cssi/SciSciGPT-SciSciNet huggingface dataset:
Distribution of suspended sediment in a partially mixed estuary, Charleston Harbor, South Carolina, U.S.A.

A well-defined turbidity maximum zone (TMZ) exists 15–45 km upstream of the entrance to Charleston Harbor, South Carolina, on the Cooper River, where the salinity varies between 5–15 ppt. The TMZ is characterized by less than 60% light transmission over a 5 cm path-length near the bottom, as compared to 70–90% light transmission elsewhere. The TMZ oscillates along the Cooper River 3–13 km during a tidal cycle. The range of total suspended sediment (TSS) concentration is 40–100 mg l −1 in the TMZ, while 10–30 mg l −1 is the most common TSS concentration elsewhere in the estuarine portion of Charleston Harbor and the Cooper River. Transmissivity is well-correlated with TSS ( r 2 = 0·77) throughout the estuary. TSS concentration depends largely on tidal stage and varies significantly from spring to neap tide. Spring tide TSS concentrations are 2–3 times greater than concentrations during neap tides. The net downstream transport of suspended sediment is primarily a function of fresh water discharge, but is particularly large when flood events coincide with spring tides as was evident during the sampling of the TMZ following Hurricane Hugo (22 September 1989).
Formation of polymeric membranes by immersion precipitation: an improved algorithm for mass transfer calculations☆

Abstract This note describes an improved algorithm for the solution of the governing equations describing ternary mass transfer during the quench-period in the formation of immersion precipitation membranes. The algorithm is applied to the model developed by Reuvers et al. (J. Membr. Sci. 34 (1987) 45) for the water–acetone–cellulose acetate system. The improved algorithm developed in this work numerically simulates the multi component unsteady state diffusion process in immersion precipitation membrane formation without the necessity of user intervention in terms of initial guesses for the interfacial composition. Phase separation is assumed to take place at the spinodal. The algorithm is presented in detail for three component systems, however, it is easily extendable to four component systems. Numerical simulations using the improved algorithm are in good agreement with those of Reuvers et al. (J. Membr. Sci. 34 (1987) 45), however, experimental studies are required to validate some of the assumptions relating to the polymer phase separation.
The Tumor Microenvironment Controls Primary Effusion Lymphoma Growth in Vivo

Certain lymphomas in AIDS patients, such as primary effusion lymphoma (PEL), are closely associated with the lymphotropic γ herpes virus Kaposi’s sarcoma-associated herpes virus (KSHV), also called human herpesvirus 8. The virus is thought to be essential for tumorigenesis, yet systems to investigate PEL in vivo are rare. Here we describe PEL tumorigenesis in a new xenograft model. Embedded in Matrigel, PEL cells formed rapid, well-organized, and angiogenic tumors after s.c. implantation of C.B.17 SCID mice. Without Matrigel we did not observe comparable tumors, which implies that extracellular support and/or signaling aids PEL. All of the tumors maintained the KSHV genome, and the KSHV latent protein LANA/orf73 was uniformly expressed. However, the expression profile for key lytic mRNAs, as well as LANA-2/vIRF3, differed between tissue culture and sites of implantation. We did not observe a net effect of ganciclovir on PEL growth in culture or as xenograft. These findings underscore the importance of the microenvironment for PEL tumorigenesis and simplify the preclinical evaluation of potential anticancer agents.
Inverse photoemission as a probe for unoccupied electronic states

Abstract Inverse photoemission is shown to be complementary to photoemission in probing unoccupied electronic states. The momentum of delocalized valence states can be measured as well as their energy if low electron (photon) energies in the 10–40 eV range are used: Thus, energy band dispersions are obtained for bulk, surface, and adsorbate states which cannot be determined by other techniques. Applications are demonstrated for Si, GaAs, SiO 2 and metal-semiconductor interfaces.
Comparison of Thermal Hydraulic Simulations of Beyond Design Basis Events Using the MAAP4 and CENTS Computer Codes

The MAAP4 computer code (Reference 1) is often used to perform thermal hydraulic simulations of severe accident sequences for nuclear power plant Probabilistic Risk Assessments (PRAs). MAAP4 can be used to simulate accidents for both Boiling Water Reactors (BWRs) as well as Pressurized Water Reactors (PWRs). This assessment employs MAAP 4.0.6a for PWRs (References 1 and 5), which incorporates explicit thermal hydraulic modeling of the Reactor Coolant System (RCS) and Steam Generators (SGs), along with a nodalized integrated containment model. In the PRA environment, MAAP4 has been used for applications such as the development of PRA Level 1 and Level 2 success criteria and human action timings. The CENTS computer code (Reference 2) is a simulation tool that is typically used to analyze non-Loss of Coolant Accident (non-LOCA) events postulated to occur in nuclear power plants incorporating Combustion Engineering (CE) and Westinghouse Nuclear Steam Supply System (NSSS) designs. It is licensed by the NRC perform design basis non-LOCA safety analyses. It is a best estimate code which uses detailed thermal hydraulic modeling of the RCS and SGs; however, it does not model the containment performance. It is used to perform a wide spectrum of licensing and best estimate non-LOCA event analysis and has the capability to simulate operator actions. The CENTS models are the basis for several full scope simulators in the industry. The purpose of the analyses described in this paper is to compare MAAP4 and CENTS predictions for the Station Blackout (SBO) and Total Loss of Feedwater (TLOFW) scenarios for a representative PWR in the Westinghouse fleet that employs a CE NSSS design. The results of this comparison are used to highlight postulated MAAP4 user challenges and assist in developing guidance on selecting MAAP4 parameters for use in these scenarios. The results of the analyses presented in this paper indicate several useful insights. Overall, this paper shows that when care is taken to normalize the MAAP4 and CENTS primary side natural circulation flowrate and SG modeling, the trends of the MAAP4 and CENTS predictions of core uncovery agree reasonably well.© 2009 ASME
Acousto-Optic Joint Transform Correlator As Applied To Spread Spectrum Communications

