cssi/SciSciGPT-SciSciNet huggingface dataset:
On Michell trusses

Abstract A modification of Michell's problem1 is formulated. This concerns the minimum-weight design of a truss T that transmits a given load to a given rigid foundation with the requirement that the axial stresses in the bars of the truss stay within an allowable range. It is then shown that the truss T cannot be less stiff in the elastic range or in stationary creep than any other truss that uses the same amount of material and respects the same allowable range of axial stress. Finally, it is shown that a truss of minimum weight that supports given point masses from the given rigid foundation and has a given fundamental natural frequency has the same layout as the truss T but, in general, different cross-sectional areas.
Rates of OH radical reactions. The reaction OH + SO2 + N2

Abstract Absolute rate constants for the reaction OH + SO2 + N2 have been determined in the gas phase, at 297 K, in the pressure range 50–760 Torr. OH radicals were generated by flash photolysis of N2O/H2 mixtures and were monitored by time-resolved resonance absorption. The second-order rate constant kII was found to depend on the pressure of N2 and may be expressed as: kII=7.4 × 1011/(1 + 237/P)where P is in Torr and kII in cm3 mol−1s−1.
Use of a Photodensitometric Technique to Quantify Microscopic Lung Lesions in Mice: Antiviral Activity Against Swine Influenza Virus

Abstract During studies of swine influenza virus (A/NJ/76) infection, a technique was devised to quantify the pulmonary lesions in infected mice treated at different time intervals with antiviral chemotherapeutic agents. The technique is based on the premise that as the severity of microscopic change increases, the optical density of lung sections also increases because of edema and increased cell numbers in infected lungs. Seven days after intranasal instillation of the virus, mice were killed and the lungs were perfused with 2% glutaraldehyde at constant pressure. Lungs were processed in a routine manner, sectioned at standard levels, and stained with hematoxylin and eosin. By using standard photomicrography equipment, multiple optical density measurements were made of lung sections in a carefully controlled systematic manner, and a mean optical density was determined for each lung. The optical density of lungs of mice treated before and after infection with amantadine, rimantadine, or ribavirin was significantly reduced compared with that of the lungs of infected, untreated controls. If treatment was delayed until 15 h after infection, amantadine and ribavirin were effective in reducing pulmonary optical density, but rimantadine was without effect. These findings correlated well with mean lung weight of each group; however, the sensitivity of the optical density technique was greater. Subjective scoring of microscopic lesions revealed differences only between infected and uninfected controls. The densitometric method offers promise as a reliable means of objectively quantifying the pulmonary response to a variety of infectious, toxic, and therapeutic agents.
Liposomes for the transport of an impermeable fluorescent dye into muscle fibers.

Abstract Positively charged liposomes were prepared by the method described by Deamer (BBA 443:629, 1976). A fluorescent dye, 1,5-IAEDANS, which binds covalently to protein thiols was captured in these liposomes and transported in frog semitendinous muscle fibers. Sodium dodecylsulfate polyacrylamide gel electrophoresis of these muscle fibers revealed that the contractile protein actin was predominantly stained with the fluorescent dye. In contrast, muscle bundles incubated in Ringers solution containing only free dye showed no fluorescence on the gels. Also, the liposome suspension did not alter the excitability of the muscle fibers. Thus, artificial liposomes of the composition described here, can be used effectively to transport nonpenetrating molecules into muscle fibers without any adverse effects on their excitability.
The Effects of Clinical Workload on Teaching in the Emergency Department

