cssi/SciSciGPT-SciSciNet huggingface dataset:
Supersymmetric Pati-Salam Models from Intersecting D6-branes: A Road to the Standard Model

Abstract We provide a systematic construction of three-family N = 1 supersymmetric Pati–Salam models from Type IIA orientifolds on T 6 / ( Z 2 × Z 2 ) with intersecting D6-branes. All the gauge symmetry factors SU ( 4 ) C × SU ( 2 ) L × SU ( 2 ) R arise from the stacks of D6-branes with U ( n ) gauge symmetries, while the “hidden sector” is specified by USp ( n ) branes, parallel with the orientifold planes or their Z 2 images. The Pati–Salam gauge symmetry can be broken down to the SU ( 3 ) C × SU ( 2 ) L × U ( 1 ) B − L × U ( 1 ) I 3 R via D6-brane splittings, and further down to the Standard Model via D- and F-flatness preserving Higgs mechanism from massless open string states in a N = 2 subsector. The models also possess at least two confining hidden gauge sectors, where gaugino condensation can in turn trigger supersymmetry breaking and (some) moduli stabilization. The systematic search yields 11 inequivalent models: 8 models with less than 9 Standard Model Higgs doublet-pairs and 1 model with only 2 Standard Model Higgs doublet-pairs, 2 models possess at the string scale the gauge coupling unification of SU ( 2 ) L and SU ( 2 ) R , and all the models possess additional exotic matters. We also make preliminary comments on phenomenological implications of these models.
Treatment uniformity of plasma immersion ion implantation studied with three-dimensional model systems

Abstract Plasma immersion ion implantation is a rapidly developing technique for ion-beam treatment of materials, mainly metals and semiconductors. This technique was developed initially to circumvent the line-of-sight restrictions of conventional beam-line ion implantation. In contrast to the latter, the treatment of three-dimensional samples does not require complicated manipulation of the workpiece and ion beam. With this concept, knowledge of treatment homogeneity is of particular importance for the further development of plasma immersion ion implantation. In the present paper, homogeneity measurements of model systems are discussed. Silicon wafer segments mounted on wedge-shaped and V-shaped sample holders with different edge angles (30° to 120°), and on a U-shaped sample holder (trench), were treated by plasma immersion ion implantation with argon ions of −45 kV high-voltage pulses. The samples were analysed for lateral implantation concentration by Rutherford backscattering spectrometry measurements. The results show that, for wedge-shaped samples, gradients in concentration of implanted argon by a factor of up to six develop, depending on the process parameters. In the case of trenches, differences of more than an order of magnitude between the implantation concentrations of the side walls and bottom of the trench were found.
Poly (A)·oligo (dT)‐stimulated DNA polymerase activity in preimplantation mouse embryos

DNA polymerase activity with Poly (A) . oligo(dT) as a template-primer has been found in preimplantation mouse embryos. A sharp increase in enzyme activity was observed at the time of formation of inner cell mass (ICM) and trophoblast cells. Differential inhibition of enzyme activity before and after ICM formation raised the possibility that more than one Poly(A) . oligo(dT)-directed DNA polymerase was detected.
Load induction of cardiac hypertrophy

We have shown in surgical animal models that increased and decreased cardiac loading results in myocardial hypertrophy and atrophy, respectively. These changes, which are readily reversible upon the restoration of a normal cardiac load, occur without any requirement for neural or circulating intermediary factors. In our current studies we have focused first on an unequivocal demonstration of these same phenomena in a much simpler model consisting of isolated quiescent cardiocytes maintained in serum-free medium and second on an elucidation in isolated papillary muscles of the means by which a change in cardiac load is transduced into a change in cardiac mass. Adherent isolated adult cardiocytes held at their rest length exhibit only a very gradual loss of their differentiated features. In contrast, unloaded cardiocytes in suspension culture immediately cease nuclear RNA synthesis and rapidly come to resemble unloaded cardiac muscle--a cardiocyte cellular analog of cardiac tissue atrophy, while loaded adherent cardiocytes stretched past their rest length respond in terms of synthetic activity characteristic of growth initiation--a cardiocyte cellular analog of cardiac tissue hypertrophy. Both quiescent and contracting papillary muscles exhibit increased synthesis of cardiocyte structural proteins in direct relation to active and/or passive muscle tension. This load-dependent protein synthesis appears to require initial sodium influx through deformation-dependent sarcolemmal cation channels, in a manner analogous to the dependence of mitogen-stimulated growth initiation in a variety of other cell types on initial sodium entry, albeit by a different mechanism. Thus, load variation functions as an independent regulator of cardiac growth in the adult, and sarcolemmal deformation with consequent sodium entry may be an initial direct link between load and growth in the heart.
TU-EE-A3-04: Registration of On-Board Digital Tomosynthesis and Planning CT for Partial Breast Irraadiation Patient Setup Verification with Surgical Clips

