cssi/SciSciGPT-SciSciNet huggingface dataset:
Enhanced reversibility and unusual microstructure of a phase-transforming material

The enhanced reversibility (stable transition temperature even at high strain under a solid-to-solid phase transition), low hysteresis and unusual riverine microstructure (ranging through thermal cycles) of the martensitic material Zn45Au30Cu25 makes it attractive for applications from eco-friendly fridges to medical sensors. Martensitic transformations are diffusionless, solid-to-solid phase transformations characterized by a change of crystal structure that can often be very useful. Applications include medical sensors, eco-friendly refrigerators and energy conversion devices. Repeated transformation cycles, however, can cause thermal hysteresis that modifies the material's properties and can cause permanent damage. Here Richard James and colleagues report the development of a martensitic alloy of zinc, gold and copper that maintains near-reproducible macroscopic properties despite drastic changes in its microstructure during each cycle. As well as providing a system that throws new light on the effects of hysteresis on reversible martensitic phase transformations, this work could help to extend applications for the materials in new areas — towards shape memory alloys for instance. Materials undergoing reversible solid-to-solid martensitic phase transformations are desirable for applications in medical sensors and actuators1, eco-friendly refrigerators2,3 and energy conversion devices4. The ability to pass back and forth through the phase transformation many times without degradation of properties (termed ‘reversibility’) is critical for these applications. Materials tuned to satisfy a certain geometric compatibility condition have been shown2,5,6,7,8,9,10,11,12,13,14 to exhibit high reversibility, measured by low hysteresis and small migration of transformation temperature under cycling6,9,12,15. Recently, stronger compatibility conditions called the ‘cofactor conditions’5,15 have been proposed theoretically to achieve even better reversibility. Here we report the enhanced reversibility and unusual microstructure of the first martensitic material, Zn45Au30Cu25, that closely satisfies the cofactor conditions. We observe four striking properties of this material. (1) Despite a transformation strain of 8%, the transformation temperature shifts less than 0.5 °C after more than 16,000 thermal cycles. For comparison, the transformation temperature of the ubiquitous NiTi alloy shifts up to 20 °C in the first 20 cycles9,16. (2) The hysteresis remains approximately 2 °C during this cycling. For comparison, the hysteresis of the NiTi alloy is up to 70 °C (refs 9, 12). (3) The alloy exhibits an unusual riverine microstructure of martensite not seen in other martensites. (4) Unlike that of typical polycrystal martensites, its microstructure changes drastically in consecutive transformation cycles, whereas macroscopic properties such as transformation temperature and latent heat are nearly reproducible. These results promise a concrete strategy for seeking ultra-reliable martensitic materials.
Neonatal treatment with nerve growth factor antiserum eliminates cholinergic sympathetic innervation of rat sweat glands

Most mammalian sympathetic neurons are noradrenergic, and their dependence upon nerve growth factor (NGF) for survival during development is well established. A minor population of sympathetic neurons, including those that innervate sweat glands, is cholinergic. To determine whether cholinergic sympathetic neurons, like their noradrenergic counterparts, require NGF during development, neonatal rats were treated with NGF-antiserum and 3 weeks later their sweat glands were examined for the presence of innervation. Acetylcholinesterase (AChE) staining and vasoactive intestinal polypeptide-like immunoreactivity (VIP-IR) which mark the mature sweat gland innervation were absent from the sweat glands of the anti-NGF treated animals. Further, when the glands were examined with the electron microscope, no axons or nerve terminals were evident. These observations indicate that the elaboration of the sweat gland plexus is NGF-dependent and suggest that at least one population of cholinergic sympathetic neurons in the rat requires NGF for survival. Our findings are consistent with the idea that during development NGF is a required trophic factor not only for noradrenergic sympathetic but also for cholinergic sympathetic neurons.
WOODY DEBRIS ON THE MAINLAND SHELF OFF VENTURA, SOUTHERN CALIFORNIA

SUMMARY Land plant debris occurs in appreciable quantities in the shelf sediments off Ventura, southern California. Concentrations range from less than 2 g (wet weight)/1 (less than 250 g/m2) to 53 g/1 (10,662 g/m2). The highest values are found near the outer edge of the shelf.
The utilization and fate of β-sitosterol in the larva of the housefly, Musca domestica L.

