang Bin
Published: May 2008

In an integration scheme where the nFETs and pFETs of CMOS devices are silicided with different materials (Dual Silicides), rare-earth erbium (Er) and ytterbium (Yb) silicides are potential candidates for contacts to n-Si because of their lower Schottky barrier heights, as compared to more conventional nickel and cobalt silicides. [1-3] Although the lower Schottky barrier across the silicide/n-silicon interface results in reduced contact resistivity, the microstructure can exhibit defects and morphology issues [3-7] which affect device integrity and may contribute to contact resistance degradation. [8] In this study, we compared the material and integration properties of Er and Yb silicides with those of Ni (Pt-alloyed) silicide. Using four point probe, AFM, optical inspection and SEM, we compared the silicides using sheet resistance, surface morphology, defects density and ease of formation in narrow lines. We found that the silicide morphology is affected by several process parameters such as the type of metal deposition process (sputtering vs. evaporated) and the anneal formation temperature. The silicides were also tested for their ability to withstand aggressive processing after their formation. The processes tested included exposure to PECVD plasma, contact hole reactive ion etching and forming-gas annealing. The rare-earth and Ni(Pt) silicides showed similar stability upon processing. Lastly, we quantified the residual metal remaining on dielectric surfaces after silicide processing. Overall, Er silicide showed better performance than Yb silicide. By optimizing various elements of the silicidation process, higher quality silicide films can be achieved for evaluation as suitable nFet contacts.
A Study on the Formation Processes and Microstructures of Ni-Silicide Films on Epi-Si1-xCx
Authors: Yoo Jung-Ho , Chang Hyun-Jin , Cho Mann-Ho , Lee Tae-Wan , Ko Dae-Hong
Published: May 2008

We investigated the silicide formation in the Ni/epi-Si1-xCx systems. Ni films were deposited on epi-Si1-xCx/Si substrates by DC magnetron sputtering and processed at various temperatures. The sheet resistance of the silicide from the Ni/epi-Si1-xCx systems was maintained at low values compared to Ni/Si systems. The stability of the silicide layer in Ni/epi-Si1-xCx system is explained by the presence of the small amount of C in the Ni-silicide layer or at the grain boundaries.
Chemical Vapor Deposition Pt-Ni alloy Using Pt(PF3)4 and Ni(PF3)4
Authors: Ishikawa Masato , Muramoto Ikuyo , Machida Hideaki , Imai Satoshi , Ogura Atsushi , Ohshita Yoshio
Published: May 2008

The decomposition rates of Ni(PF3)4 and Pt(PF3)4 on the growing surface, which are useful for Pt-Ni alloy thin film deposition, were studied by using the macro cavity analysis. The activation energies for these gas-decomposition were obtained 1.0 and 0.86eV, respectively. The Pt source requires the smaller thermal energy. Therefore, it is suggested that when the Pt-Ni alloy film at the high temperatures, the Pt/Ni ratio of the film deposited in the trench will swiftly decrease as increasing the distance from the open area, as well as the trench quality decreases.
The Analysis of the Cu Surface Morphology Evolution During Electropolishing
Authors: Shivareddy Shyamala , Bae Sang -E. , Brankovic Stanko R.
Published: May 2008

The work examining the evolution of the rough Cu surface morphology during the electropolishing process is presented. The surface width, w, is measured for different length scale, l, and time of the electropolishing experiments, t, and the data are analyzed within the scope of the scaling concept and predictions of electropolishing theory. The experimental data indicates that surface width as a function of the length scale maintains two scaling regimes (l {less than or equal to} lC; w ~ lC α and, l {greater than or equal to} lC; w ≈ const). The roughness exponents (α), extracted from the data obtained for different polishing times show the time dependence described by linear regression. The decrease of surface width with polishing time is well described by exponential decay predicted by the mathematical model of an ideal electropolishing process. The semi-empirical function is proposed to describe the surface width decrease during the electropolishing and the example of its practical application is discussed.
Effect of Organic Amine in Colloidal Silica Slurry on Polishing-rate Selectivity of Copper to Tantalum-nitride Film in Copper Chemical Mechanical Planarization
Authors: Park Jin-Hyung , Cui Hao , Hwang Hee-Sub , Paik Ungyu , Park Hyung-Soon , Park Jea-Gun
Published: May 2008

We have investigated the polishing rates and selectivity between Cu and TaN films with H2O2 and complexing agents, organic amine such as Alanine and polyacrylamide (PAM) are given as an alkaline pH, and the role of amine functional groups on the possible mechanism is discussed.
Enhanced Thermal Dissipation and Light Output of GaN/Sapphire Light-Emitting Diode by Direct Cu Electroplating
Authors: Chiang C. C. , Horng R. H. , Wuu D. S. , Hsiao H. Y. , Hsieh C. Y. , Lin H. I.
Published: May 2008