A multichannel acousto-optic signal correlator based on optical joint transform correlation (OJTC) is presented. Parallel on-plane acousto-optic (AO) cells and a square law converter are used to produce cross-correlation of temporal-spatial signals. The AO cells are driven by frequency multiplexed temporal signals to produce spatially modulated signals. The joint Fourier transform of these spatially modulated signals is taken at the Fourier plane, where a square law detector converts the signals to a joint power spectra distribution. By simple coherent read-out, crosscorrelation of the input signals can be obtained at the output plane of the OJTC. Note that the proposed architecture can be packaged in a compact form. Since the multi-cell architecture can process broad band communication signals, we believe that the proposed technique can be applied to multi-frequency shift keying, as well as frequency hopped spread spectrum signals.
Capturing ambulatory activity decline in Parkinson's disease.

Background and Purpose: Relatively little is known about the natural evolution of physical activity–related participation restrictions associated with Parkinson’s disease (PD). We examined this issue prospectively, using continuous monitoring technology to capture the free-living ambulatory activity of persons with PD engaging in life situations. We specifically sought (1) to explore natural, long-term changes in daily ambulatory activity and (2) to compare the responsiveness of ambulatory activity parameters to clinical measures of gait and disease severity. Methods: Thirty-three persons with PD participated (Hoehn and Yahr range of 1–3). Participants wore a step activity monitor for up to 7 days at baseline and again at 1-year follow-up. Mean daily values were calculated for parameters indicative of amount, intensity, frequency, and duration of ambulatory activity. Clinical measures included the Unified Parkinson Disease Rating Scale, the 6-Minute Walk, and Maximal Gait Speed. Parametric tests for paired samples were used to investigate changes in ambulatory activity parameters and clinical measures. Results: Participants had significant declines in the amount and intensity of daily ambulatory activity but not in its frequency and duration (P < 0.007). Declines occurred in the absence of changes in clinical measures of gait or disease severity. The greatest 1-year decline occurred in the number of daily minutes participants spent engaging in at least moderate-intensity ambulatory activity. Conclusion: Continuous monitoring of ambulatory activity beyond mere step counts may serve as a distinct and important means of quantifying declining ambulatory behavior associated with disease progression or improved ambulatory behavior resulting from rehabilitation and medical and/or surgical interventions in persons with PD.
The god of the poor: Economics and religion in Latin America

The new political economy struggles to incorporate political processes into economic models. Religious institutions and commitments might similarly be incorporated into models of personal and social choice. This essay explores appropriate modeling strategies and suggests areas in which religion may prove relevant to the design of economic policy, particularly in Latin America. The paper concludes with points of discussion in a hypothetical dialogue between a North American economist and a Latin American theologian.
Virtualization aware job schedulers for checkpoint-restart

Application checkpoint and restart has been a widely studied problem over the last several decades. Despite immense volume of theory and several research project level implementations, there is very little by way of working solutions for the case of parallel distributed applications (such as MPI programs on a cluster). We describe our experiences in enhancing a job scheduler to leverage mechanisms of a virtual machine environment to support checkpoint-restart. We also describe the basic coordinated checkpoint-restart framework that we implemented on which this solution is based.
The new public personnel and the new public service

The New Public Administration sought a public service whose legitimacy would be based, in part, on its promotion of “social equity.” Since 1968, several personnel changes congruent with the New Public Administration have occurred: traditional managerial authority over public employees has been reduced through collective bargaining and changes in constitutional doctrines; the public service has become more socially representative; establishing a representative bureaucracy has become an important policy goal; more emphasis is now placed on employee participation in the work place; and legal changes regarding public administrators’ liability have promoted an “inner check” on their behavior. At the same time, however, broad systemic changes involving decentralization and the relationship between political officials and career civil servants have tended to undercut the impact of those changes in personnel. The theories of Minnowbrook I, therefore, have proven insufficient as a foundation for a new public servi...
The Tevatron Control System