Abstract Background: Academic emergency physicians have expressed concern that increased clinical workloadand overcrowding adversely affect clinical teaching.Objectives: To evaluate the inﬂuence of clinical workload and attending physicians’ teaching characteris-tics on clinical teaching in the emergency department (ED).Methods: This was a prospective observational study using learner satisfaction assessment tools to evalu-ate bedside teaching. On days when a research assistant was available, all ED residents and attending phy-sicians were queried. A total of 335 resident surveys were administered over nine months (89% response).Clinical workload was measured by perception and patient volume. Teaching quality and characteristicswere rated on ten-point scales. A linear mixed-effects model was used to obtain adjusted impact estimatesof clinical workload and teaching attributes on teaching scores while controlling for individual attendingphysicians’ teaching ability and residents’ grading tendencies.Results: No clinical workload parameter had a signiﬁcant effect on teaching scores: residents’ workloadperception (b estimate, 0.024; p = 0.55), attending physicians’ workload perception (b estimate, 0.05; p =0.28), patient volume in patients per hour (b estimate, 0.010; p = 0.36), and shift type (b estimate, 0.19;p = 0.28). The individual attending physician effect was signiﬁcant (p < 0.001) and adjusted in each case.In another model, the attending physicians’ learning environment established (b estimate, 0.12; p =0.005), clinical teaching skills (b estimate, 0.36; p < 0.001), willingness to teach (b estimate, 0.25; p <0.001), and interpersonal skills (b estimate, 0.19; p < 0.001) affected teaching scores, but the attendingphysicians’ availability to teach had no signiﬁcant effect (b estimate, 0.007; p = 0.35).Conclusions: Clinical workload and attending physicians’ availability had little effect on teaching scores.Attending physicians’ clinical teaching skills, willingness to teach, interpersonal skills, and learning envi-ronment established were the important determinants of overall scores. Skilled instructors received higherscores, regardless of how busy they were.ACADEMIC EMERGENCY MEDICINE 2007; 14:526–531 a 2007 by the Society for Academic EmergencyMedicineKeywords: education, medical training, workload, crowding, teaching
A shear test method to measure shear strength of metallic materials and solder joints using small specimens

The asymmetrical four-point bend (AFPB) shear test, which is the subject of this paper, was originally developed by Slepetz et al. to evaluate the shear properties of large metallic specimens and polymer composites. Similar to the Iosipescu test, the AFPB test also provides a nearly pure-shear stress state with an unnotched specimen. However, since the AFPB test involves point loading as opposed to distributed surface loading in the case of the Iosipescu test, the shear force generated in this method depends on the fixture dimensions. Therefore, its use has been very limited. Recently, it was shown that this method could be used to evaluate high temperature shear properties of small ceramic composite joints. Thus, as an extension to the earlier aforementioned work, the goal of this study was to investigate the application of AFPB test method to small metallic test specimens. In this work, the Iosipescu shear test was also used to check the accuracy of results from the AFPB tests. The stress analysis of this test method by finite element modeling (FEM) will be published elsewhere.
The Ethnomedicinal Uses of Magnoliaceae from the Southeastern United States as Leads in Drug Discovery

In Asia and North America, members of the family Magnoliaceae have been and are presently used extensively in indigenous herbal medicine. Many taxa of the genus Magnolia produce lignans and sesquiterpene lactones, some with considerable in vitro bioactivities. This review focuses on selected natural products of the genus Magnolia from the southeastern United States with demonstrated biological and pharmacological properties. Ethnomedicinal data obtained from the Native Americans of the southeastern United States correlate well with the results of pharmacological investigations.
INTERNATIONAL EXPERIENCE THEORY AND GLOBAL STRATEGY

A full understanding of the economic development processes of the Newly Industrialised Countries (NICs) is important both for the multinational corporations and the developing countries. This paper suggests a theoretical framework based on experience theory to explain how the NICs obtained their strategic comparative advantages in global markets. It is argued that the world social and economic environment of the post‐World War II period was conducive for the realisation of such advantages. Most recent changes, however, have important implications for both the developing countries and the multinational corporations in the selection of global strategies.
Multiple cytogenetically abnormal clones in two polycythemia vera patients

Multiple abnormal karyotypes representing apparently unrelated clones were observed in initial bone marrow samples from two polycythemia vera patients. Serial sampling demonstrated a selective advantage in proliferation of one clone over the others. The predominance of the single clone was associated with progression of the disease.
The Promise of Digital History in the Teaching of Local History

oo often, students do not share their teacher's passion for history. It is easy to understand why some students dread history classes; all one has to do is sit through a poorly delivered high school history lecture or read a typical history textbook. History frequently is taught as a set of facts that must be memorized to either pass a test or become culturally literate (Whelan 1997). Such an approach to history instruction reduces content to a consumable, socially irrelevant product and strips meaning from the classroom. When history is delivered as a product, students often are unable to make connections, develop sustainable interests, or establish relevance (Seixas 1994; Grant 2001). Student interest is best generated when the answer to the ageold question, "Why do I need to know this?" is relevant to their lives. To alleviate the drudgery of typical history instruction, teachers can design activities that enable students to use authentic historical resources to pull engaging, meaningful, and useful content from the past. One of the best approaches to learning about the usefulness of the past is through the study of local history. Such study could focus on constructing public historical resources and re-constructing personalized stories of the past (Coles and Welch 2002). In an effort to construct more meaningful history experiences for students, we developed a local history class for high school students. The class focused on the history of Cherokee County, Georgia, and is part of a larger Cherokee County Digital History Project (2003), which helps students construct their own knowledge about local history by connecting them to their community. In addition to the class, we developed two online, local historical resources that highlight people and topical themes in Cherokee County. High school students worked in conjunction with social studies preservice education students at Georgia State University to develop these resources. In this article, we argue in favor of introducing local history in high school classes. We discuss the rationale for local history, using the local history course we recently developed as an example. In addition, we consider how technology enables the implementation of local history into this specific course, as well as school curricula in general.
Upgrading low-quality natural gas with H2S- and CO2-selective polymer membranes: Part I. Process design and economics of membrane stages without recycle streams