Using the self-alignment lithography and copper (Cu) electroplating techniques, a lateral-electrodes GaN light-emitting diode (LED) with a micro reflective cup and heat spreader has been demonstrated. In this work, the photoresist is used to be the electroplating forms and to produce micro reflective cup and 9 mm2 heat spreader. Under 1 A current driving, the LEDs with direct thermal spreader has an output power of 700 mW and a power conversion efficiency is upto 2 times as compared with that of the lateral-electrodes LEDs only on sapphire without current spreader. The performance of LEDs with a micro reflective cup and heat spreader is almost the same (even better) as the vertical-electrodes LEDs on Cu substrate.
Group-III Nitride P-Ttype Nanowire Heterostructure Field Effect Transistors
Authors: Mastro Michael , Simpkins Blake , Twigg Mark , Tadjer Marko R. , Holm R. T. , Eddy Charles
Published: May 2008

A two-step deposition process was developed in a metal organic chemical vapor deposition system to create a defect-free p-type structure consisting of a GaN nanowire (NW) core surrounded by a distinct AlGaN radial shell. The m-plane growth direction yields a nanowire with an isosceles triangular cross section with two identical {-110-1} facets and a third (0001) facet. The AlGaN shell introduces a polarization-induced sheet charge at the AlGaN/GaN interface and may shield the NW from surface-state induced depletion. Transmission electron microscopy confirmed that single-component NWs and sufficiently thin NW heterostructures are free of extended defects. High hole currents and current modulation were demonstrated with back-gated NW transistor structures.
Etching Rate Behavior of 4H-Silicon Carbide Using Chlorine Trifloride Gas
Authors: Miura Yutaka , Katsumi Yusuke , Tanaka Keiko , Oda Satoko , Habuka Hitoshi , Gao Yuan , Fukai Yasushi , Fukae Katsuya , Kato Tomohisa , Okumura Hajime , Arai Kazuo
Published: May 2008

Dry etching of 4H-silicon carbide (SiC) is studied using chlorine trifluoride gas at 673-973K and atmospheric pressure in a horizontal reactor. The etch rate of C-face and Si-face of 4H-SiC can be greater than 10 um/min at substrate temperatures higher than 723 K. The etch rate of Si-face is lower than that of C-face. The etch rate increases with the chlorine trifluoride gas flow rate. The etched surface of Si-face shows many pits having a hexagonal edge shape and tends to be rough. However, the C-face maintains a very smooth surface after the etching. The average roughness of the etched surface tends to be low at the higher temperatures. The etch rate behavior is discussed from the view points of the transport phenomena in the reactor and the chemical process at the substrate surface; their rate constants are obtained.
A Self-Driven CM-n-TiO2 / CM-p-WO3 Photoelectrochemical Cell for Water Splitting
Authors: Shaban Yasser , Khan Shahed U.
Published: May 2008

A self-driven carbon modified CM-p-WO3 / CM-n-TiO2 photoelectrochemical cell (PEC) was found to split water under illumination intensity of 100 mW cm-2 from a solar simulator with a global AM 1.5 filter. This photoelectrochemical cell shows a photocurrent density of 0.4 mA cm-2 at zero bias. The PEC was found to split water directly upon illumination without the need of using bias potential from any external source. The water splitting efficiency of this self-driven PEC was found to be 0.5 % under solar simulated light illumination with a global AM 1.5 filter (1 sun).
Design and Fabrication of 64x64 MWIR LED Array for Infrared Scene Simulation
Authors: Das Naresh C. , Chang Wayne
Published: May 2008

We report here a research effort of the fabrication of interband cascade MBE growth material based 64x64 LED array with peak emission wavelength of mid infrared @ 3.8 micron. The light emission is observed from bottom side through the substrate. We use interband cascade epitaxial structures for the LED experiments on both p- and n-type substrates. Good light-current-voltage characteristics has been observed on LED array. The detailed array characterization including maximum apparent emission temperature, uniformity and reliability will be discussed.
Analytical and Structural Investigations of the Metal-Enhanced Oxidation of Sic-MOS Structures
Authors: Lee Unchul , Zheleva Tsvetanka , Lelis Aivars , Duscher Gerd , Liu Fude , Das Mrinal , Scofield James
Published: May 2008