The Tevatron Control System is a large distributed facility controlling the 6.28km Tevatron Accelerator from more than thirty distinct control locations. The system employs CAMAC hardware as the primary control interface. Self-cycling microprocessor based systems that utilize more suitable computer bus architectures are readily accommodated. The scale and nature of the Tevatron warrants special consideration as to system throughput and snapshot data handling. Computer based facilities can be provided at the service building level to assist host computer functions and to permit local diagnostics.
Localising People's Theatre in East Asia: performing Hakka women and pear-growers on Taiwan's fault line

Since the 1960s and 1970s, theatre artists from around the globe initiated a wave of theatre practice that is commonly known today as People's Theatre or Theatre for Empowerment. Transforming its participants from being mere ‘spectactors’ to ‘spect-actors’ capable of articulating their concerns on-stage, the ultimate goal of such theatre is to bring about social change to the daily reality of its practitioners. Beginning in the latter part of the twentieth century, People's Theatre has exerted a profound influence on the development of contemporary theatre in East Asia. First introduced to Taiwan in 1990, the methodologies of People's Theatre have been rapidly adapted by various socially conscientious and politically committed theatre groups. Taking the case of Shigang Mama Theatre Company (), this paper aims to examine the localisation of People's Theatre in the (post)colonial and post-martial context of Taiwan. Consisting of Hakka housewives and pear-growers, Shigang Mama Theatre Company was initially e...
Environmental pollution and impacts on soils and forests nutrition in North America

The effects of acid deposition, excess N deposition, and elevated CO2 on forest soils and nutrition in North America are reviewed. While there remains the possibility that acid deposition and excess N deposition are contributing to declines in red spruce, sugar maple, and southern pines, clearcut cause and effects are still not evident. Climate is clearly a major factor in red spruce decline in the northeastern U.S., but air pollution may contribute. There is some evidence that soil solution Al may be approaching deleterious levels in southeastern red spruce forests. Lack of proper management may be a major factor in the sugar maple and southern pine declines, but once again, air pollution as a potential contributor cannot be ignored. Nutrient budget analyses and discoveries of soils base cation depletion in certain sites suggest that base cation status is declining in forests of the southeastern U.S., but thus far, base cation deficiencies are uncommon. Recent research has revealed that there are more cases of N-saturated forests in North America than was previously suspected. These systems are characterized by high rates of soil N mineralization, high atmospheric N inputs, low uptakes, or some combination of these factors. Soil leaching and Al mobilization in such systems is often dominated by nitrate. However, the geographical extent of these types of systems is limited, and the traditional view that most forest ecosystems are N limited remains valid, especially where forest management is intensive. The limited information available on tree response to CO2. suggests N-deficient plants often grow faster with elevated CO2, whereas P-deficient plants often do not. Research is needed to 1) determine if the differences in response between N- and P-deficient plants is common, 2) the responses of plants deficient in other nutrients to elevated CO2, and 3) the interactions of CO2 increase, nutrient deficiencies, climate change.
Heterotrimeric G protein activation rapidly inhibits outgrowth of optic axons from adult and embryonic mouse, and goldfish retinal explants

Abstract Axons in the adult mammalian CNS normally do not regenerate following axotomy even though they retain the capacity for growth under certain experimental conditions. Although this implies that the regeneration of adult axons is under regulative control, very little is known about the signaling pathways responsible for this regulation. This study examines the possibility that a G protein signaling system exists in adult mouse optic fibers and that it functions to regulate axonal outgrowth. To induce the growth of optic fibers, retinas from adult mouse were placed in organotypic culture under serum free conditions and allowed to regenerate onto a laminin substrate. Heterotrimeric G proteins were stimulated by adding mastoparan (MST) to the medium while monitoring growing fibers with time lapse microscopy. Mastoparan treatment produced rapid growth cone collapse and axonal retraction which persisted while MST was present. Prior addition of pertussis toxin (PTX), which irreversibly inactivates the G proteins, G o and G i , completely blocked the effect of MST, confirming that MST was acting through the PTX sensitive G proteins. Selective activation of G proteins in the growth cone by local application of MST with a micropipet was equally effective. For comparison, equivalent experiments were performed on embryonic day 15 retinal explants and on retinal explants from adult goldfish, which normally regenerate in vivo. MST similarly inhibited these axons and this effect was blocked by PTX. However, embryonic fibers were less reliably affected compared to goldfish or adult mouse, suggesting a developmentally regulated sensitivity. The presence of G-proteins in the mouse axons was further tested immunohistochemically using antibodies against. G o /G i . Positive staining was detected in the growth cones and shaft of adult and embryonic mouse optic fibers. These findings demonstrate that G protein activation inhibits axonal outgrowth and suggest that there may be a G protein signaling pathway that normally regulates this outgrowth. However, since this pathway appears to exist in both axons that can regenerate and those that normally do not, the presence of PTX-sensitive G proteins alone cannot account for regenerative failure. Regenerative failure may instead be explained as the selective or increased activation of this pathway in the adult mammalian CNS.
A generalized method for one-way coupling of CTH and Lagrangian finite element codes with complex structures using the interdisciplinary computing environment