Purpose: This study examines the accuracy of On‐Board Digital Tomosynthesis (OB‐DTS) imaging by the localization of individual surgical clips and registration to planning CT instead of a reference‐DTS (RDTS). Using planning CT instead of a RDTS for registration might decrease the uncertainty of the registration resulting from the added edge blurring of DTS and simplify the setup verification process. Method and Materials: A solid water breast phantom containing four surgical clips was imaged with CT and OB‐DTS modalities. The OB‐DTS was acquired for a 40° lateral angle (kV source: 250°–290°). An open‐source GPU based FDK filtered backprojection algorithm was used for reconstruction of DTS image sets. The centroids of all the clips were localized in the DTS image sets and locations were compared with the clip locations in CTimage sets. Using a filtered cross‐correlation algorithm, the OB‐DTS was registered with the CT and RDTS image sets and the registration accuracy of OB‐DTS was calculated. Results: Clip centroids were found to be within 1 mm in DTS and CTimage sets. The OB‐DTS was registered with the CT within 1 mm ± 2 mm along the x‐axis (direction of projection) and less than 1 mm ± 1 mm along the two orthogonal (y and z) axes with a maximum translation of ±1.4 cm in the orthogonal axes and ±4.7 cm along the x‐axis. The OB‐DTS was registered with the RDTS within 4 mm ± 11.5 mm along the x‐axis, 1.4 mm ± 2.8 mm along the y‐axis and 0.5 mm ± 0.7 mm along the z‐axis, with a maximum translation of ±1.4 cm in the orthogonal axes and ±2.8 cm along the axis of propagation. Conclusion: OB‐DTS can be registered to CT with equal or better accuracy than when registered with RDTS and with greater translations along the propagation axis.
The formation and some reactions of η-phenyllithiumtricarbonylchromium☆

A transmetalation reaction between bis(η6-phenyltricarbonylchromium)mercury and n-butyllithium has afforded (η6-phenyllithium)tricarbonylchromium in moderate yield. This novel organolithium reagent has been characterized by methanolysis, carbonation, and by reactions with (CH3)3SiCl and acetyl chloride. Reactions of (η6-phenyllithium)tricarbonylchromium with pyridine, (C6H5)2PCl, and C6H5PCl2 have afforded the corresponding pyridyl- and phosphinobenzenetricarbonylchromium complexes, respectively. A reaction with PCl3 produced bis(η6-phenyltricarbonylchromium)-n-butylphosphine as the only identifiable product.
Autologous Blood Transfusion: Evaluation of an Alternative Strategy in Reducing Exposure to Allogeneic Blood Transfusion

The perceived risk of transfusion-transmitted disease led to the rejuvenation of autologous blood transfusion (ABT). ABT, a process in which the blood donor and recipient are the same, is increasingly becoming an integral component of the elective surgical protocol in many institutions. Various methods of ABT are being utilized. These include: preoperative blood donation, in which the patient donates blood prior to surgery and the blood is stored for an expected need during or after surgery; acute normovolemic hemodilution, in which blood is collected immediately prior to surgery and replaced with cell free fluids and then returned to the patient upon need; intraoperative blood salvage in which blood is collected from the surgical field and is reinfused after being washed and finally, postoperative blood salvage in which collected shed blood from surgical drains is reinfused to the patient. Although ABT is known to reduce the risk of allogeneic blood transfusion, it is not risk free and should be evaluate...
An Experimental Examination of Factors Affecting Click-Through of Keyword Search Ads

This study examines potential determinants of online users’ click-through behaviors for keyword search ads within the theoretical frameworks of dual processing models and the persuasion knowledge model. In total, 182 undergraduate students participated in an experiment featuring a mixed factorial design with two between-subject factors (i.e., perceived fit and rank of ad) and one within-subject factor (i.e., product involvement). Additionally, the level of persuasion knowledge was measured. The study found positive effects of perceived fit of an ad with a search term, the rank of ad in a search results page, and the level of product involvement on the target ad click-through rates. A negative effect of persuasion knowledge about keyword search ads was found for click-through rates. Furthermore, the study found that (1) the level of product involvement moderated the effects of perceived ad's fit on click-through and (2) the level of persuasion knowledge moderated the effects of the rank of an ad. The resul...
Enzymatic and Cellular Characterization of a Catalytic Fragment of CTP:Phosphocholine Cytidylyltransferase α *