The purpose of this work is to study the chemical and structural variations across the MEO SiO2/4H-SiC interfaces in order to compare results with standard thermally oxidized and NO annealed samples, and correlate these process variations with the improved mobility of the SiC MOS devices. The MEO SiC-MOS structures were studied via X-ray Photo-Electron Spectroscopy (XPS), EELS and TEM. Both XPS and EELS analyses indicate that the major elements C, Si and O go through changes of their chemical states in the interface transition regions from SiC to SiO2. Structural characterization with TEM reveal contrast changes at the near interface regions that indicate local chemical and/or stoichiometric variations, but no structural degradation or amorphization of the top few atomic SiC layers. XPS depth profile studies suggest that these changes have occurred up to ~ 200 nanometers deep down into the SiC substrate.
Room Temperature Deposited Enhancement Mode and Depletion Mode Indium Zinc Oxide Thin Film Transistors
Authors: Wang Yu-Lin , Lim Wantae , Covert Lance , Anderson Travis , Lin Jenshan , Pearton Stephen J. , Norton D , Ren F.
Published: May 2008

Enhancement mode and depletion mode indium zinc oxide (IZO) thin film transistors (TFTs) were fabricated on glass substrates using rf magnetron sputtering deposition at room temperature. Plasma enhanced chemical vapor deposited SiO2 or SiNx was used as the gate insulator. The enhancement mode TFTs showed excellent pitch-off and the threshold voltage was 0.75V. The drain current on-to-off ratio was >106. The maximum field effect mobility in the channel was 308 cm2.V-1.s-1. The depletion mode TFTs had a threshold voltage of -2.5V. The drain current on-to-off ratio was >105. The maximum field effect mobility in the channel was 14.5 cm2.V-1.s-1.
Demonstration of Hydrogen Effects on ZnO LEDs in Current-Voltage and Electroluminescence Characteristics
Authors: Wang Yu-Lin , Kim Hyun-Sik , Norton D , Pearton Stephen J. , Ren F.
Published: May 2008

Hydrogen effects on the electrical and optical properties of p-i-n ZnO light emitting diodes (LEDs) were investigated. There were no diode characteristics or light emission observed unless the structures were annealed at 350 {degree sign}C after fabrication. Annealed diodes showed band-edge electroluminescence (385nm) and a broad defect band with a peak at 930nm at room temperature. A hydrogen plasma was used to deliberately introduce hydrogen into the annealed p-i-n ZnO LEDs to verify its effects on diode characteristics. With hydrogen plasma treatment, the diode reverse-bias leakage current increased and both the turn-on voltage and the intensity of the electroluminescence decreased. Moreover, the effects of moisture, water, and phosphoric acid solution on the annealed diode characteristics were also investigated and significant degradation of electrical and optical properties were observed in all cases. These results point to the sensitivity of ZnO LEDs to processing conditions and measurement ambient.
Control of Crystalline Microstructures in Metal Gate Electrodes for Nano CMOS Devices
Authors: Ohmori Kenji , Chikyow T. , Hosoi Takuji , Watanabe Heiji , Nakajima Kiyomi , Adachi Tetsuya , Ishikawa Ayako , Sugita Yoshihiro , Nara Yasuo , Ohji Yuzuru , Shiraishi Kenji , Yamabe Kikuo , Yamada Keisaku
Published: May 2008

We propose a novel approach to control the effective work function by taking advantage of crystal structures in metal gate electrodes. The crystal structures determine the predominant material elements at the metal/high-k interface. We have found that, in a Ru-Mo alloy system, a randomly-oriented Ru (fcc) structure promotes the segregation of Mo at the interface, enabling us to achieve a wide controllability of flatband voltage by the amount of 0.6-0.8 eV. In addition, the segregation of Mo within a Ru-rich electrode is a key to reducing Fermi level pinning at the metal/HfSiON interfaces.
Virtual Nature Experiences as Emotional Benefits in Green Product Consumption
Authors: Hartmann Patrick , Apaolaza-Ibáñez Vanessa
Published: May 2008

This article suggests that consumer exposure to nature's media representation in green product advertising may lead to emotional experiences during product consumption that are analogue to those experienced in “real” nature. These “virtual nature experiences” may constitute emotional consumption benefits in consumer's perception. Two further kinds of emotional consumption experiences related to environmental products are identified: the feeling of well-being from acting in an altruistic way (“warm glow”), and self-expressive benefits. The influences of the proposed consumption experiences on the consumer's attitude toward the product are analyzed in the scope of a survey of consumer perceptions of three competing energy brands, one of them positioned as a green energy brand. Results reveal mostly positive influences on product attitude, with the particular pattern of effects being significantly moderated by the environmental attitudes of the respondents. Virtual nature experiences turn out to wield the most significant influences, regardless of the consumer's degree of environmental attitudes.
Analytical Reviews: Antifungal Therapies in the Intensive Care Unit
Authors: Chowdhry Ranjan , Marshall William L.
Published: May 2008