Abstract Using H 3 - β -sitosterol, gas-liquid chromatographic analysis, and a semi-defined diet with aseptic rearing techniques, it was demonstrated that larvae of the houselfy, Musca domestica , do not dealkylate β -sitosterol to form cholesterol. Furthermore, the major sterol (>99 per cent) isolated from insects reared in the above manner on a diet containing pure unlabelled β -sitosterol (100 per cent by GLC) was identified as unchanged β -sitosterol. β -Sitosterol, campesterol, and cholesterol were also compared in nutritional tests in which each of these three sterols served as a sole source of sterol in both the adult and larval diets. β -Sitosterol was only approximately one-fourth as effective as either cholesterol or campesterol in supporting larval growth and development. In addition, only 1·4 per cent of the organisms from the diet containing β -sitosterol emerged as adults and these failed to produce viable eggs. These results demonstrate conclusively that β -sitosterol is not converted to cholesterol in the housefly and that this sterol will not fulfil in entirety the sterol requirement of this insect.
Designing and assessing effective classroom writing assignments for NES and ESL students

Abstract Academic writing is a form of testing; moreover, for most writing tasks across the U.S. college/university curriculum, the designer of the writing assignment is also the audience and the evaluotor, and that designer-evaluator expects student-writers to demonstrate specific knowledge and skills. Therefore, like all test designers, designers of writing assignments should carefully consider the purpose(s), the parameters and constraints, and the evaluation criteria for each writing assignment. In this article, we discuss a range of issues in the design and assessment of classroom writing tasks assigned in courses across the U.S. college/university curriculum. We use a framework we designed previously to discuss the preparation and evaluate the design of writing tasks. We then analyze successful and unsuccessful writing across the curriculum assignments, particularly from the perspective of English as a second language writers, and offer suggestions that will enable teachers to design and assess effective writing tasks.
Analysis of expanded-food texture by image processing : Part II : Mechanical properties

Image texture and color features were used to represent the mechanical properties of expanded food products. Texture-related mechanical properties were measured through Instron shear and compression tests. the image features extracted were found highly correlated with the mechanical properties. the analysis showed useful relationships between geometric properties and mechanical behavior. Image processing proved to be an effective technique for textural analysis of expanded food products.
Determination of nanomolar levels of formate in natural waters based on a luminescence enzymatic assay

Abstract A light-producing reaction utilizing three enzymes, bacterial luciferase, dehydrogenase and diaphorase, can be used to determine formic acid in natural waters at nanomolar concentrations. The method is rapid and convenient, requiring no preconcentration, desalting or derivatization procedures. Determinations can be done on small sample volumes (25 μl) at room temperature and pH 7. The precision (relative standard deviation for sea water samples containing 1.0 μM formate was 9.0% ( n = 15). The reaction is specific for formate with a detection limit of 20 nM (signal-to-noise ratio = 3). Results for applications of the method to sea, estuarine and rain water are given.
REVIEW OF HEAT TRANSFER TO HELIUM I.

Abstract This paper reviews heat transfer to helium I. Recommendations are made for expressions to be used in design studies and for further work required to produce information that is needed.
Friction modeling and compensation for an industrial robot

This article describes the detailed friction modeling of the General Electric GP132 industrial robot. Friction is an area whose importance is often discounted in the development of control systems because it is thought to be insignificant or unmodelable. This work demonstrates that friction does have a predictable structure, and that significant performance improvement can be realized through its proper compensation. Experiments performed to determine the static, Coulomb, and viscous friction of the GP132 are presented. In addition to these components, the robot is shown to have significant gravity load-dependent and position-dependent friction. The accuracy of the friction models are verified through several experiments and are shown to be considerably better than previously formulated models.
Airborne geophysical study in the pensacola mountains of antarctica.

A seismic reflection, gravity, and aeromagnetic reconnaissance was made in the Pensacola Mountains, Antarctica, during the 1965-66 austral summer. Prominent ice streams located between the Neptune and Patuxent Ranges and east of the Forrestal Range overlie channels in the rock surface 2000 meters below sea level which are probably of glacial origin. Seismic reflections show that the Filchner Ice Shelf is 1270 meters thick near its southern margin. Along the boundary between West and East Antarctica, Bouguer anomalies decrease from +60 milligals in West Antarctica to —80 milligals in East Antarctica. An abrupt change in crustal structure across this boundary is required to explainl the 2 milligals per kilometer gradient. This may indicate a fault extending through the crust into the mantle. Aeromagnetic profiles delineate anomalies up to 1800 γ associated with the basic stratiform intrusion which comprises the Dufek and Forrestal ranges. A probable minimum area of 9500 square kilometers is calculated for the intrusive body on the basis of the magnetic anomalies, making it one of the largest bodies of its type. The extension of this magnetic anominaly across a fault forming the north border of the Pensacola Mountains probably precludes transcurrent movement.
Identification of functionally related neural assemblies.