In the past, CTH (a finite volume, shock physics code) has been coupled with different Lagrangian finite element codes like ProntoSD and LS-Dyna, to solve blast-structure interaction problems. In many situations, a two-way coupling of these codes is unnecessary. Specifically, when the deformation of the structure has little impact on the developing blast, a one-way coupling is sufficient. Unfortunately, when the structure is complex, and particularly when the model contains shell elements, accurately generating the load curves for the finite element input can be difficult. A generalized method for generating the necessary load curves for the finite element input from CTH has been developed at ARL by using the Interdisciplinary Computing Environment (ICE). While others have successfully coupled CTH with finite element codes in the past, this method accurately represents the finite elements model's geometry on the Eulerian mesh and can be applied to any code with a pressure vs. time element loading capacity. An accurate representation of the finite element model is inserted into the CTH mesh even if the model contains shell elements. Using this method, an example problem of a land mine interacting with a complex vehicle structure is presented.
A prospective study of reproductive factors and risk of epithelial ovarian cancer

Background. Parity and long term use of oral contraceptives have been associated consistently with a decreased risk of ovarian cancer. However, previous reports of the relationship of other reproductive factors (time since first use or last use of oral contraceptives, age at menarche or menopause, age at first birth) with overian cancer have been inconsistent. Methods. The authors studied these relationships in the Nurses' Health Study, a prospective cohort study of 121,700 female registered nurses aged 30–55 years in 1976 when the study began. From 1976 to 1988, 260 cases of confirmed epithelial overaian cancer occurred among 1.2 million person-years of follow-up. Results. A Statistically significant inverse association was observed between parity and overian cancer risk (relative risk [RR] = 0.84; 95% confidence interval [CI]=0.77–0.91 per pregnancy); age at first birth was not associated independently with risk. In age-adjusted analyses, a significant inverse association was noted between long term use of oral contraceptives and ovarian cancer, which was no longer significant after controlling for other ovarian cancer risk factors (RR with ≥5 years' use: 0.65; 95% CI = 0.40–1.05). After control for duration of use, a weak nonsignificant inverse associated was observed with time since first oral contraceptive use and no independent effect of time since last use. Neither age at menarche nor age at menopause use associated significantly with ovarian cancer risk. Conclusions. In this large prospective study, parity was the only reproductive factor that had a substantial independent associated with ovarian cancer. Long term oral contraceptive use also appeared to have an inverse relationship with ovarian cancer, although this association was of borderline significance (P = 0.11) after adjustment for other risk factors. Cancer 1995; 76:284–90.
GDR: a system for guided data repair

Improving data quality is a time-consuming, labor-intensive and often domain specific operation. Existing data repair approaches are either fully automated or not efficient in interactively involving the users. We present a demo of GDR, a Guided Data Repair system that uses a novel approach to efficiently involve the user alongside automatic data repair techniques to reach better data quality as quickly as possible. Specifically, GDR generates data repairs and acquire feedback on them that would be most beneficial in improving the data quality. GDR quantifies the data quality benefit of generated repairs by combining mechanisms from decision theory and active learning. Based on these benefit scores, groups of repairs are ranked and displayed to the user. User feedback is used to train a machine learning component to eventually replace the user in deciding on the validity of a suggested repair. We describe how the generated repairs are ranked and displayed to the user in a "useful-looking" way and demonstrate how data quality can be effectively improved with minimal feedback from the user.
Multi-band multi-service sensing: metamaterials myth and reality

Demands by the communications industry for greater bandwidth push the capability of conventional wireless technology. Part of the Radio Spectrum that is suitable for mobility is very limited. Higher frequency waves above 30 GHz tend to travel only a few miles or less and generally do not penetrate solid materials very well. Unmanned Aerial System applications require electronic scanning antenna capabilities, in challenging environmental conditions, over very large bandwidths. In addition to that, it is desirable to have as much reduction as possible in size, weight, power and cost. Metamaterials are recently being introduced by periodic repetition of some inclusions in a host medium, which may be described as effective media characterized by a set of equivalent constitutive parameters. Self-similarity in creating periodic structures is the basis of building volume or 2D holographic components. The latter does more than periodic repeats. Similar, but more advanced concepts (fractal in nature) are used to model phase screens used in modeling the atmospheric turbulence. Unfortunately, metamaterials (MTMs) are anisotropic (direction-dependent) and this makes their application limited in terms of use as antennas for mobile platforms. However, conceptually, controlled-anisotropy can be applied to make phased-arrays, beam-forming, and beam scanning. This issue then begs the question of cost comparison with conventional materials that can be found in nature, e.g., low-cost optics lenses, or conventional RF scanning antennas. As for lensing and fixed platform imaging, the story is very different, as super-lens is expected to be a byproduct. Nevertheless, even if metamaterials become readily available, the atmosphere around the globe cannot be replaced. Neither, broadband wireless connectivity to a mobile can be achieved via fiber optics. This paper, presents a Hybrid radio-frequency (RF) and Wireless Optical solution to provide adaptive sensing in an opportunistic fashion, with or without metamaterials. A byproduct of the latter will be broadband and reliable global connectivity.
A test of the binaural equal-loudness-ratio hypothesis for tones.