Abstract The upgrading of low-quality natural gas by membrane separation processes utilizing two different types of polymer membranes was investigated by process design, optimization, and economic assessment studies. The membranes considered for these processes exhibit high CO 2 /CH 4 and H 2 S/CH 4 selectivities, respectively. Low-quality natural gas was simulated by ternary CH 4 /CO 2 /H 2 S mixtures containing up to 40 mol% CO 2 and 10 mol% H 2 S. The membrane processes were designed to reduce the concentrations of CO 2 and H 2 S in the natural gas to US pipeline specifications (≤2 mol% CO 2 and ≤4 ppm H 2 S). This study has identified the membrane process configurations (single stage or two stages connected in series) and types of membranes (CO 2 -selective, H 2 S-selective, or both) that would yield the most economical processes for the upgrading of natural gas containing different ranges of CO 2 and H 2 S concentrations. The upgrading costs of process configurations without recycle streams are dominated by the cost of CH 4 lost in the permeate stream. The effects of recycle streams, variations in feed flow rate and pressure, membrane module cost, and wellhead cost of natural gas on the upgrading costs will be reported elsewhere.
Playful Dialogues of a Bilingual Child in Everyday Conversations: Foundations of Early Literacy

Many young children of Mexican heritage enter U.S. schools with knowledge of two language systems and emergent biliterate abilities. Bilingualism in young children may go unnoticed when instructional practices favor English. This case study describes how Lucia’s bilingualism and emergent biliteracy parallel competencies essential to literacy development. The language samples highlight the influence of adult-mediation interactions in everyday conversations as well as during playful dialogues, characterized by the incorporation of fantasy and symbolic play. The findings show how adult-mediated dialogues challenged the young bilingual to engage her metacognitive and metalinguistic awareness when positioned to meet communicative goals and to solve conceptual conflicts, both verbal and written. These opportunities guided the young child to also critically think about language and to expand her notions about literacy. We draw implications about how educators can leverage these metacognitive and metalinguistic c...
Recovery of erythropoietin from anemic sheep plasma.

A method is described for the large-scale preparation of erythropoietin from anemic sheep plasma. DEAE-cellulose and carboxymethylcellulose column chromatography was used to prepare Step II erythropoietin. A total of 168 sheep yielded 499 liters of plasma from which 323,000 IU of Step II erythropoietin was obtained.
A RETAINED URETERAL STUMP WITH CALCULI

Augmentation cystoplasty is a commonly used method to treat patients with inadequate bladder capacity. Calculus formation within the altered urinary tract has been a frequent complication. We report the unique finding of calculi within a retained ureteral stump in a patient who had undergone enterocystoplasty. CASE REPORT A 29-year-old female presented with recurrent urinary tract infections that were refractory to treatment. The patient had been born with sacral agenesis and imperforate anus. Neurogenic bladder and vesicoureteral reflux had subsequently developed, and the patient underwent ileal conduit formation for management of progressive bilateral hydroureteronephrosis as a young child. At age 15 years she underwent urinary undiversion with ileocecoplasty to the native bladder. Videourodynamics were repeated at age 28 years and revealed a volume capacity of 700 ml., and bilateral grade V vesicoureteral reflux and reflux into the retained ureteral stumps. The patient performed clean intermittent catheterization every 2 to 4 hours to minimize the post-void residual urine volume. Recurrent urinary tract infections were managed with outpatient oral antibiotic therapy. In addition, in 1999 a bladder calculus had developed in the bowel segment of the bladder. The stone was managed with cystolithotripsy, with complete stone removal. In 2001 urinary tract infections recurred despite appropriate antibiotic coverage for each recurrent infection and antibiotic prophylaxis. Symptoms consisted of painful urethral catheterizations, small urethral catheterized volumes and pyuria. Plain x-ray of the kidneys, ureters and bladder demonstrated multiple calcified densities in the pelvis (see figure). In preparation for cystolithotripsy, cystoscopy of the native and augmented bladder was performed, which showed an absence of bladder calculi. However, a dilated and patulous right ureteral orifice was identified. Retrograde ureterogram revealed several filling defects in the right ureteral stump that correlated with the calcifications seen on x-ray. The ureteral stump measured approximately 8 cm. The calculi were fragmented via semirigid ureteroscopy with holmium laser lithotripsy and basket stone extraction. The bladder was copiously irrigated. The patient was discharged home on the same day with postoperative instructions to perform bladder irrigation twice daily in addition to clean intermittent catheterization. Stone analysis demonstrated calcium phosphate. DISCUSSION
The vacuferm process: A new approach to fermentation alcohol