To probe the mechanism of lipid activation of CTP:phosphocholine cytidylyltransferase (CCTα), we have characterized a catalytic fragment of the enzyme that lacks the membrane-binding segment. The kinetic properties of the purified fragment, CCTα236, were characterized, as well as the effects of expressing the fragment in cultured cells. CCTα236 was truncated after residue 236, which corresponds to the end of the highly conserved catalytic domain. The activity of purified CCTα236 was independent of lipids and about 50-fold higher than the activity of wild-type CCTα assayed in the absence of lipids, supporting a model in which the membrane-binding segment functions as an inhibitor of the catalytic domain. Thek cat/K m values for CCTα236 were only slightly lower than those for lipid-activated CCTα. The importance of the membrane-binding segment in vivo was tested by expression of CCTα236 in CHO58 cells, a cell line that is temperature-sensitive for growth and CCTα activity. Expression of wild-type CCTα in these cells complemented the defective growth phenotype when the cells were cultured in complete or delipidated fetal bovine serum. Expression of CCTα236, however, did not complement the growth phenotype in the absence of serum lipids. These cells were capable of making phosphatidylcholine in the delipidated medium, so the inability of the cells to grow was not due to defective phosphatidylcholine synthesis. Supplementation of the delipidated medium with an unsaturated fatty acid allowed growth of CHO58 cells expressing CCTα236. These results indicate that the membrane-binding segment of CCTα has an important role in cellular lipid metabolism.
Testing the Friedmann equation: The expansion of the universe during big-bang nucleosynthesis

In conventional general relativity, the expansion rate H of a Robertson-Walker universe is related to the energy density by the Friedmann equation. Aside from the present day, the only epoch at which we can constrain the expansion history in a model-independent way is during Big-Bang Nucleosynthesis (BBN). We consider a simple two-parameter characterization of the behavior of H during BBN and derive constraints on this parameter space, finding that the allowed region of parameter space is essentially one-dimensional. We also study the effects of a large neutrino asymmetry within this framework. Our results provide a simple way to compare an alternative cosmology to the observational requirement of matching the primordial abundances of the light elements.
Multimetallic, double-stranded helical complexes derived from hexa(n-propylthio)novipyridine: synthesis, structure and redox properties ☆

4′,4′′,4′′′,4′′′′′,4′′′′′′,4′′′′′′′-Hexa(n-propylthio)-2,2′;6′,2′′:6′′,2′′′:6′′′,2′′′′:6′′′′,2′′′′′:6′′′′′,2′′′′′′:6′′′′′′,2′′′′′′′:6′′′′′′′,2′′′′′′′′-novipyridine (L), a new nonadentate ligand, reacts with cuprous tetrakis(acetonitrile) hexafluoro-phosphate in oxygen-free methanol at room temperature to yield the black, crystalline cuprous complex [L2CuI5][PF6]5. In the presence of air the corresponding mixed-valence complex [L2CuIICuI3][PF6]5 is obtained. Reaction with CuII and CoII ions resulted in the formation of the corresponding trimetallic complexes [L2MII3][PF6]6. Molecular compositions were established from partial elemental analysis, FAB mass spectral data, and from electrochemical and electronic spectral data. [L2CuI5]5+ contains the most cuprous ions assembled in a oligopyridine complex to date and these complexes, analogous to others in this series, were assigned double-stranded helical structures. An intramolecular diastereotopic effect in the 1H NMR spectrum of the diamagnetic pentacuprous complex showed its chiral nature and its stability in solution. Electrochemical studies of these complexes showed appreciable metal–metal interactions, and redox-induced transformations among the copper helicates were established spectroelectrochemically.
A novel method to ascertain sample mass thickness and matrix effects for X-ray fluorescence element determinations

An x-ray fluorescence method was developed for the determination of both trace and major elements in environmental samples that are primarily of geochemical origin. For analysis, unweighed finely pulverized sample material is lightly compressed to a mass thickness between 0.1 and 0.4 g cm−2. The method utilizes the relative intensities of two incoherent and one coherent scattered excitation radiation to ascertain the sample mass thickness and the photoelectric cross-section of the sample for the excitation radiation. This information is employed to calculate matrix absorption and enhancement effect corrections required for the individual element determinations. The intensity of one of the incoherently scattered radiations serves as an internal standard for all of the element determinations. The capability of the method has been demonstrated with three US National Institute of Standards and Technology reference materials. The concentrations of sixteen trace elements (Mn, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th) and four major elements (K, Ca, Ti, and Fe) were determined from one x-ray spectrum which was acquired over a 1000 s counting interval.
Daily pain and symptoms in children with polyarticular arthritis.

Objective To analyze patterns of daily pain, stiffness, and fatigue related to juvenile arthritis; to examine the relationships of demographics, disease severity, and psychological adjustment to daily disease symptoms; and to examine daily disease symptoms as predictors of reduced participation in school and social activity. Methods For a 2-month period, 41 children with polyarticular juvenile arthritis completed daily diaries that included measures of symptoms and function. Children also underwent an initial evaluation and 4 followup evaluations that included a joint count, laboratory testing, and completion of questionnaires assessing physical and psychosocial functioning. Results Children reported having pain an average of 73% of days, with the majority of children (76%) reporting pain on >60% of all days. On average, children described the intensity of their daily pain as being in the mild to moderate range; however, a significant subgroup (31%) reported pain in the severe range. Higher physician global assessment ratings, increased functional disability, and increased anxiety were significantly associated with increased daily pain and other daily symptoms. Multilevel random-effects analyses indicated that increased daily symptoms of pain, stiffness, and fatigue were significant predictors of reduced participation in school and social activities. Conclusion Physicians should consider treating pain more aggressively in children with arthritis, in order to preserve function in school and social domains, as well as physical function. Moreover, optimal pain management in children with arthritis should include therapeutic regimens addressing anxiety as well as standard pharmacologic interventions.
PDGF induces osteoprotegerin expression in vascular smooth muscle cells by multiple signal pathways.