Summary Present-day techniques of multiple-electrode recording together with computer-aided separation of impulses arising from different neurons permit the simultaneous recording of nerve-impulse timings in sets of neurons exceeding 20 in number. This in turn makes it feasible to search for functional groups of neurons, defined as subsets that tend to fire in near simultaneity significantly more often than would independent neurons at corresponding mean rates. A statistical technique is described that permits the detection and identification of such functional groups. The method is accretional, based on identification of associated neurons through iterative application of a significance test on multiple coincidences of neuronal firings within an observational window. Examples of the operation of the method and indications as to its sensitivity are furnished through computer simulations of neural network. The entire algorithm may be used a screening technique to select smaller groups of neurons for cross-corelational and related finer-grained temporal analyses, or it may be used in its own right to detect and characterize functional groups that are not distinguishable by other statistical procedures.
Power Line Conducted Interference Measurement Differences Using U. S. and CISPR Line Impedance Stabilization Networks

Measurements of power line conducted interference are commonly made on commercial equipment throughout the world using line impedance stabilization network (LISN's) in accordance with industrial and governmental procedures. Procedures in the United States applying to the 0.15-30 MHz frequency range specify an LISN that presents a frequency-dependent RF impedance to the equipment under test (EUT) whereas other national practices specify as LISN having an invariant 150-ohm impedance. This paper explores the expected measurement differences resulting from use of the two LISN's for power line interference measurements. Calculated difference factors, which depend on the EUT power line RF-input impedance, are developed. The factors have utility in assessing expected conducted interference levels in one LISN measurement configuration, given the interference levels and impedance parameters of the other. Measurement differences, in addition to those introduced by the LISN, which are attributed to variations in specified field strength meter parameters (i. e., detector, bandwidth, mechanical time constants, etc.) are beyond the scope of this paper.
Finding cluster centers and sizes via multinomial parameterization

The clustering problem consists in dividing a data set into groups of observations that are similar within but different across. This paper presents a method for assessment the clusters centers and sizes in a non-linear least squares optimization with multinomial parameterization. The method is especially useful for large data sets as it operates on the summary statistics only. This approach also works for the problem of finding clusters' centers and sizes by the covariance matrix when the original data is not available. Estimation of the clusters centers and sizes can be followed by actual clustering. Example of application to marketing research problem is discussed.
Myristylation and palmitylation of HSV-1 UL11 are not essential for its function

All herpesviruses encode a homolog of the herpes simplex virus type-1 UL11 tegument protein. Deletion of UL11 disrupts virus envelopment, causes capsid accumulation within the cytoplasm, and reduces virus release. UL11 requires acylation with myristate and palmitate for membrane binding, lipid raft trafficking, and accumulation at the site of virus envelopment. Thus, it was predicted that acylation of UL11 would be necessary for efficient virion production, similar to HIV-1 Gag which requires myristylation for virus production. Accordingly, recombinant viruses were created to express UL11 derivatives that are not acylated, are partially acylated, or contain foreign acylation signals. Unexpectedly, the non-acylated UL11 rescued some growth defects of a UL11-null mutant, even though the unmodified protein was unstable. Furthermore, a myristylated and palmitylated chimera did not fully rescue the null virus. These results suggest that UL11 maintains some function(s) when not membrane-bound, and the sequence context of the acylations is important for UL11 function.
Effect of 5% albumin solution on sodium balance and blood volume after subarachnoid hemorrhage.

Objective Subarachnoid hemorrhage (SAH) predisposes patients to excessive natriuresis and volume contraction. We studied the effects of postoperative administration of 5% albumin solution on sodium balance and blood volume after SAH. We also sought to identify physiological variables that influence renal sodium excretion after SAH. Methods Forty-three patients with acute SAH were randomly assigned to receive hypervolemia or normovolemia treatment for a period of 7 days after aneurysm clipping. In addition to a base line infusion of normal saline solution (80 ml/hr), 250 ml of 5% albumin solution was administered every 2 hours for central venous pressure (CVP) values of Results Both groups demonstrated relative volume expansion in base line measurements. The hypervolemia group received significantly more total fluid, sodium, and 5% albumin solution than did the normovolemia group and had higher CVP values and serum albumin levels (all P Conclusion Supplemental 5% albumin solution given to maintain CVP values of >8 mm Hg prevented sodium and fluid losses but did not have an impact on blood volume in our patients, who were hypervolemic in base line measurements. The natriuresis that occurs after SAH may be mediated in part by elevations of GFR. In addition to acting as a colloid volume expander, 5% albumin solution lowers the GFR and promotes renal sodium retention after SAH. These properties may limit the amount of total fluid required to maintain a given CVP value and hence may minimize the frequency of pulmonary edema.
Increased Synthesis of Rat Liver Alkaline Phosphatase by Bile Duct Ligation