Fungal infections are increasing nationwide, paralleling increases in the number of immunosuppressed hosts. Most of the candida infections seen in the intensive care unit are likely due to iatrogenic factors such as hyperalimentation, catheters, broad-spectrum antibiotics, and postprocedure complications that are prevalent in intensive care unit patients. Delays in appropriate therapy are common and may compromise care. Fortunately, the recognition of several clinical syndromes in the intensive care unit that require specialized treatment can improve outcomes. The issue of antifungal prophylaxis has to be balanced against issues of resistance, and current guidelines are reviewed here for prophylactic use of fluconazole only in selected intensive care unit patients. Finally, several new antifungal agents are available to treat the emerging resistant fungi, with better toxic/therapeutic ratios than in the past. Thus, there are an increasing number of safer and more effective options for treating fungal infections in the intensive care unit.
Subclinical Anxiety Symptoms, Sleep, and Daytime Dysfunction in Older Adults With Primary Insomnia
Authors: Spira Adam P. , Friedman Leah , Aulakh Jasdeep S. , Lee Tina , Sheikh Javaid I. , Yesavage Jerome A.
Published: May 2008

Both insomnia complaints and anxiety disorders are common in older adults, and are associated with poor daytime functioning. The present study investigated whether subclinical levels of anxiety were associated with sleep disturbance and daytime functioning in older adults who met diagnostic criteria for primary insomnia, and therefore did not meet criteria for depression or an anxiety disorder. After adjustment for depressive symptoms, elevated state anxiety was associated with higher levels of wake after sleep onset (measured by both actigraphy and sleep log) and shorter sleep onset latency (measured by sleep log). Higher levels of trait anxiety were associated with greater wake after sleep onset (measured by sleep log). Elevated state and trait anxiety were associated with worse social functioning, and higher levels of trait anxiety were associated with worse role functioning. Thus, subclinical anxiety symptoms may be an important target for clinical intervention to improve sleep and functioning in older adults with primary insomnia.
Neuropsychiatric Symptoms in Behavioral Variant Frontotemporal Dementia and Primary Progressive Aphasia
Authors: Banks Sarah J. , Weintraub Sandra
Published: May 2008

Neuropsychiatric symptoms are well defined in behavioral variant frontotemporal dementia but are not as well studied in primary progressive aphasia. This study compared caregiver reported neuropsychiatric symptoms in these 2 forms of dementia at short and long disease duration. Patients with behavioral variant frontotemporal dementia had more symptoms than patients with primary progressive aphasia. However, when divided by duration of disease, patients with primary progressive aphasia with long duration had a similar number of symptoms to patients with behavioral variant frontotemporal dementia at either duration. Furthermore, this group of patients with primary progressive aphasia had more symptoms typical of behavioral variant frontotemporal dementia and less mood-related symptoms which were more common in patients with primary progressive aphasia with shorter duration. This study illustrates the emergence of neuropsychiatric symptoms as primary progressive aphasia progresses and highlights the increasing overlap with behavioral variant frontotemporal dementia because the disease affects areas outside of the language network.
Learning and Generalization Tasks Predict Short-Term Cognitive Outcome in Nondemented Elderly
Authors: Myers Catherine E. , Kluger Alan , Golomb James , Gluck Mark A. , Ferris Steven
Published: May 2008

This study examines whether behavioral measures obtained in nondemented elderly can predict cognitive status at 2-year follow-up. Prior studies have established that delayed paragraph recall can help predict short-term risk for decline to mild cognitive impairment and Alzheimer disease. It was examined whether prediction accuracy can be improved by adding a discrimination-and-generalization task that has previously been shown to be disrupted in nondemented elderly with hippocampal atrophy, a risk factor for Alzheimer disease. Fifty nondemented, medically healthy elderly patients received baseline clinical diagnosis and cognitive testing; 2 years later, patients received a follow-up clinical diagnosis of normal, mild cognitive impairment, or probable Alzheimer disease. In all, 2 baseline variables, delayed paragraph recall and generalization performance, were predictive of follow-up outcome with sensitivity of 81% and specificity of 91%—better than the classification accuracy based on either of these measures alone. These preliminary results suggest that these behavioral tasks may be useful tools in predicting short-term cognitive outcome in nondemented elderly.
The Sense of Coherence in Hospitalized Cardiac and Cancer Patients
Authors: Bruscia Kenneth , Shultis Carol , Dennery Karen , Dileo Cheryl
Published: May 2008

The sense of coherence (SOC) is a measure of one's global orientation toward the world; it is the extent to which one perceives life as comprehensible, manageable, and meaningful. The study assesses the SOC of cardiac and cancer inpatients, and examines whether age, gender, race, education, and length of illness predict SOC. Participants comprise 172 patients (84 women, 88 men) at an urban hospital in the Northeastern United States, 122 with cardiac conditions and 50 with cancer. The mean age is 59.8. Results show that the SOC of cardiac and cancer patients is slightly lower than the general population. There are no differences in SOC between cardiac and cancer patients. Multiple regression shows that age and length of illness predict SOC ( R = .26, R2 = .07, p = .002); however because of the small effect size and collinearity, their exact contributions need further study. SOC does not vary according to gender, race, or education.
Healthy Youth Places: A Randomized Controlled Trial to Determine the Effectiveness of Facilitating Adult and Youth Leaders to Promote Physical Activity and Fruit and Vegetable Consumption in Middle Schools
Authors: Dzewaltowski David A. , Estabrooks Paul A. , Welk Greg , Hill Jennie , Milliken George , Karteroliotis Kostas , Johnston Judy A.
Published: May 2008