It is well known that a tone presented binaurally is louder than the same tone presented monaurally. It is less clear how this loudness ratio changes as a function of level. The present experiment was designed to directly test the Binaural Equal-Loudness-Ratio hypothesis (BELRH), which states that the loudness ratio between equal-SPL monaural and binaural tones is independent of SPL. If true, the BELRH implies that monaural and binaural loudness functions are parallel when plotted on a log scale. Cross-modality matches between string length and loudness were used to directly measure binaural and monaural loudness functions for nine normal listeners. Stimuli were 1-kHz 200-ms tones ranging in level from 5 dB SL to 100dB SPL. A two-way ANOVA showed significant effects of level and mode (binaural or monaural) on loudness, but no interaction between the level and mode. Consequently, no significant variations were found in the binaural-to-monaural loudness ratio across the range of levels tested. This finding ...
Incomplete Mechanisms and Efficient Allocation in Labour Markets

Efficiency is analyzed in a Walrasian model of labour markets with adverse selection. Workers are distinguished by productivity and preferences; firms are distinguished by productivity and ability to distinguish workers. An equilibrium is defined to be constrained efficient if it cannot be dominated by an incomplete mechanism (IM). The set of equilibria turns out to have an interesting structure. Within the class of strongly monotonic economies, there exists at least one efficient equilibrium. Under slightly stronger conditions, an equilibrium is dominated by an IM only if it can be dominated by another equilibrium, that is, equilibria are Pareto-ranked.
Posttraumatic stress disorder and pregnancy complications

Abstract Objective: To assess the associations between specific pregnancy complications and posttraumatic stress disorder based on neurobiologic and behavioral characteristics, using Michigan Medicaid claims data from 1994–1996. Methods: Two thousand, two hundred nineteen female recipients of Michigan Medicaid who were of childbearing age had posttraumatic stress disorder on the basis of International Classification of Diseases, 9th Revision (ICD-9) codes. Twenty percent (n = 455) of those recipients and 30% of randomly selected comparison women with no mental health diagnostic codes (n = 638; P Results: After controlling for demographic and psychosocial factors, women with posttraumatic stress disorder had higher odds ratios (ORs) for ectopic pregnancy (OR 1.7, 95% confidence interval [CI] 1.1, 2.8), spontaneous abortion (OR 1.9, 95% CI 1.3, 2.9), hyperemesis (OR 3.9, 95% CI 2.0, 7.4), preterm contractions (OR 1.4, 95% CI 1.1, 1.9), and excessive fetal growth (OR 1.5, 95% CI 1.0, 2.2). Hypothesized labor differences were not confirmed and no differences were found for complications not thought to be related to traumatic stress. Conclusions: Pregnant women with posttraumatic stress disorder might be at higher risk for certain conditions, and assessment and treatment for undiagnosed posttraumatic stress might be warranted for women with those obstetric complications. Prospective studies are needed to confirm present findings and to determine potential biologic mechanisms. Treatment of traumatic stress symptoms might improve pregnancy morbidity and maternal mental health.
Bribery: Not Only Wrong, But Costly Too?

This article discusses bribery, its ethical implications, and how certain parts of the world consider it a necessary tool for doing business. While most concerns about bribery encompass its ethical ramifications, many experts wonder if it comes with economic consequences and costs. A study tackled the question of whether a company's willingness to use bribery in business affected its economic growth. Additional factors to consider when employing bribery as a business tactic are the degree of the consequences exerted by the payments, as well as government authorized taxation on a firm's economic growth.
A Method for Improving Component Decoupling Using Advanced Capacitor Under Ball Grid Array (ACUB)

Industry demands on power delivery continue to increase with higher performance silicon products. As a result, higher current sustainability and better transient response are key parameters frequently sought in successful power delivery designs. One key design feature for improved transient response involves locating decoupling capacitance as close to the load as possible. At the board level, this is typically accomplished by placing capacitors around the immediate vicinity of the load. With a set of identical capacitors in parallel, total capacitance is essentially a multiple of the number of caps while the effective series resistance and inductance is divided. However the realities of package and motherboard design can often limit the number and size of the capacitors placed in the vicinity of the load. In some cases, the capacitors may interfere with other routings to and from the component. In other cases, placement of the capacitors with respect to the DC current path may limit their effectiveness by inducing a large effective series inductance to the load. This paper describes a potential design method for maximizing capacitor effectiveness while minimizing its impact on other board features. The design is primarily implemented in board assembly and involves placing capacitors directly between power and ground board-component solder joints. As an extension of Capacitor Under BGA designs, this method is termed Advanced Capacitor Under BGA (ACUB). Using ACUB can improve load decoupling, but can require new approaches to board and component assembly. This paper discusses a number of potential design improvements allowed for using this design approach. In addition, factors involved in successful assembly are discussed and sets of proof-of-concept prototype designs are presented along with assembly results. From this, some designs with potential for further development are identified and next steps discussed.Copyright © 2003 by ASME
Macropolygon morphology, development, and classification on North Panamint and Eureka playas, Death Valley National Park CA