The following studies were done to determine the mechanism of the increse in rat liver alkaline phosphatase activity after bile duct ligation. Antiserum was raised in rabbits to highly purified rat liver alkaline phosphatase. In immune titration experiments, the 350% increase in rat liver alkaline phosphatase activity caused by bile duct ligation was paralleled by a similar increase in immuno-precipitated alkaline phosphatase protein. In a second set of experiments, rat liver alkaline phosphatase was labeled with L-[3H]leucine injected into portal veins. Alkaline phosphatase was purified by antibody affinity chromatography followed by immunoprecipitation. The incorporation of L-[3H]leucine into alkaline phosphatase was significantly higher in bile duct-ligated rats than in controls, 68,357 ± 7,144 vs. 19,297 ± 3,076 dpm per gm liver (p < 0.001) and 349 ± 36 vs. 104 ±17 dpm per gm protein (p < 0.001). In a third set of experiments, the incorporation of L-3H-amino acid into highly purified rat liver alkaline phosphatase was measured. Rat liver alkaline phosphatase was purified by means of sequential iV-butanol extraction, antibody affinity column chromatography, preparative polyacrylamide gel electrophoresis, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. There was significantly more L-3H-amino acid incorporated into alkaline phosphatase in bile duct-ligated rats compared to sham-operated rats, 3,565 vs. 704 dpm per gm liver and 19,656 vs. 3,843 dpm/gm protein. The data suggest that bile duct ligation increases the synthesis of rat liver alkaline phosphatase.
The mode of migration of neurons to the hippocampus: a Golgi and electron microscopic analysis in foetal rhesus monkey.

The mode of neuron migration from the site of their origin in the ventricular zone to area CA1 of the hippocampus was analysed with Golgi and electron microscopic methods during the first half of gestation in the foetal rhesus monkey. In the inner portion of the intermediate zone, the migrating cells have a bipolar form with one, or occasionally two, leading processes which do not reach the ammonic plate and with a single trailing process which usually ends within the intermediate zone. Both the nucleus and the cytoplasm of the migrating cells are relatively electron-dense and the latter contains organelles typical of young neurons as described in other brain regions. Analysis of electron micrographs from serial sections reveals that the length of the somata and of the leading and trailing processes of the migrating neurons is apposed to fascicles of radially oriented, electron-lucent, microtubule-filled fibres which are ultrastructurally similar to the radial glial fibres of the neocortex and to the Bergmann glial fibres of the cerebellum. The close (20 nm) apposition between the membranes of the migrating cell and the radial fibre is maintained even in areas where the fibres bend or curve tortuously. Migrating neurons situated at progressively more superficial levels of the intermediate zone become progressively more differentiated and complex. Thus, in the outer portion of the intermediate zone, the migrating cells acquire several additional cytoplasmic processes and occasionally a long thin axon-like process which courses into the incipient alveus. These cells have somewhat larger somata and less electron-dense nuclei and cytoplasm than the migrating neurons still situated in the inner part of the intermediate zone. Cells close to the ammonic plate usually have one to three cytoplasmic processes that enter the ammonic plate and terminate near their presumed final position. Migrating neurons situated at the lower border of the ammonic plate have a single large apical process which intermingles with neurons already in their final position and which sometimes traverses the ammonic plate. The apposition of the migrating neurons to the radial glial processes becomes less explicit as the cell soma enters the ammonic plate, reflecting the more complex three-dimensional intercellular relationships. However, the present analysis indicates that during the middle and late stages of neuronal migration to the hippocampus radial glial fibres may guide postmitotic young neurons across the intermediate zone to the ammonic plate in the same way that they guide neurons migrating to the superficial and middle layers of the neocortical plate.
Improved carrier concentration control in Zn-doped Ca5Al2Sb6

Ca_5Al_2Sb_6 is an inexpensive, Earth-abundant compound that exhibits promising thermoelectric efficiency at temperatures suitable for waste heat recovery. Inspired by our previous study of p-type Ca_(5−x)Na_xAl_2Sb_6, this work investigates doping with Zn^(2+) on the Al^(3+) site (Ca_5Al_(2−x)Zn_xSb_6). We find Zn to be an effective p-type dopant, in contrast to the low solubility limit and poor doping efficiency of Na. Seebeck coefficient measurements indicate that the hole band mass is unaffected by the dopant type in the high-zT temperature range. Band structure and density of states calculations are employed in order to understand the carrier concentration-dependent effective mass. Ca_5Al_(2−x)Zn_xSb_6 has a low lattice thermal conductivity that approaches the predicted minimum value at high temperature (1000 K) due to the complex crystal structure and high mass contrast.
Mechanisms for Formation of a One-Dimensional Horizontal Anodic Aluminum Oxide Nanopore Array on a Si Substrate

A simple theoretical model based on electric-field-assisted growth and dissolution of the barrier oxide has been proposed to understand the mechanisms for formation of a one-dimensional (ID) anodic aluminum oxide (AAO) nanopore array. It is shown that formation of a one-dimensional horizontal nanopore array is the natural result of the self-adjusting effect of anodic oxidation. Because the electric field for anodization is in parallel with an aluminum film, the porous structure is formed on the side of aluminum. When the thickness of an aluminum film approaches the size of a single cell, a single array of nanopores evolves after anodization in a steady state for sufficiently long time. Our experimental results support the theoretical model. A well-ordered one-dimensional nanopore array was obtained at 40 V in 0.3 M oxalic acid solution using the modified two-step anodization procedure.
Problems of Voting