A Vacuferm process is envisaged in which full-strength clarified molasses is fed continuously to the fermentor - still along with a recycled cell cream of aerobically grown yeast. The yeast would then need no added sterols or oleic acid. Since it is probably impractical to use an expensive vacuum fermentor to remove the last traces of sugar and alcohol from spent beer, the latter could be aerated at atmosphere pressure to provide additional yeast growth. After centrifuging, a portion of the aerated yeast cream could be returned to the fermentor as continuous inocolum; the remainder would be dried for sale as an animal feed. Alternatively, use of a crude nutritional supplement, such as wheat germ oil, would make it unnecessary to install a separate aerobic cell propagator. An obvious process improvement would be to use thermotolerant yeasts that can ferment at >45/sup 0/. Their use would permit higher pressures in the fermentor. The heat of fermentation in this process is used directly for distilling off alcohol, unlike the conventional process where it must be removed with cooling water. This saving in energy represents about 7% of the latent heat required for distilling off the alcohol. However, in the Vacuferm processmore » a 3-fold higher sugar concentration can be fermented in only 1/3 more time needed in a conventional process.« less
Kinetics of unfolding of dogfish muscle lactate dehydrogenase in the presence of guanidine hydrochloride.

Abstract Dogfish muscle lactate dehydrogenase was found to contain 7.0 (± 0.2) sulfhydryl groups per polypeptide chain (35,000 mol.-wt), of which 1.9 (± 0.2) are free to react with 5,5′-dithiobis(2-nitrobenzoic acid) in the native enzyme. The reaction of the five “masked” sulfhydryl groups with this reagent has been used to measure the rate of unfolding of lactate dehydrogenase as a function of guanidine hydrochloride concentration. The results are compatible with a one-step denaturation process involving a transition between native and completely unfolded molecules without the accumulation of stable intermediates.
Behavior of unstable atoms in applied fields

The leading radiative corrections to the behavior of atoms in time-dependent electromagnetic fields are considered. The results are expressed in closed form for the resonant measurement of the Lamb shift and fine structure of the n=2 levels of hydrogen.
Sources of control over schedule-induced drinking produced by second-order schedules of reinforcement

Abstract In Experiment 1, schedule-induced polydipsia was studied in rats reinforced by both simple and second-order fixed-interval 1 min schedules while session length, position of the drinking tube, and magnitude of the pellet reward were varied. Pellet-induced drinking decreased with successive transitions from simple to second-order schdules; however, drinking did not follow stimuli associated with pellet delivery until the reward magnitude was raised from 1 to 5 pellets. Neither session length nor tube position affected drinking. Poststimulus drinking received closer analysis in Experiment 2, where tandem, nonpaired and delayed or simultaneous paired brief stimulus second-order schedules, which were either fixed or variable, assigned large pellet magnitudes to rats. No evidence of adjunctive, stimulus-induced drinking was found. Occasions of drinking during poststimulus intervals were classified as either resumption of postpellet drinking or as low-rate terminal behavior which was unaffected by pairing relations between stimuli and pellets or by schedule class. No support was found for either discriminative or conditioned stimulus interpretations of schedule-induced polydipsia.
STRUCTURE OF THE REYNOLDS STRESS NEAR THE WALL

Experimental studies of the flow field near the wall in a turbulent boundary layer using hot-wire probes are reported. Measurements of the product uv are studied using the technique of conditional sampling with a large digital computer to single out special events (bursting) when large contributions to turbulent energy and Reynolds stress occur. The criterion used to determine when the product uv is sampled is that the streamwise velocity at the edge of the sublayer should have attained a certain value. With this simple criterion we find that 60% of the contribution to is made during only 55% of the total time.
Inflammation: sustaining the balance to optimize recovery of skeletal muscle, connective tissue, and exertional injuries.

inflammation has been described as part of the healing process since Hippocrates in ancient Greece ([5][1]). Inflammatory responses are initiated immediately after tissue damage to protect the organism, but a hyperactive inflammatory response may attack healthy tissues. In such situations, anti-
Piriformis syndrome: a real pain in the buttock?