The Healthy Youth Places (HYP) intervention targeted increased fruit and vegetable consumption (FV) and physical activity (PA) through building the environmental change skills and efficacy of adults and youth. HYP included group training for adult school site leaders, environmental change skill curriculum, and youth-led FV and PA environment change teams. Sixteen schools were randomized to either implement the HYP program or not. Participants ( N =1,582) were assessed on FV and PA and hypothesized HYP program mediators (e.g., proxy efficacy) at the end of sixth grade (baseline), seventh grade (Postintervention Year 1), and eighth grade (Postintervention Year 2). After intervention, HYP schools did not change in FV but did significantly change in PA compared to control schools. Proxy efficacy to influence school PA environments mediated the program effects. Building the skills and efficacy of adults and youth to lead school environmental change may be an effective method to promote youth PA.
Campus Policing in America
Authors: Peak Kenneth J. , Barthe Emmanuel P. , Garcia Adam
Published: May 2008

This article compares the findings of a 2006 national survey of campus police agencies with one of 1986. Respondents were queried about agency titles; reporting lines; administrators' experience, education, tenure, and diversity; agency powers, jurisdiction, rank, training, activities/responsibilities, and relations with local police agencies; and involvement in disaster planning and terrorism readiness. It is concluded that considerable evolution has occurred over the past two decades; whereas constituencies, mission, and duties may differ, campus law enforcement agencies are part of and connected to the broader local law enforcement community and represent an essential component of postsecondary educational institutions.
Officer Race and Citizen-Reported Traffic Ticket Decisions by Police in 1999 and 2002
Authors: Gilliard-Matthews Stacia , Kowalski Brian R. , Lundman Richard J.
Published: May 2008

Does officer race affect the frequency with which citizens report receiving a ticket for a traffic law violation? According to citizens, is the effect of officer race on traffic tickets the same in 1999 and 2002 despite the increased attention given what has come to be called driving while Black? The present research answers these questions using citizen reports of their traffic stop encounters with police in 1999 and 2002. Net of important control variables, citizens report changes in the ways officer race affects traffic ticket decisions, most notably when viewed through the lens of intersections of officer race and driver race and ethnicity. Specifically, citizens report that Black police officers are less likely to ticket Black traffic law violators in 2002 than in 1999. In important contrast, White police officers are more likely to ticket all drivers of color in both 1999 and 2002.
Remarkable Color Changes Induced by Saccharide-responsive Sequential Release of Anionic Dyes
Authors: Kanekiyo Yasumasa , Yokozawa Takenori , Tao Hiroaki
Published: May 2008

A novel saccharide sensory system showing remarkable color changes has been developed. A copolymer containing boronic acid and cationic units was synthesized on which anionic dyes were adsorbed. By immersing the dye-adsorbed copolymer in aqueous saccharide solutions, blue and yellow dyes were sequentially released from the copolymer: with increasing saccharide concentration, the solution changed its color from colorless to blue, then changed into green.
Sensitive Detection and Identification of Organic Liquids Using the Second Derivative of Surface Plasmon Resonance Near-Infrared Spectra
Authors: Ikehata Akifumi , Ohara Kazuaki , Shinzawa Hideyuki , Ozaki Yukihiro
Published: May 2008

Sensitive detection of near-infrared (NIR) spectra of several organic liquids has been carried out by surface plasmon resonance (SPR) NIR spectroscopy. For all the liquids, 50- to 100-fold enhancements of the absorption peaks were obtained in the combination band region 4500–4000 cm−1 using a gold film with a thickness of 14 nm. The SPR peak shows up as an unnecessary broadband peak or trend in an SPR-NIR spectrum, and it was difficult to separate it from the absorption signals. In order to remove the contribution of SPR from the raw SPR-NIR spectrum, the second-order derivative has been employed. The second derivative of the SPR-NIR spectrum was reasonably comparable to that of the corresponding transmittance spectrum. Two simple algorithms for sample identification from the second-derivative data have been proposed. One is similarity, which directly compares the second-derivative spectrum of an unknown sample with that of a known reference sample. The other is fitness, which is defined as a ratio of the common part of absorption peak wavenumbers of the sample and the reference. Although both methods are unfit for the identification of a minor component in a mixture, a major component can be definitely identified by choosing an informative wavenumber region. It was found that the wavenumber region 4250–4080 cm−1 is especially useful for the identification of similar molecules such as normal alkanes.
Two-Dimensional Correlation Analysis Study of the Photo-Induced Molecular Reorientations of Photosensitive Polyester Film Containing 1,4-Phenylenediacryloyl Units in the Backbone
Authors: Chae Boknam , Lee Seung Woo , Jung Young Mee , Ree Moonhor , Kim Seung Bin
Published: May 2008