Osteoprotegerin (OPG) is a key regulator of osteoclastogenesis. Recent reports suggest that OPG may function as a protector of arterial calcification and survival of endothelial cells. However, the role and expression of OPG in vascular wall is unclear. Here we report that OPG was highly expressed in vascular smooth muscle cells (VSMC) but not in endothelial cells. Platelet-derived growth factor (PDGF), basic fibroblast growth factor, angiotensin II, tumor necrosis factor α and interleukin-1β upregulated OPG expression in VSMC. Moreover, inhibition of phosphatidylinositol 3-kinase/Akt or P38-signal pathway abrogated PDGF-induced OPG expression. Our results suggest that OPG may be an important determinant of vascular homeostasis.
On the Cook-Kuroda criterion in scattering theory

A new criterion of the Cook-Kuroda type for the existence of the wave operator in the two-space scattering theory is introduced. The condition is quite simple, but it generalizes not only the original Cook-Kuroda condition but also its generalization recently given by Schechter. Specialized to the one-space case, it is actually equivalent to Schechter's condition for an optimal choice of factorization. An application to potential scattering leads to a new result.
Magnetic resonance imaging of pediatric musculoskeletal trauma.

Summary:Musculoskeletal injury in children is common and can lead to lifelong disability. The unique ability of magnetic resonance imaging (MRI) to visualize the cartilaginous ends of growing bones, bone marrow, and supporting soft-tissue structures makes it ideally suited for evaluation of injury i
Candidates for the inflaton in quiver gauge theory

The inflaton necessary to implement the mechanism of inflationary cosmology has natural candidates in quiver gauge theory. We discuss the dimensionless coefficients of quartic couplings and enumerate scalars which are singlet under the low-energy gauge group. The inflaton mass is generally predicted to be in the TeV region, close to 4 TeV for one specific unified model. A quartic inflaton potential, and a mutated hybrid inflation, are discussed. They can give adequate inflation and appropriate fluctuations but different spectral indices.
Emerging Uses of Ultrasonography in Obstetrics

Ultrasonography has become a valuable tool for the assessment and management of a number of obstetrical problems. This communication describes the diagnostic capabilities of the currently available units and the use of ultrasonography as an essential component of amniocentesis, intrauterine transfusion, and fetoscopy.
Transition energy staggering and band interaction in rare-earth nuclei

Abstract Staggering of the transition energies Eγ and moments of inertia J (2) for rotational bands in rare-earth nuclei is investigated by means of the higher order derivatives ΔnEγ (n = 2,3,4). It is shown that these (ΔI = 2) staggering effects in the normally deformed bands are related to band interaction. The band interaction picture is also applied to staggering effects in superdeformed bands.
Alternative Approach to Use of Pulse Width Modulation

There are many requirements placed on the new generation of micro and macro robots, such as communication between robots, allowing coordinated actions, cognitive capabilities, smart behavior, etc. A pulse-width modulation (PWM) is widely used in different areas of control systems, such as robotics, industrial process control, power control systems, etc. A PWM circuit converts a DC voltage into a series of pulses, so that the pulse duration is directly proportional to the value of DC voltage. In spite of wide use of PWM, there are disadvantages of using PWM such as the possibility of generating radio-frequency interferences (RFI). In addition, when control by frequency modulation (FM) is desired the ON-period of PWM pulse is kept constant, but the frequency is varied in order to bring regulation. It is difficult to make the ON-period below a certain time duration. When the limit is reached, control by a PWM becomes impossible. The value of a minimum ON-period depends on the transistor switch. Due to the varying pulse width, PWM is unusable for time division multiplexing (TDM). Usually these problems are encountered when a 555 IC timer is employed as PWM. In this paper we propose two alternative methods for PWM.
Cytogenetic toxicity of gentian violet and crystal violet on mammalian cells in vitro

Abstract The cytogenetic toxicity of gentian violet in Chinese hamster CHO cells in vitro has been studied by analyzing (1) squash preparations from direct fixation for recording mitotic anomalies and (2) air-dried preparations (with colcemid—hypotonic pretreatments) for recording metaphase chromosome aberrations. It was concluded that this compound is a mitotic poison as well as a clastogen in vitro. Its clastogenic property was confirmed in 5 other different mammalian cel types. 10 samples of different gentian violet and crystal violet were surveyed and all were shown to be clastogenic. Unless in vivo studies prove otherwise, gentian violet and crystal violet should be regarded as biohazardous substances.
A simple concept shutter for high energy X-ray beams