Abstract Panamint and Eureka playas, both located within Death Valley National Park, exhibit a host of surficial features including fissures, pits, mounds, and plant-covered ridges, representing topographic highs and lows that vary up to 2 m of relief from the playa surface. Aerial photographs reveal that these linear strands often converge to form polygons, ranging in length from several meters to nearly a kilometer. These features stand out in generally dark contrast to the brighter intervening expanse of flat, plant-free, desiccated mud of the typical playa surface. Ground-truth mapping of playa features with differential GPS (Global Positioning System) was conducted in 1999 (North Panamint Valley) and 2002 (Eureka Valley). High-resolution digital maps reveal that both playas possess macropolygons of similar scale and geometry, and that fissures may be categorized into one of two genetic groups: (1) shore-parallel or playa-interior desiccation and shrinkage; and (2) tectonic-induced cracks. Early investigations of these features in Eureka Valley concluded that their origin may have been related to agricultural activity by paleo-Indian communities. Although human artifacts are abundant at each locale, there is no evidence to support the inference that surface features reported on Eureka Playa are anthropogenic in origin. Our assumptions into the genesis of polygons on playas is based on our fortuitous experience of witnessing a fissure in the process of formation on Panamint Playa after a flash flood (May 1999); our observations revealed a paradox that saturation of the upper playa crusts contributes to the establishment of some desiccation features. Follow-up visits to the same feature over 2 yrs' time are a foundation for insight into the evolution and possible longevity of these features.
Oncogenic K-Ras and Loss of Smad4 Mediate Invasion by Activating an EGFR/NF-κB Axis That Induces Expression of MMP9 and uPA in Human Pancreas Progenitor Cells

Activating K-Ras mutations and inactivating mutations of Smad4 are two common genetic alterations that occur in the development and progression of pancreatic ductal adenocarcinomas (PDAC). To further study the individual and combinatorial roles of these two mutations in the pathogenesis of PDAC, immortalized human pancreas nestin postive cells (HPNE) were genetically modified by either expressing oncogenic K-Ras (HPNE/K-Ras), by shRNA knock down of Smad4 (HPNE/ShSmad4) or by creating both alterations in the same cell line (HPNE/K-Ras/ShSmad4). We previously found that expression of oncogenic K-Ras caused an increase in expression of EGFR and loss of Smad4 further enhanced the up regulation in expression of EGFR and that this increase in EGFR was sufficient to induce invasion. Here we further investigated the mechanism that links mutational alterations and EGFR expression with invasion. The increase in EGFR signaling was associated with up regulation of MMP9 and uPA protein and activity. Moreover, the increase in EGFR signaling promoted a nuclear translocation and binding of RelA (p65), a subunit of NF-κB, to the promoters of both MMP-9 and uPA. Treatment of HPNE/K-Ras/ShSmad4 cells with an inhibitor of EGFR reduced EGF-mediated NF-κB nuclear translocation and inhibitors of either EGFR or NF-κB reduced the increase in MMP-9 or uPA expression. In conclusion, this study provides the mechanism of how a combination of oncogenic K-Ras and loss of Smad4 causes invasion and provides the basis for new strategies to inhibit metastases.
NATURAL FREQUENCY VEERING IN PLANETARY GEARS

To achieve noise and vibration reduction in planetary gear applications, key design parameters are often varied to avoid resonances, optimize load distribution, and reduce weight. In the plots of natural frequencies versus planetary gear parameters, veering phenomena occur when two eigenvalue loci approach each other, but then abruptly veer away. The importance of veering is manifested in the dramatic changes in the vibration modes of the veering natural frequencies and the consequent impact on response. This work analytically characterizes the rules of eigenvalue veering in planetary gears. The coupling factors between two close eigenvalue loci are approximated by perturbation analysis. Special veering patterns were obtained using the unique properties of planetary gear vibration modes. The results are illustrated by an example. Key design parameters were investigated, and generalized guidance is provided for tuning planetary gear natural frequencies. *Communicated by S. Sinha.
Assessment of dilation methods in achalasia: large diameter mercury bougienage followed by pneumatic dilation as needed

In a retrospective study, 33 achalasia patients were treated with dilation therapy using large diameter mercury bougienage (mean, 56 French) and/or pneumatic balloon dilation. Mean follow-up time was 35 months. Mercury bougienage, performed in 20 patients, was successful in 10 (50%) with no complications. Pneumatic dilation was performed as initial therapy or in those having failed previous pharmacologic therapy and/or bougienage. A successful response was achieved in 19 of 23 patients (83%), with a 3.2% complication rate. In addition, in four patients with eventual recurrence of symptoms after initial pneumatic dilation, bougienage was used as a successful alternative to repeat pneumatic treatment. The combined efficacy of both forms of dilation was 88% with a complication rate of 1.4%. These data indicate that mercury bougienage should be considered initial therapy for achalasia in view of its simplicity, safety, and acceptable efficacy, followed by pneumatic dilation if bougienage is unsuccessful. Bougienage also may be considered if eventual recurrent symptoms develop after initially successful pneumatic dilation. Surgery should be utilized only if dilation therapy fails to achieve a satisfactory response.
Intensity-modulated tangential beam irradiation of the intact breast