The photochemical reaction and molecular reorientation of a novel photosensitive polyester, poly[oxy(4- n-butyl-3,5-benzoate)oxy-1,4-phenylenediacryloyl] (PPDA-C4BZ), which contains n-butyl side groups and 1,4-phenylenediacryloyl units (PDA chromophores) in the main chain, are reported in detail. We applied two-dimensional (2D) correlation analysis for the infrared (IR) and ultraviolet (UV) absorption spectra of nanoscaled films of PPDA-C4BZ to establish the sequence of the photo-induced segmental reorientations that result from UV irradiation. The photochemical reaction was found to have a greater effect on the polymer's main chains than on its side groups and to induce the reorientation of the polymer molecules. In particular, a cycloaddition process occurs first in the PDA chromophore units and then the local reorientation of the polymer molecules is induced. Namely, such photodimerization of the PDA chromophores induces the molecular reorientations of the PDA chromophores and the benzoate units in the main chain. The photo-induced molecular reorientations occur in the following sequence: photodimerization → benzoate units → PDA chromophores → n-butyl side groups. In addition, a two-dimensional map of the first derivatives of the UV absorption spectra with respect to the exposure energy provided evidence of the formation of head-to-head aggregates (i.e., H-aggregates) of PPDA-C4BZ molecules.
Effect of Conformation and Drop Properties on Surface-Enhanced Raman Spectroscopy of Dried Biopolymer Drops
Authors: Esmonde-White Karen A. , Le Clair Stephanie V. , Roessler Blake J. , Morris Michael D.
Published: May 2008

Biofluids are complex solutions consisting of small ions and large biopolymers such as DNA, proteins, or proteoglycans. Biopolymers affect fluid properties but their effect on drop deposition has not been examined. Hyaluronic acid (HA), an important component in synovial fluid, was chosen as a model biopolymer, and examined using surface-enhanced Raman spectroscopy (SERS). Nanoliter volumes of HA solutions were dried onto a patterned SERS substrate and spectra were collected from the dried hyaluronic acid drops with a near-infrared Raman microscope. Characteristic hyaluronic acid bands were examined. Capillary viscometry measured properties of HA solutions, and entanglement behavior was also modeled using scaling theory principles. Viscosity measurements were incorporated into models of suspended particle droplets to account for the effect of inter-chain attraction on droplet formation. Microscope images were used to evaluate the shape of the dried drop. Relative drop thickness was estimated from concentric rings found at drop edges using established models of light interference by thin films. We found SERS spectra were sensitive not only to polymer conformation, but also to type of deposition (ring versus uniform), and the thickness of the resulting deposition. These data suggest an approach to elucidate the effects of biopolymers and dehydrated biofluids on SERS analysis.
Time-Resolved Optical Spectroscopy of Wood
Authors: D'Andrea C. , Farina A. , Comelli D. , Pifferi A. , Taroni P. , Valentini G. , Cubeddu R. , Zoia L. , Orlandi M. , Kienle A.
Published: May 2008

We have proposed and experimentally demonstrated that picosecond time-resolved optical spectroscopy in the visible/near-infrared (NIR) region (700–1040 nm) is a useful technique for noninvasive characterization of wood. This technique has been demonstrated on both softwood and hardwood samples treated in different ways simulating the aging process suffered by waterlogged woods. In all the cases, alterations of absorption and scattering spectra were observed, revealing changes of chemical and structural composition.
Investigation of Polypeptide Conformational Transitions with Two-Dimensional Raman Optical Activity Correlation Analysis, Applying Autocorrelation and Moving Window Approaches
Authors: Ashton L. , Blanch E. W.
Published: May 2008

The study of conformational transitions in polypeptides is not only important for the understanding of folding mechanisms responsible for the self-assembly of proteins but also for the investigation of the misfolding of proteins that can result in diseases including cystic fibrosis, Alzheimer's, and Parkinson's diseases. Our recent studies developing two-dimensional Raman optical activity (ROA) correlation analysis have proven to be successful in the investigation of polypeptide conformational transitions. However, the complexity of the ROA spectra, and the 2D correlation synchronous and asynchronous plots, makes data analysis detailed and complex, requiring great care in interpretation of 2D correlation rules. By utilizing the 2D correlation approaches of autocorrelation and moving windows it has been possible to gain further information from the ROA spectral data sets in a simpler and more consistent way. The most significant spectral intensity changes have been easily identified, facilitating appropriate interpretation of synchronous plots, and transition phases have been identified in the moving window plots, directly relating spectral intensity changes to the perturbation.
Characterization of Carbon-Containing Aerosolized Drugs Using Laser-Induced Breakdown Spectroscopy
Authors: Mukherjee Dibyendu , Cheng Meng-Dawn
Published: May 2008