Abstract A new design of a high speed shutter system which provides a uniform exposure is described in this paper. The elements of the system are specified. The material for the shutter plates are chosen so that when the system is shut down no X-ray transmission will occur. The mathematical model of the system is derived. The dynamic performance of the electromechanical system driving the shutter plates is optimized by satisfying the requirements for safety, overshoot and speed. A constrained optimization technique is applied for this purpose. The general design approach utilized in this work provides maximum flexibility for the construction of the system which allows for a safe operation with a high speed.
Basement: Not the Bottom But the Beginning: ABSTRACT

Borehole myopia, isotropism, and symmetresis are occupational geological diseases of petroleum geologists End_Page 524------------------------------ and geophysicists which inhibit effective analysis of data as well as development of sound exploration philosophy. Understanding of the nature of the basement and its relation to and influence on sedimentary basins is the first step back to geological health. End_of_Article - Last_Page 525------------
Signal design for infinite impulse response inverse filters

An infinite impulse response (IIR) inverse filter structure is presented, and compared with the performance of two finite impulse response (FIR) designs. The IIR design is shown to provide better performance and be able to improve further (e.g., -1.4 dB in sidelobe levels per unit delay increase for a length-13 Barker sequence) by increasing delay. The performance parameters of this IIR inverse filter suggest a design criterion for sequences on which the filter operates, that is related to the roots of the sequence's Z transform polynomial. The optimal sequence derived according to this criterion is shown to provide sharper sidelobe reduction (-6 dB per unit delay increase for the optimal length-13 sequence). >
Providing Services to Survivors of Domestic Violence A Comparison of Rural and Urban Service Provider Perceptions

Although there is a considerable body of knowledge about domestic violence, a limited proportion focuses on domestic violence in rural settings. Using a nonprobability purposive sampling technique, 93 providers of domestic violence services from rural and urban localities in North Carolina and Virginia were located and asked to complete a self-administered survey soliciting provider perceptions about service consumers, the general public, themselves, and inter- and intra-agency issues. Significant differences were observed between rural and urban providers about service consumer needs and experiences, perceptions about the general public, area resource availability, agency funding, provider training, and worker safety. Implications of these differences are discussed.
Religious Participation and Economic Conservatism

Why do some individuals engage in more religious activity than others? And how does this religious activity influence their economic attitudes? We present a formal model in which individuals derive utility from both secular and religious sources. Our model, which incorporates both demand-side and supply-side explanations of religion, is unusual in that it endogenizes both an individual's religious participation and her preferences over economic policy. Using data on over 70 countries from the pooled World Values Survey, we find that religious participation declines with societal development, an individual's ability to produce secular goods, and state regulations on religion, but that it increases with inequality. We also find that religious participation increases economic conservatism among the poor but decreases it among the rich. Our analysis has important insights for the debate about secularization theory and challenges conventional wisdom regarding the relationship between religious participation and economic conservatism.
BEYOND DARK AND BRIGHT: TOWARDS A MORE HOLISTIC UNDERSTANDING OF INTER‐GROUP NETWORKS

Networks are becoming a popular organizational form for structuring human activities. To date, scholars have addressed networks in a variety of fields, including sociology, economics, public administration, criminology, political science, and international security. However, little has been done so far to systematically examine the similarities, differences, and connections between network forms of organization across different academic disciplines. This has important implications for both theory and practice. The lack of attention paid to organizational similarities and differences prevents the exchange of knowledge developed across fields. In turn, policy-makers cannot take full advantage of existing research, and may miss opportunities to improve the work of some networks and combat that of others. To address this gap in the literature, this paper uses the combination of organizational environments and organizational goals to develop a new typology of inter-group networks, and thus improve our understanding of how human behaviour is coordinated through networks.
Understanding energy consumption of sensor enabled applications on mobile phones

Recent research in ubiquitous and mobile computing uses mobile phones and wearable accelerometers to monitor individuals’ physical activities for personalized and proactive health care. The goal of this project is to measure and reduce the energy demand placed on mobile phones that monitor individuals’ physical activities for extended periods of time with limited access to battery recharging and mobile phone reception. Many issues must be addressed before mobile phones become a viable platform for remote health monitoring, including: security, reliability, privacy, and, most importantly, energy. Mobile phones are battery-operated, making energy a critical resource that must be carefully managed to ensure the longest running time before the battery is depleted. In a sense, all other issues are secondary, since the mobile phone will simply not function without energy. In this project, we therefore focus on understanding the energy consumption of a mobile phone that runs MIT wockets, physical activity monitoring applications, and consider ways to reduce its energy consumption.
Numerical Simulation of a Spark Ignition Engine Using Liquid Fuels and Liquid Fuel Blends

The use of alternative fuels such as methanol and ethanol in spark-ignition (SI) engines is beneficial to the environment as it reduces emissions of pollutants such as NOx from these engines with slight penalty on the performance. This paper investigated the use of liquid fuel blends such as ethanol/gasoline blend in an SI engine by numerical simulations. The numerical simulations were based on the models of finite heat release, cylinder heat transfer, pumping losses, and friction losses. Simulations were carried out to evaluate the effects of compression ratio, equivalence ratio, ignition timing, and engine speed on the performance of the SI engine. The results of the simulations were compared with experimental data from the literature to validate the simulations. Good agreements between the computed and experimental results were obtained. The results showed that the current model could satisfactorily predict the performance of an SI engine fueled by liquid fuel blends.Copyright © 2003 by ASME
Thermodynamic solution properties of aluminous clinopyroxenes: Nonlinear least squares refinements