It is now over 200 years since Condorcet discovered a serious paradox in the standard method of voting under substantially any of the rules of order. Most Americans are most familiar with the rules developed by General Robert’s, but almost all sets of rules used in genuinely democratic bodies are similar. A proposal is made and then modifications, called amendments are added. There is then a series of binary votes so arranged that the final outcome is a modified version of the original proposal. The modification can be extreme. Unfortunately, Condorcet discovered that some amendments or proposals, which had been defeated in the earlier part of the voting series, might be able to beat the ultimate outcome. A colleague of Condorcet in the academy proposed another voting method in which all alternatives are listed by each voter and then given a weight depending upon their location in the list. It was immediately pointed out that this method provided strategic opportunities for the voter to cheat by misspecifying his preferences. Borda replied that he designed his system for honest men, but since politics is not full of honest men this was regarded as a weak defense. The problem was largely ignored for the next two centuries. Some mathematicians seem to have been interested and one of them Dodson, better known as Lewis Carrol put in a good deal of work on the matter, but without reaching any solution. People advocating democracy, or for that matter opposing it, seem not to have known about this problem or in any event they did not discuss it. In the 1930s, a mathematician interested in field sports and engaged in scoring sports meets discovered that the method used for scoring in which the winner in a given sport was given five points, the second three points, and the third one point, and these points were aggregated in order to determine which university team won had a serious paradox (see Huntingdon, 1938). Specifically, whether A or B won the meet could be determined by whether C, a weak team was physically present or not. He published this result in a mathematical journal and it was ignored for some time. It was not until the late 40s that Arrow used this as part of his proof that voting methods all have severe difficulties.
Pharmacokinetic Evidence for Improved Ophthalmic Drug Delivery by Reduction of Instilled Volume

The bioavailability of topically applied pilocarpine nitrate was studied as a function of instilled volume. As the instilled volume decreased, the fraction of dose absorbed increased. The relationship between fraction absorbed and instilled volume was not direct, but appropriate adjustment of instilled volume and concentration should permit substantial dosage reductions without sacrifice of drug concentration in the eye. The implications of these findings from both a therapeutic and toxicity standpoint are discussed.
Correlates of Marital Dissolution in a Prospective Fertility Study: A Research Note

Couples whose marriages dissolved during a five year period of a longitudinal fertility study of family growth patterns in the Detroit area show marked differences compared to those who remained married. Data are based on intensive home interviews with a cross-section sample of 1304 women at important family life stages, taken prior to the time of marital disruption. Couples divorced or permanently separated in the subsequent five year period were lower in socioeconomic status than those remaining married, and were also distinctive in fertility patterns. The disparities between aspiration and actuality, marital role perception and role performance, attitudes and actions, which characterize the dissolved marriages are of special interest.
DNAzyme amplification of molecular beacon signal.

This paper reports an improved catalytic molecular beacon. Addition of the target oligonucleotide activates a DNA enzyme (DNAzyme), which, in turn, activates multiple copies of molecular beacons (MB) and gives rise to a strong fluorescence signal. In a previous design, the activated DNAzyme could oligomerize, especially dimerize, and result in inactivation of the DNAzyme. The current design avoids this problem, upon activated by the target DNA, the DNAzyme will stay constantly active. With the improved method, a detection of 10 pM DNA has been demonstrated, which is 1000 times more sensitive than the method previously reported.
Cognitive processing and cognitive ability: A multivariate validity investigation

Abstract What are the underlying sources of cognitive ability differences and of cognitive growth? Recent attention has focused on the experimental isolation of cognitive processing factors in the explanation of performance differences on complex tasks, and a number of research studies show a substantial relation between processing parameters and ability differences. Several validity issues—convergent process measures, differential ability prediction, and multiple levels of analysis—have not been addressed empirically, and these concerns are the focus of this study. Sixty eighth graders (30 F, 30 M) and 60 adults (30 F, 30 M) participated in verbal and spatial assessments, and in six experiments over two sessions. Three experiments were designed to estimate memory retrieval processing and three to estimate mental rotation processing. Two strategy parameters were derived also from these experiments. Within the processing tasks, there was modest convergence for eighth graders but negligible convergence for adults. More importantly, relationships between the processing parameters and the ability indices failed substantially to conform to the theoretically predicted convergent/discriminant pattern. Regression analyses also provided support for these disconforming patterns. The viability of explaining developmental and/or individual] differences using cognitive processing variance is explored.
Synthesis of single-crystal Sm-Co nanoparticles by cluster beam deposition