Aerosolized drug delivery methods have increasingly become popular for pharmaceutical applications. This is mainly due to their ease of application and the more recent advancements incorporating nano-sized generation of particles that find deeper penetration routes and more efficient administration of the drug to specific target organs. Their effectiveness heavily relies on the uniformity of the chemical composition of these aerosolized drugs. Thus, it calls for a real-time on-line analytical tool that can accurately characterize the chemical constituents of the drug powder particles generated to ensure a stringent quality control. We present laser-induced breakdown spectroscopy (LIBS) for the first time as an efficient analytical tool to carry out on-line quantitative chemical characterization of aerosolized drugs. We used three different carbon based aerosolized drugs, namely L-ascorbic acid 2-phosphate sesquimagnesium salt hydrate (C6H9Mg1.5O9P·xH2O), Iron(II) L-ascorbate (C12H14FeO12), and DL-pantothenic acid hemicalcium salt (C9H16NO5·0.5Ca) for our quantitative LIBS studies here. Our results show that LIBS can effectively estimate the quantitative ratios of carbon to various trace elements for each of these drugs, thereby enabling on-line unique characterization of individual aerosolized drugs. The quantitative LIBS technique predicted the [C]/[Mg], [C]/[Fe], and [C]/[Ca] ratios as 4.02 ± 0.76, 12.42 ± 2.36, and 18.47 ± 4.39 for each of the above aerosolized drugs, respectively. Within error limits, we find these ratios in good agreement with the respective stoichiometric values of 4, 12, and 18 corresponding to the drugs above. Thus, the work demonstrated the utility and validity of LIBS in accurate on-line identification of drug powders during real-time manufacturing processes.
Development of a Reversible Bending Fatigue Test Bed to Evaluate Bulk Properties Using Sub-Size Specimens
Authors: De P. S. , Obermark C. M. , Mishra R. S.
Published: May 2008

A non-standard fully reversible bending fatigue test bed of fixed displacement amplitude type was designed. A sub-size sample similar in design to the standard ASTM B593 sample was used to evaluate the high cycle bend fatigue behavior of 7075-T6 sheet specimens. Fatigue life was determined at four stress levels of 300, 240, 220, and 190 MPa at a stress ratio of −1.
Terra Madre 2006: Political Theater and Ritual Rhetoric in the Slow Food Movement
Authors: peace adrian
Published: May 2008

The biannual mega-event of Terra Madre is now established as the political flagship of the Slow Food movement. It assembles in Turin the leading cosmopolitan figures of this neo-tribal, post modern organization, along with several thousand of its ordinary members, who were drawn in 2006 from the ranks of food producers, cooks and academics. The most significant secular rituals of Terra Madre involve the theatrical celebration of its global character, beginning with the assembly of representatives from some 1600 ““food communities”” distributed throughout the world. Equally important are the many smaller scale activities in which the details of the movement's politics are articulated and embellished, at times in strikingly rhetorical ways. In this paper, which is based on ethnographic research, the theatrical and rhetorical qualities of Terra Madre as a political spectacle are explored in some detail. It is argued, in conclusion, that what is inadvertently exposed are some of the political myths which lie at the core of the Slow Food movement's contemporary philosophy.
Is the Phoenix Kosher??
Authors: weiss allen s.
Published: May 2008

The phoenix is the rarest of game birds, indeed so rare that its snob appeal by far supersedes that of all other luxury foods. As described by Ovid in his classic account, the Metamorphoses, this mythical creature spontaneously bursts into flame at maturity, to subsequently be reborn from its own ashes. The life cycle of the phoenix is thus the very allegory of cuisine, taken in its structural instance, as it spans the antithetical conditions of raw/cooked, cold/hot, fresh/rotten, dry/moist, aromatic/gamy. The phoenix would therefore be the perfect dish and the ideal offering, paradoxically encompassing the contradictory possibilities of diverse cooking techniques, inherent alimentary differences, and sacred symbolism. Like the trans substantiation of the host, or cannibalistic communion, the eating of the phoenix would constitute a truly transcendental gastronomic act. Given the phoenix's origin and its habitat in biblical lands, as well as its transcendental destiny, the question as to whether the bird is kosher is of the essence. Such an investigation will illuminate not only the symbolic structure of koshruth, but also the imaginary of gastronomy, untainted by prejudiced considerations of real cuisine.
Potato Agriculture, Late Blight Science, and the Molecularization of Plant Pathology
Authors: Turner R. Steven
Published: May 2008