Abstract Purpose: To evaluate the potential benefits of intensity modulated tangential beams in the irradiation of the intact breast. Methods and Materials: Three-dimensional treatment planning was performed on five left and five right breasts using standard wedged and intensity modulated (IM) tangential beams. Optimal beam parameters were chosen using beams-eye-view display. For the standard plans, the optimal wedge angles were chosen based on dose distributions in the central plane calculated without inhomogeneity corrections, according to our standard protocol. Intensity-modulated plans were generated using an inverse planning algorithm and a standard set of target and critical structure optimization criteria. Plans were compared using multiple dose distributions and dose volume histograms for the planning target volume (PTV), ipsilateral lung, coronary arteries, and contralateral breast. Results: Significant improvements in the doses to critical structures were achieved using intensity modulation. Compared with a standard-wedged plan prescribed to 46 Gy, the dose from the IM plan encompassing 20% of the coronary artery region decreased by 25% (from 36 to 27 Gy) for patients treated to the left breast; the mean dose to the contralateral breast decreased by 42% (from 1.2 to 0.7 Gy); the ipsilateral lung volume receiving more than 46 Gy decreased by 30% (from 10% to 7%); the volume of surrounding soft tissue receiving more than 46 Gy decreased by 31% (from 48% to 33%). Dose homogeneity within the target volume improved greatest in the superior and inferior regions of the breast (approximately 8%), although some decrease in the medial and lateral high-dose regions (approximately 4%) was also observed. Conclusion: Intensity modulation with a standard tangential beam arrangement significantly reduces the dose to the coronary arteries, ipsilateral lung, contralateral breast, and surrounding soft tissues. Improvements in dose homogeneity throughout the target volume can also be achieved, particularly in the superior and inferior regions of the breast. It remains to be seen whether the dosimetric improvements achievable with IMRT will lead to significant clinical outcome improvements.
Possible tests of anomalously large leptonic weak interactions in high-energy e+ e- collisions

Some consequences of two possible mechanisms of a breakdown in $V\ensuremath{-}A$ theory leading to anomalously large weak vertices in hitherto untested leptonic reactions are discussed. We consider the processes ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ and ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\nu}}_{e}{\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\nu}}}_{e}\ensuremath{\gamma}$ with total c.m. energies around 10 GeV. A purely leptonic neutral current can cause a measurable forward-backward muon asymmetry and a muon polarization in the first reaction. Expressions are computed for these effects in terms of the most general nonderivative coupling. On the other hand, some intrinsic anomaly in diagonal weak vertices can make the cross section for the second process large and measurable; in that case, study of the $\ensuremath{\gamma}$ spectrum can reveal information about the structure of such an anomalous vertex. The angular distribution and the energy spectrum of the photon are computed for the $V\ensuremath{-}A$ and $S\ensuremath{-}P$ theories up to terms that are first order in ${(\mathrm{total}\mathrm{c}.\mathrm{m}.\mathrm{energy})}^{2}$/2 ${(\mathrm{i}\mathrm{n}\mathrm{t}\mathrm{e}\mathrm{r}\mathrm{m}\mathrm{e}\mathrm{d}\mathrm{i}\mathrm{a}\mathrm{t}\mathrm{e}\ensuremath{-}\mathrm{b}\mathrm{o}\mathrm{s}\mathrm{o}\mathrm{n}\phantom{\rule{0ex}{0ex}}\mathrm{m}\mathrm{a}\mathrm{s}\mathrm{s})}^{2}$.
Chronic Stimulation–Induced Changes in the Rodent Thyroarytenoid Muscle

Purpose Therapies for certain voice disorders purport principles of skeletal muscle rehabilitation to increase muscle mass, strength, and endurance. However, applicability of limb muscle rehabilitation to the laryngeal muscles has not been tested. In this study, the authors examined the feasibility of the rat thyroarytenoid muscle to remodel as a consequence of increased activity instantiated through chronic electrical stimulation. Method Twenty adult Sprague-Dawley rats (Rattus norvegicus), assigned to a 1-week or 2-week stimulation group, were implanted with a nerve cuff electrode placed around the right recurrent laryngeal nerve and were fitted with a head connector. All animals were placed under anesthesia twice a day for 1 hr each time. Following the training, rats were killed, and thyroarytenoid muscles were isolated for histology and immunohistochemistry. Results Mean muscle fiber area decreased, neuromuscular junction density increased, mitochondrial content increased qualitatively, and glycogen-p...
The ameloblastomatous potentiality of odontogenic epithelium demonstrated in tissue culture.