Single-crystal Sm-Co nanoparticles have been successfully produced by a cluster beam deposition technique. Particles have been deposited by DC magnetron sputtering using high Ar pressures on both single-crystal Si substrates and Au grids for the magnetic and structural/microstructural properties, respectively. Oxidation of the particles is prevented by using carbon buffer and cover layers. Nanoparticles have a uniform size distribution with an average size of 4.2, 6 and 7 nm at 1, 1.5 and 2 Torr of Ar pressure, respectively. At 1 Torr, the particles have the disordered 1:7 structure and a high coercivity of 19 kOe at 10 K. These particles show a superparamagnetic behavior with a blocking temperature of TB = 145 K. From this value of TB and the particle volume, the value of anisotropy constant K is estimated to be around 2.2 × 107 ergs/cc. Heat is introduced to the particles during their flight to the substrate to increase the particle size. Nanoparticles of SmCo5 with an average size of 15 nm and high room temperature coercivity have been produced. No change in magnetic and structural properties of the samples has been observed even after 10 months. Cluster beam deposition could play a key role for the production of rare earth nanoparticles for many applications.
Unitary Highest Weight-Modules of Inductive Limit Lie Algebras and Groups

Abstract Representations of inductive limits of finite-dimensional Lie groups and algebras am our main objects of study. Such representations can be constructed by taking inductive limits of the representations of the finite-dimensional groups or algebras. For (finite dimensional) Lie groups and algebras of Hermitian symmetric type, Enright-Howe-Wallach classified those highest weight representations which are unitarizable. In this paper we consider the limits of the algebras u(p, n), so*(2n) and sp(n, R), the limits of the corresponding maximal compact subgroup and the limits of the corresponding generalized Verma modules. We give necessary and sufficient conditions for the inductive limit representation to be unitarizable. In all three cases we show that a necessary condition for unitarizability is that the highest weight is eventually constant. We also give sufficient conditions (depending on the constant) which will ensure that the limit is unitarizable.
The H1-compact global attractor for the solutions to the Navier-Stokes equations in two-dimensional unbounded domains

We extend previous results obtained by Rosa (1998 Nonlinear Anal. 32 71-85) on the existence of the global attractor for the two-dimensional Navier-Stokes equations on some unbounded domains. We show that if the forcing term is in the natural space H, then the global attractor is compact not only in the L2 norm but also in the H1 norm, and it attracts all bounded sets in H in the metric of V. The proof is based on the concept of asymptotic compactness and the use of the enstrophy equation. As compared with the work of Rosa, which proved the compactness and the attraction in the L2 norm, the new difficulty comes from the fact that the nonlinear term of the Navier-Stokes equations does not disappear from the enstrophy equation, while it does disappear in the energy equation due to its antisymmetry property.
On Compact Modeling of Coupling Effects in Maintenance Processes of Complex Systems

While the complexity of modern engineering systems is significantly mitigated by modularization, the number of modules (e.g., line-replaceable units) can still be large enough to pose a challenge of developing a coordinated maintenance policy that accounts for the coupling among individual maintenance schedules for each module. This paper focuses on opportunistic maintenance, induced failure, and other coupling mechanisms caused by competing risk phenomena. Modeling the maintenance process of an individual module or component, even if it includes modern condition-based considerations, can be described by a relatively small number of distinct states. In contrast, creating a system-level model that captures all relevant coupling leads to a state-space explosion; an implementation of such models is either very expensive or not feasible at all. To address this issue, the present paper explores the idea of developing component-level models that incorporate the aggregate effects of other components by providing a compact statistical representation of the combined influence on a given component of all other system components. This approach is somewhat analogous to the mean-field theory used in physics to avoid explicit description of pair-wise interactions. An analytical method based on asymptotic considerations is developed for combining the effects of multiple components into a single Weibull distribution (inspection intervals are assumed to be smaller than the failure scale). The accuracy of this approach is demonstrated by successfully representing the combined effect of two competing Weibull distributions as well as the combined effect of two competing lognormal distributions. In particular, it is shown that the proposed method provides a superior match for the combined distribution in the relevant time range as compared to standard methods of approximating a distribution (e.g., matching moments or using the maximum likelihood estimate). The accuracy of representing opportunities using exponential distributions is explored as well.
A global router using an efficient approximate multicommodity multiterminal flow algorithm

The global routing problem is formulated as a multiterminal, multicommodity flow problem with integer flows. An epsilon bound 2-terminal multicommodity flow algorithm with fractional flows is adapted to handle multiterminal commodities. We show that under certain conditions, our approach derives an approximate optimal solution. The experimental results with benchmark data are quite promising.
Wide-area differential GPS reference-station placement

A wide-area differential Global Positioning System (GPS) augmentation system provides differential corrections to GPS users in a large, but bounded, service area. Wide-area differential corrections are of two basic types: satellite-ephemeris/clock corrections and ionospheric-delay corrections. The underlying differences between the two types of corrections and the measurements used to calculate them impose different requirements on the placement density of the reference stations. There are also unique placement requirements near the boundaries of the service area. This paper presents guidelines for reference-station placement to provide the required navigation accuracies for aviation precision approach and other navigation modes of flight. The differential-correction accuracies for various reference-station placements are analyzed. The computer modeling tool used to verify and illustrate placement principles is Rockwell's Satellite-Based Air Traffic Management Accuracy Performance Model (SAPM).
RIGOR IN BEHAVIORAL EXPERIMENTS: A BASIC PRIMER FOR SUPPLY CHAIN MANAGEMENT RESEARCHERS