By the mid-1980s nucleic-acid based methods were penetrating the farthest reaches of biological science, triggering rivalries among practitioners, altering relationships among subfields, and transforming the research front. This article delivers a "bottom up" analysis of that transformation at work in one important area of biological science, plant pathology, by tracing the "molecularization" of efforts to understand and control one notorious plant disease—the late blight of potatoes. It mobilizes the research literature of late blight science as a tool through which to trace the changing typography of the research front from 1983 to 2003. During these years molecularization intensified the traditional fragmentation of the late blight research community, even as it dramatically integrated study of the causal organism into broader areas of biology. In these decades the pathogen responsible for late blight, the oomycete Phytophthora infestans, was discovered to be undergoing massive, frightening, and still largely unexplained genetic diversification—a circumstance that lends the episode examined here an urgency that reinforces its historiographical significance as a casestudy in the molecularization of the biological sciences.
Use of thermal energy storage for sustainable buildings
Authors: Dincer I. , Rosen M. A.
Published: May 2008

Thermal energy storage (TES) systems are examined from the perspectives of energy, exergy, environmental impact, sustainability and economics, with a focus on how they can help make buildings more sustainable. Reductions in energy use and environmental emissions through TES are discussed in detail and highlighted with a case study. The case study demonstrates that TES exergy efficiencies normally are lower than energy efficiencies due to exergy destructions and losses. The importance of using exergy analysis to obtain more realistic and meaningful assessments than are obtained with energy analysis of the efficiency and performance of TES systems is demonstrated. The results indicate that TES can play a significant role in achieving more efficient, environmentally benign, sustainable and economic energy use in buildings, and appears to be an appropriate technology for addressing the mismatches that often occur between times of energy supply and demand.
Energy simulation of hybrid inter-city trains
Authors: Wen Q. , Kingsley S. , Smith R. A.
Published: May 2008

Reducing fuel consumption and environmental impacts are of particular importance to today's railway industry. Hybrid applications provide a relatively simple way to reduce the energy consumption of a vehicle. However, the effectiveness of this technology in railway applications is still largely unexplored, especially for inter-city railways, where duty cycles are often perceived less appropriate than other rail or road vehicle applications. Computer simulation techniques have been used to study and evaluate the potential of hybrid inter-city applications. The train-energy simulator (TrEN) at Imperial College London, is described. A prototype hybrid inter-city train that uses a battery as its energy storage device is studied. Several key parameters and configurations of this train, such as battery capacity, vehicle braking mode, controlalgorithm and energy management strategy, are investigated. The simulation study suggests that compared with a reference diesel—electric vehicle, the potential for fuel consumption reduction under optimised configurations that the hybrid inter-city train offers is significant.
Briefing: Steel construction and thermal bridging
Authors: Kendrick Chris
Published: May 2008

Thermal bridging has become more of an issue following the introduction of the 2006 revision part L of the Building Regulations for England and Wales. The term refers to the additional heat loss from a building as a result of either geometry (for example at corners) or components of relatively high thermal conductivity penetrating the insulated envelope (such as fixings and other structural elements). This heat flow must be added to the plane heat loss, accounted for in the U-value, to give a true measure of actual fabric heat loss.
A flowmeter for rectangular irrigation field channels
Authors: Goel A. , Narayana N. Pillai
Published: May 2008

The metering of small irrigation field channels is required for the efficient use and management of irrigation water. The weirs cause high loss of head and affect the sediment flow in the channel. The Pashall flumes of various sizes are not geometrically similar and they require calibration charts for each design. A simple flowmeter with straight boundaries with a contraction and a drop was tested in geometrically similar models of two sizes. It was found that when geometrically similar designs were made, a common design curve could be used to find the discharge under free and submerged conditions using measurements of head upstream and downstream of the meter.
A TEST OF REPRODUCTIVE POWER IN SNAKES
Authors: Boback Scott M. , Guyer Craig
Published: May 2008

Reproductive power is a contentious concept among ecologists, and the model has been criticized on theoretical and empirical grounds. Despite these criticisms, the model has successfully predicted the modal (optimal) size in three large taxonomic groups and the shape of the body size distribution in two of these groups. We tested the reproductive power model on snakes, a group that differs markedly in physiology, foraging ecology, and body shape from the endothermic groups upon which the model was derived. Using detailed field data from the published literature, snake‐specific constants associated with reproductive power were determined using allometric relationships of energy invested annually in egg production and population productivity. The resultant model accurately predicted the mode and left side of the size distribution for snakes but failed to predict the right side of that distribution. If the model correctly describes what is possible in snakes, observed size diversity is limited, especially in the largest size classes.