Abstract Histologically, the ameloblastoma may show all of the structures normally seen in odontogenic epithelium, but a single biopsy specimen illustrates only a given static phase in the process of neoplasia. Tissue culture studies of rat embryo tooth buds demonstrated epithelial proliferation from the borders of odontogenic epithelium and the formation of lamellar-like structure observed in ameloblastomas. Later, the tooth buds grown in vitro showed formation of stellate reticulum-like structure in the epithelial outgrowths and formation of microcysts characteristic of ameloblastomas. Dissected epithelial outgrowths recultivated in vitro showed similar changes. These studies offer additional experimental evidence that ameloblastomas originate from epithelium with odontogenic potentiality.
Notes from the cancer underground: health attitudes and practices of participants in the laetrile movement.

In an earlier paper in this journal we presented data on the social characteristics of participants in the Laetrile movement [1]. In this note we present data on the health attitudes and practices of these people. A description of the symposium at which the data were collected and details of the methodological procedures are contained in the earlier paper. It should be emphasized that the data should be viewed as exploratory. Completed questionnaires were obtained from 252 people. Virtually all were white, most were female (60%), middle-aged (the mean age was 44 years), highly educated (61% had some college experience and 15% had done post-graduate work), and rural or from small towns (65%). A number of the items on health attitudes and practices were taken from the National Health Survey, thus allowing comparisons with national norms.
A review of motivational models for improving hand hygiene among an increasingly diverse food service workforce

Abstract Poor hand hygiene is a leading cause for the spread of foodborne illnesses in the foodservice industry. A series of complex motivational interventions must be employed to permanently change the behavior of workers, to increase their compliance and sustain appropriate levels of proper hand hygiene. Unlike the healthcare industry, which uses large, costly multi-modal behavior modification strategies, the foodservice industry must deploy rapid, cost-efficient strategies that take into account a high employee turnover rate and diverse demographics. This paper reviews the current motivational models used in the foodservice industry and examines the habitual nature of complying with good hand hygiene. It also reviews current techniques to increase hand hygiene compliance using clues from three of the five basic senses (sight, hearing, and smell) and two mechanisms (context-bridging and disgust). Lastly, the current model for habit intervention is evaluated, and its possible applications in the foodservice industry with additional reminders are accessed. We believe that this review will provide foodservice managers the background, theoretical basis and practical applications for making long-term changes in their employees on this and similar critical behaviors in foodservice.
On the Measurement of Teacher Effectiveness

A teacher's effectiveness in the first economics course influences student performance in the subsequent course. The author tested this carry-over effect in the standard two-course economics sequence.
In Situ Particle Size Reduction of Alfalfa and Timothy Hay as Influenced by Form and Particle Size

Abstract Our objectives were to characterize particle size reduction of alfalfa and timothy hay by in situ incubation. Alfalfa and timothy hay were chopped at .64-cm theoretical length of cut. Subsamples were dry sieved through a 3.2-mm screen, yielding particles > 3.2 and 3.2 and 3.2 mm exhibited linear, whereas chopped and sieved 1.18 mm accounted for 63.0 to 98.4% of the initial DM, which was reduced to 14.9 to 24.1% by 100 h. Microbial fermentation and detrition associated with ruminal movements appear to contribute substantially to particle breakdown.
Postzygotic isolation involves strong mitochondrial and sex-specific effects in Tigriopus californicus, a species lacking heteromorphic sex chromosomes.

Detailed studies of the genetics of speciation have focused on a few model systems, particularly Drosophila. The copepod Tigriopus californicus offers an alternative that differs from standard animal models in that it lacks heteromorphic chromosomes (instead, sex determination is polygenic) and has reduced opportunities for sexual conflict, because females mate only once. Quantitative trait loci (QTL) mapping was conducted on reciprocal F2 hybrids between two strongly differentiated populations, using a saturated linkage map spanning all 12 autosomes and the mitochondrion. By comparing sexes, a possible sex ratio distorter was found but no sex chromosomes. Although studies of standard models often find an excess of hybrid male sterility factors, we found no QTL for sterility and multiple QTL for hybrid viability (indicated by non-Mendelian adult ratios) and other characters. Viability problems were found to be stronger in males, but the usual explanations for weaker hybrid males (sex chromosomes, sensitivity of spermatogenesis, sexual selection) cannot fully account for these male viability problems. Instead, higher metabolic rates may amplify deleterious effects in males. Although many studies of standard speciation models find the strongest genetic incompatibilities to be nuclear–nuclear (specifically X chromosome–autosome), we found the strongest deleterious interaction in this system was mito–nuclear. Consistent with the snowball theory of incompatibility accumulation, we found that trigenic interactions in this highly divergent cross were substantially more frequent (>6 × ) than digenic interactions. This alternative system thus allows important comparisons to studies of the genetics of reproductive isolation in more standard model systems.
Reruns 2.0: Revising Repetition for Multiplatform Television Distribution

Abstract This article explores the opportunities and problems thus far presented by the movement of old TV shows into new online platforms. Media users can easily view, remix, and share old television content, and media industries struggle to adapt their old business models to these new modes of communication.
Proteins and biomembranes under pressure: biomedical aspects

Abstract Two examples of our biomedical research with high pressure infrared spectroscopy are given to demonstate that the pressure parameter is a powerful tool for investigation of biomedical problems.