The study of the nuances of human behavior in supply chain management (SCM) contexts and the behavioral reactions that accompany changes in operating policies has finally started to gain a strong headwind. This has come after several decades of operational modeling in which the behavior of the human actors, so critical to the mechanics of operating policies, has either been largely simplified or ignored. With the growth in joint work in experimental behavioral testing and improvements in behavioral codification, greater insight into the practicality of operational policies is now emerging. Yet in order to ensure such practicality, the rigor of this new joint experimentation needs to be ensured. While SCM researchers have a rich history in the rigor of artificial modeling, the sparse history of behavioral experimentation in SCM provides much less evidence of an understanding of what “rigor” with such methods entails. The purpose of this brief essay is to touch on some of the basic tenets of rigorous behavioral experimentation, and to hopefully promote such rigor in future SCM behavioral studies.
Paleomagnetic evidence for long‐term (104 year) Memory and periodic behavior in the Earth's core dynamo process

A new paleomagnetic secular variation (PSV) record from the late Quaternary Wilson Creek beds of Mono Lake, California contains a distinctive periodic vector waveform that follows and is almost certainly related to the Mono Lake excursion. A comparison of all published PSV results from the Wilson Creek beds suggests that the magnetic field at Mono Lake went through an interval (36,000-28,000 ybp) of very low amplitude PSV followed by the Mono Lake excursion (28,000-27,000 ybp) and four subsequent recurrences (27,000-12,500 ybp) of the excursion waveform with relatively diminished amplitudes (lower than the excursion amplitude but higher than PSV amplitudes at Mono Lake since 12,500 ybp). This pattern clearly suggests that the Mono Lake excursion is related to ‘typical’ PSV; it also suggests that the core dynamo process responsible for PSV is capable of near impulse onset, persistence over a time scale of 15,000 years, and quasi-periodic behavior that is non-wave-length dispersive in time.
Lessons learned from exploratory research about viral hepatitis

The Centers for Disease Control and Prevention conducted exploratory research as part of planning a national education campaign to raise awareness about viral hepatitis in the United States. The purpose of this qualitative research was to assess the baseline knowledge, attitudes, and screening behaviors of four population groups. Sixteen focus groups were conducted during a 6-week period in the fall of 2009, with a total of 119 adults aged 35 to 60 years in Boston, Massachusetts; Chicago, Illinois; and Houston, Texas. The groups were stratified by Asian Americans, African Americans, gay or bisexual men, and general population. Group size ranged from three to nine participants, and each session was approximately 90 minutes in length. Both awareness and knowledge of viral hepatitis were low among all participants, including those at increased risk for the disease. Little was known about the different types of hepatitis, risk factors, or how the viruses are transmitted. Regarding the last, many indicated that the disease was airborne. In addition, participants incorrectly assumed that if they had viral hepatitis, they would have symptoms and know they were infected. Many participants also believed that they had been tested for the disease since their health care providers routinely "test their blood." The findings indicate that significant and concerted educational efforts are needed to improve basic knowledge of viral hepatitis, as well as knowledge about transmission, risk factors, screening, and treatment. As a result, a general awareness and education campaign must precede and support efforts to encourage screening.
Multiple Source Detection and Localization in Advection-Diffusion Processes Using Wireless Sensor Networks

This paper concerns the use of large-scale wireless sensor networks to detect and locate leaks of specified gases in the presence of time-varying advection (air currents) and diffusion. We show that when leaks are rare but constant for long periods, Kalman filtering combined with binary hypothesis testing provides an effective alternative to full-scale hypothesis testing covering all possible combinations of leaks and leak intensities. To reduce energy consumption and use of communication bandwidth, a two-tiered strategy is proposed in which a reduced number of sensors (Tier 1) provides coarse-grid sensing. When a leak is detected by the Tier 1 strategy, fine-grained grids of sensors (Tier 2) are activated around the vicinities of the detected leak areas to provide more precise detection and localization. Energy consumption is further reduced by applying an information versus energy-based dynamic sensor selection technique. Details of a laboratory implementation are presented and simulation results illustrate the approach and demonstrate its effectiveness.
Trans* Individuals’ Experiences of Gendered Language with Health Care Providers: Recommendations for Practitioners

This study highlights the experiences of trans ∗ individuals in regard to the use of gendered language by their medical providers. A total of 20 individual interviews were conducted with trans ∗ -identified individuals. Thematic analysis was used to analyze participants' responses. Participants discussed both positive and negative experiences with gendered language in a health care setting. Four primary themes emerged through their experiences that were then used to develop recommendations for providers interested in improving the health care of trans ∗ individuals: (a) medical forms; (b) insurance sex versus gender identity; (c) binary language; and (d) whole person, well-being care.
Every Good Regulator of a System Must Be a Model of That System