Abstract The thermodynamic properties of clinopyroxenes on the joins diopside-jadeite, CaTs-jadeite and diopside-CaTs were determined from phase equilibria and calorimetric data. For these coupled solid solutions, the random model, in which the entropy is calculated as if atoms mixed randomly on each site, is used as a base along with a formulation for the excess entropy. A non-linear least squares technique is used that has the correct functional form for weighting the data and allows determination of errors in functions calculated from derived thermodynamic parameters. The derived thermodynamic properties differ significantly from those obtained using linear regression. The excess entropy relative to the random model is negative due to short-range order, but the random model is nevertheless appropriate as a first approximation. The derived mixing entropies are compared with those obtained from a statistical mechanical model using scaled ordering energies determined from electrostatic energy calculations. There is no justification from either experimental data or theoretical considerations for continued use of molecular models for coupled solid solutions, in which the activity is taken as proportional to a mole fraction, which itself is not unambiguously defined.
Clinical Trials in Uremia—Time to Reappraise

The construct of any road map of the progress of medical knowledge reveals a long and tortuous road, full of errors, misapprehensions, blind alleys, and a perpetual shuffling between authority, heresy, and reason; but one of continuous growth and steady progress, albeit at variable pace and achievement at different periods of history. Numerous factors account for this cumulative progress, notable among which are the transmission, scientification, and mathematization of medical knowledge that ultimately account for the progressive evolution of medical care over time, from its primitive beginnings in antiquity to its present sophisticated state of accomplishment. It was the mathematical precision provided by quantification and statistical analysis that established certainty in medicine and ultimately changed the conjectural art of clinical practice to a disciplined science founded on clinical investigation, especially in therapeutics. Randomized clinical trials (RCTs) introduced in the 1950s have since been instrumental in establishing certainty in the practice of medicine. Regrettably, the proliferation of RCTs driven by biased hypotheses and pharmaceutical-industrial interests have created serious flaws in the results of the onslaught of new RCTs that need to be reappraised. Another unfortunate trade-off during this evolution has been neglect of the individual patient's inborn biological variation from the norm, mean, or median, an omission that has come to erode the personal in medical care.
Cranial ontogeny in Philautus silus (Anura: Ranidae: Rhacophorinae) reveals few similarities with other direct-developing anurans.

Direct development has evolved in rhaco- phorine frogs independently from other anuran lineages, thereby offering an opportunity to assess features associ- ated with this derived life history. Using a developmen- tal series of the direct-developing Philautus silus (Ranidae: Rhacophorinae) from Sri Lanka, we examine features of cranial morphology that are part of a suite of adaptations that facilitate feeding in free-living tadpoles, but have been changed or lost in other direct-developing lineages. Larval-specific upper jaw cartilages, which are absent from many non-rhacophorine direct-developing species (such as Eleutherodactylus coqui), develop in embryos of P. silus. Similarly, lower jaw cartilages ini- tially assume a larval morphology, which is subsequently remodeled into the adult jaw configuration before hatch- ing. However, the cartilaginous jaw suspension and hyobranchial skeleton never assume a typical larval morphology. The palatoquadrate, which suspends the lower jaw, lacks the posterior connections to the brain- case found in many metamorphosing species. Unlike in metamorphosing species, bone formation in P. silus begins before hatching. However, the sequence of bone formation resembles that of metamorphosing anurans more than that of other direct developers. In particular, P. silus does not exhibit precocious ossification of the lower jaw, which is characteristic of some frogs and cae- cilians that lack a free-living tadpole. These data reveal some similarities between Philautus and other direct- developing anurans. However, the departure of Phi- lautus embryos from the generalized tadpole skeletal morphology is less pronounced than that observed in other direct-developing taxa. J. Morphol. 268:715-725, 2007. 2007 Wiley-Liss, Inc.
Upper bounds for the fundamental eigenvalue for a domain of unknown shape

For a particular eigenvalue problem in partial differential equations, upper bounds are established which do not depend on the shape of the domain but only on its size. The problem describes the free sloshing motions of an incompressible, inviscid fluid in a canal and furnishes upper bounds to the highest fundamental sloshing frequency which is attainable for a given cross-section area of the canal.
An institutional approach to donor control : From dyadic ties to a field-level analysis

Literature on the nonprofit sector focuses on charities and their interactions with clients or governmental agencies; donors are studied less often. Studies on philanthropy do examine donors but tend to focus on microlevel factors to explain their behavior. This study, in contrast, draws on institutional theory to show that macrolevel factors affect donor behavior. It also extends the institutional framework by examining the field‐level configurations in which donors and fundraisers are embedded. Employing the case of workplace charity, this new model highlights how the composition of the organizational field structures fundraisers and donors alike, shaping fundraisers’ strategies of solicitation and, therefore, the extent of donor control.
A molecular mechanical model that reproduces the relative energies for chair and twist‐boat conformations of 1,3‐dioxanes