Today, as a step towards the control of complex dynamic systems, models are being used ubiquitously. Being modelled, for instance, are the air traffic flows around New York, the endocrine balances of the pregnant sheep, and the flows of money among the banking centres.
Characterizing the failure processes that limit the storage of energy in carbon nanotube springs under tension

We report measurements of the mechanical properties and energy storage capabilities of carbon nanotube (CNT) springs under tensile loading, including correlated measurements of their cyclic loading and electrical resistance behavior. Tests are conducted on fibers of multi-walled CNTs fabricated from 6 mm tall forests. The highest measured strength and stiffness of the fibers are 2 N tex−1 and 70 N tex−1 respectively. The highest recorded energy density is approximately 7 kJ kg−1 or 500 kJ m−3, more than an order of magnitude higher than the gravimetric energy density of steel springs, and half the volumetric energy density of steel springs. The resistance and stress responses of the fibers during loading to failure and cyclic loading demonstrate that disorder at the nanoscale affects the bulk response. CNT springs show limited effects of fatigue under 75 tensile cyclic loading cycles. Improving the structural quality of the CNTs and the organization of the fibers offers potential to significantly increase the energy storage capacity of the springs.
Association of In Vitro Fertilization with Beckwith-Wiedemann Syndrome and Epigenetic Alterations of LIT1 and H19

Recent data in humans and animals suggest that assisted reproductive technology (ART) might affect the epigenetics of early embryogenesis and might cause birth defects. We report the first evidence, to our knowledge, that ART is associated with a human overgrowth syndrome—namely, Beckwith-Wiedemann syndrome (BWS). In a prospective study, the prevalence of ART was 4.6% (3 of 65), versus the background rate of 0.8% in the United States. A total of seven children with BWS were born after ART—five of whom were conceived after intracytoplasmic sperm injection. Molecular studies of six of the children indicate that five of the six have specific epigenetic alterations associated with BWS—four at LIT1 and one at both LIT1 and H19. We discuss the implications of our finding that ART is associated with human overgrowth, similar to the large offspring syndrome reported in ruminants.
Associations between friends' disordered eating and muscle-enhancing behaviors.

Dieting, unhealthy weight control and muscle-enhancing behaviors are common among adolescents: friends are a probable source of influence on these behaviors. The present study uses data provided by nominated friends to examine associations between friends' disordered eating and muscle-enhancing behaviors and participants' own behaviors in a diverse sample of American youth. Male and female adolescents (mean age = 14.4) completed surveys and identified their friends from a class roster; friends' survey data were then linked to each participant. Participants (N = 2126) who had at least one nominated friend were included in the analytic sample. Independent variables were created using the same weight control and muscle-enhancing behaviors reported by nominated friends, and were used in logistic regression models to test associations between participants' and their friends' behaviors, stratified by gender. Results indicated that dieting, disordered eating and muscle-enhancing behaviors were common in this sample, and selected friends' behaviors were associated with the same behaviors in participants. For example, girls whose friends reported extreme weight control behaviors had significantly greater odds of using these behaviors than girls whose friends did not report these same behaviors (OR = 2.39). This research suggests that friends' weight- and shape-related behaviors are a feature of social relationships, and is the first report demonstrating these associations for muscle-enhancing behaviors. Capitalizing on the social element may be important to the development of increasingly effective intervention and prevention programs.
Medical Student Wellness: An Essential Role for Mentors

Medical students experience significant stress and have high rates of depression and anxiety. Medical schools should have systems in place to identify these students and should have adequate resources available to support these students in obtaining professional assistance. One approach in promoting medical student wellness is to train faculty who have longitudinal relationships with medical students in the identification and triage of students in distress. We describe a learning community of faculty (with longitudinal relationships with students) in the Stanford University School of Medicine (SUSoM), Educators for CARE (E4C), which has served as a valuable resource to promote medical student wellness. In addition to the role learning communities have in promoting teaching and mentoring in medical schools, these programs can have a valuable role in promoting medical student wellness. Research is needed to determine the most effective ways medical schools can promote and maintain medical student well-being during the challenging time of medical training.
Nutritional interventions for treatment of seasonal affective disorder.

There is a need for further investigation of the effects of carbohydrate consumption as an alternative treatment for seasonal affective disorder
Spatially explicit micro-level modelling of land use change at the rural–urban interface

Abstract This paper describes micro-economic models of land use change applicable to the rural–urban interface in the US. Use of a spatially explicit micro-level modelling approach permits the analysis of regional patterns of land use as the aggregate outcomes of many, disparate individual land use decisions distributed across space. In contrast to the models featured by Nelson and Geoghegan, we focus on models that require spatially articulated data on parcel-level land use changes through time. In characterising the spatially disaggregated models, we highlight issues uniquely related to the management and generation of spatial data and the estimation of micro-level spatial models.