We present molecular mechanics calculations on the conformational energies of several 2,2-dimethyl-trans-4,6-disubstituted-1,3-dioxanes. Previous studies by Rychnovsky et al.1 have suggested that the relative conformational energies of chair and twist-boat forms of these 1,3-dioxanes were poorly represented by the molecular mechanical models MM2* and MM3* (MacroModel2 implementations of MM2 and MM3) both when compared to experiment and to high-level quantum mechanical calculations. We have studied these molecules with a molecular mechanical force field which features electrostatic-potential-based atomic charges. This model does an excellent job of reproducing the relative conformational energies of the highest level of theory (MP2/6-31G*) applied to the problem. Furthermore, when empirically corrected using the MP2/6-31G* relative conformational energies of the unsubstituted compound 2,2,4-trimethyl-1,3-dioxane, the absolute energy differences calculated with this new model between the chair and twist-boat conformers for five substituted compounds are within an average of 0.30 kcal/mol of the MP2/6-31G* values. The correlation with experiment is also very good. One can, however, modify the initial molecular mechanical model with a single V1(OCOC) torsional potential and do an excellent job in reproducing the absolute conformational energies of the dioxanes as well, with an average error in conformational energies of 0.45 kcal/mol. This same torsional potential was independently developed by comparing ab initio and molecular mechanical energies of the molecule 1,1-dimethoxymethane. Thus, we have succeeded in developing a general molecular mechanical model for 1,3-dioxoalkanes. In addition, we have compared the standard MM2 and MM3 models with MM2* and MM3* (ref. 2) and have found some significant differences in relative conformational energies between MM2 and MM2*. MM2 has an improved correlation with the best ab initio data compared to MM2* but is still significantly worse than that found with lower-level ab initio or AM1 semiempirical quantum mechanics or the new molecular mechanical model presented here. MM3 leads to conformational energies very similar to MM3*. Energy component analysis suggests that the single most important element in reproducing the conformational equilibrium is the electrostatic energy. This fact rationalizes the success of AMBER models, whose fundamental tenet is the accurate representation of quantum mechanically calculated molecular electrostatic effects. © 1995 by John Wiley & Sons, Inc.
Computational methods for shape restoration of buried objects in Compton backscatter imaging

Image restoration techniques are studied for Compton backscatter imaging as applied to identification of a land mine buried in soil. Mathematical methods are developed to restore images, which include artifacts due to photon noise, soil surface irregularity, and vertical motion of the imaging system. The image restoration is formulated as an inverse photon transport problem. The forward photon transport is modeled by using a two-collision response function. The inverse problem then is solved by applying an iterative minimization algorithm, resulting in an estimation of characteristic parameters of objects. Mathematical relations among detector responses are derived by experimentally analyzing the detector response characteristics when there are soil surface irregularity and vertical motion of the imaging system. These are used to remove the artifacts from the images. The method successfully restores the geometrical feature of the object under simulated battlefield imaging conditions.
Regulation and Formation of the Drosophila Salivary Glandsa

The homeotic gene, Sex combs reduced (Scr), is a master regulator of Drosophila salivary gland formation. Embryos in which Scr function is missing do not form salivary glands, and embryos in which SCR protein is expressed everywhere form extra salivary glands. However, other known proteins, including the homeotic protein Abdominal-B, the unusual zinc finger protein Teashirt, and the secreted signaling molecule Decapentaplegic (a TGF-beta family member), limit the recruitment of SCR-expressing cells to salivary glands. To learn the molecular details of how salivary gland gene expression is controlled and as a first step toward understanding how the SCR transcription factor controls salivary gland morphogenesis, we screened for genes expressed in the developing salivary gland. Among our best candidates for potential direct downstream targets of SCR in the salivary gland are the genes trachealess (trh), dCREB-A, jalapeno, and Semaphorin II (SemaII). Our genetic studies suggest distinct and important roles for each of these genes in salivary gland morphogenesis. Current work includes studying the molecular interactions between SCR and these downstream target genes and asking how target genes coordinate their activities to effect the cell biological changes required to build functional salivary glands.
Isothermal reversion of the B.C.C.→ H.C.P. transformation induced in β' AgCd by mechanical deformation

Abstract The hexagonal close-packed structure induced in β' AgCd by mechanical deformation was found to revert gradually to the original body-centered cubic structure at room temperature. The rate of reversion was measured for several alloys of composition around 50 at. %. The reversion rate was found to be dependent on composition and temperature; the process appeared to be thermally activated with an activation energy of about 23 kcal/mole. The rate data were found to agree with equations that have been derived by other authors for nucleation and growth processes.
Got It! Let's Cool It! But What's Next in Organ Donor Research?

Keywords: editorial/personal viewpoint; kidney transplantation/nephrology; delayed graft function (DGF); ischemia reperfusion injury (IRI); clinical trial
The American Recovery and Reinvestment Act: Is More Federal Grant Money What the States Need?

To end the current recession, Congress and the Obama administration propose the American Recovery and Reinvestment Act of 2009 (ARRA), an $825 billion fiscal stimulus package made up of tax cuts and federal spending. A significant component of this package consists of federal grants meant to help states facing unprecedented budget shortfalls.While federal grants may provide temporary relief for state budgets, the size and scope of the proposed spending will worsen already-distorted state and local fiscal practices while creating perverse incentives inducing greater public spending with scarce state funds. By fracturing the link between those who benefit (local constituencies) and those who pay (federal taxpayers), ARRA reduces government accountability on all levels and ultimately erodes local control over policy by imposing federal solutions on local problems.Instead of attempting a short-term fix of amplifying the grant system through an emergency stimulus package, the federal government should work to make state and local governments accountable for their own spending decisions. This means reducing states' and localities' reliance on federal funding for local priorities and allowing local activities to be addressed by the appropriate mechanisms: state and local governments and the private and philanthropic sectors.
Controlling kinetics of heterogeneous sol–gel solution for high-performance adhesive hybrid films

The strength of bonding at epoxy/SiO2 interface and its susceptibility to environmental degradation have profound impact on the lifetime and reliability of microelectronic devices. The incorporation of hybrid film at epoxy/SiO2 interfaces has been shown to alleviate this challenge, but the working time to produce these highly-adherent hybrid films on silicon has been limited to ~10 min. In this work we demonstrate that, by lowering sol–gel aging temperature to 5 °C, the processing window for producing highly-adherent hybrid films on silicon can be extended to more than 6 h. In addition to the extended processing time, an Arrhenius type relationship between sol–gel aging temperature and the optimal sol–gel aging time was observed, with an overall sol–gel reaction activation energy of approximately 2.03 eV/atom that includes both hydrolysis and polycondensation. The enhanced interfacial adhesion was explained in terms of the graded hybrid film structure as determined by X-ray photoelectron spectroscopy depth profiling. The work has significant implications for the successful integration of hybrid film strategy in device packaging technologies. Fracture energy of epoxy/hybrid-film/SiO2 structures with films prepared at different sol–gel aging times and temperatures. Black, red and blue curves show fracture energy as a function of sol-gel aging time for solutions aged at 25, 15 and 5 °C respectively. Grey dashed line indicates Gc = 60 J/m2 while orange dot-dash line represents the adhesion of epoxy/SiO2 interface in the absence of the hybrid film.
Questions of Data Ownership on Campus

Valid arguments exist for students to control data about themselves, and similarly plausible arguments suggest that the institution can claim ownership. This article explores both perspectives. To avoid win-lose solutions, institutions acting as "information fiduciaries" can reap the benefits of analyzing student data while respecting student rights.
Biometric authentication

In this age of digital impersonation, biometric techniques are being used increasingly as a hedge against identity theft. The premise is that a biometric - a measurable physical characteristic or behavioral trait - is a more reliable indicator of identity than legacy systems such as passwords and PINs. There are three general ways to identify yourself to a computer system, based on what you know, what you have, or who you are. Biometrics belong to the "who you are" class and can be subdivided into behavioral and physiological approaches. Behavioral approaches include signature recognition, voice recognition, keystroke dynamics, and gait analysis. Physiological approaches include fingerprints; iris and retina scans; hand, finger, face, and ear geometry; hand vein and nail bed recognition; DNA; and palm prints. In this article, we focus on the two most popular biometric techniques: fingerprints and iris scans.
Poe's Pendulum

The study of the motion of a steadily descending pendulum has practical applications (e.g., to the oscillations of a load being lowered by a crane). Our interest, however, was stimulated not by practicality but by a striking literary work in which a descending pendulum plays the role of an infernal machine. The story is Edgar Allan Poe's classic tale "The Pit and the Pendulum," written in 1842 and familiar to generations of aficionados of the macabre. In his customary florid style Poe tells of a prisoner bound flat on the floor of a chamber of horrors:
Chronic transcranial focal stimulation from tripolar concentric ring electrodes does not disrupt memory formation in rats

Non-invasive electrical brain stimulation has shown potential utility as a treatment for seizures in epilepsy patients. Transcranial focal stimulation (TFS) via tripolar concentric ring electrodes (TCREs) has been effective in reducing seizure severity in acute rodent models, but it has yet to be determined whether or not it will serve as a viable long-term treatment strategy. Prior experiments indicate that a single dose of TFS via TCRE does not impact short- or long-term memory formation. The present study investigated if five daily doses of TFS via a TCRE on the scalp affected the memory. The spontaneous object recognition (SOR) test was used to evaluate the memory. Sham and TFS-treated groups were evaluated and both showed comparable levels of preference for novel objects, indicating successful memory formation. More work on repeated dosage strategies is important for establishing the safety and efficacy of TFS as a putative treatment.