OBJECTIVE: Herein, we provide an unbiased review of piriformis syndrome (PS), a highly controversial syndrome for which no consensus exists regarding diagnostic criteria or pathophysiology. METHODS: A review of the literature in the English language. RESULTS: A nonpartisan review of the medical literature pertaining to PS revealed that the existence of this entity remains controversial. There is no definitive proof of its existence despite reported series with large numbers of patients. CONCLUSION: PS remains a controversial diagnosis for sciatic pain. The debate regarding the clinical significance of PS remains active. Nonetheless, there may be a subset of patients in whom the piriformis muscle is a source of pain. The syndrome should be considered in the differential diagnosis of patients with unilateral lower extremity pain.
Embedded curve boundary method for micromagnetic simulations

Abstract The physical and numerical difficulties associated with inadequate boundary resolution in finite differencing applications is alleviated by the embedded curve boundary (ECB) method. The use of this technique in three-dimensional micromagnetic simulations shows more realistic boundary effects on smooth non-rectangular objects without increasing mesh resolution or computational requirements. Results of the new algorithm are presented that show the effect of smooth boundaries on magnetization field determination. A comparison of converged results with other published micromagnetic algorithms are shown for a model reference problem. Additionally, the hysteretic response of submicron-scale cobalt structures is compared with experimental measurements demonstrating the utility of the approach.
Coastline complexity: a parameter for functional classification of coastal environments

Abstract To understand the role of the world's coastal zone (CZ) in global biogeochemical fluxes (particularly those of carbon, nitrogen, phosphorus, and sediments) we must generalise from a limited number of observations associated with a few well-studied coastal systems to the global scale. Global generalisation must be based on globally available data and on robust techniques for classification and upscaling. These requirements impose severe constraints on the set of variables that can be used to extract information about local CZ functions such as advective and metabolic fluxes, and differences resulting from changes in biotic communities. Coastal complexity (plan-view tortuosity of the coastline) is a potentially useful parameter, since it interacts strongly with both marine and terrestrial forcing functions to determine coastal energy regimes and water residence times, and since ‘open’ vs. ‘sheltered’ categories are important components of most coastal habitat classification schemes. This study employs the World Vector Shoreline (WVS) dataset, originally developed at a scale of 1:250 000. Coastline complexity measures are generated using a modification of the Angle Measurement Technique (AMT), in which the basic measurement is the angle between two lines of specified length drawn from a selected point to the closest points of intersection with the coastline. Repetition of these measurements for different lengths at the same point yields a distribution of angles descriptive of the extent and scale of complexity in the vicinity of that point; repetition of the process at different points on the coast provides a basis for comparing both the extent and the characteristic scale of coastline variation along different reaches of the coast. The coast of northwestern Mexico (Baja California and the Gulf of California) was used as a case study for initial development and testing of the method. The characteristic angle distribution plots generated by the AMT analysis were clustered using loiczview , a high dimensionality clustering routine developed for large-scale coastal classification studies. The results show distinctive differences in coastal environments that have the potential for interpretation in terms of both biotic and hydrogeochemical environments, and that can be related to the resolution limits and uncertainties of the shoreline data used. These objective, quantitative measures of coastal complexity as a function of scale can be further developed and combined with other data sets to provide a key component of functional classification of coastal environments.
Generation of sequence diversity in the kinetoplast DNA minicircles of Leishmania mexicana amazonensis

Abstract In order to understand the mechanisms which generate minicircle sequence diversity, we sequenced three minicircles belonging to the same or closely related sequence classes from the kinetoplast DNA of Leishmania mexicana amazonensis strains, PH8. Raimundo, and Josefa. Closely related minicircles from PH8 and Raimundo were unexpectedly found to differ at 11% of positions within the evolutionarily conserved region, but at only 3.9% of positions in the variable region. It thus appears that accumulation of point mutations will not account for the wide intra-strain and intra-subspecies divergence of the variable region. Comparison of more distantly related minicircles from PH8 and Josefa revealed only two short stretches of 70% homology within the variable region. These stretches of homology are not located in the same positions relative to the conserved regions in their respective minicircles. They may represent vestiges of recombinational events responsible for the rapid divergence of minicircle variable regions.
Cardiac CT Artifact Mitigation through Decomposition-Based Image Reconstruction

A common problem arising in medical imaging is the suppression of undesired image artifacts with the simultaneous preservation of salient clinical information. Often the proposed processing "cure" introduces its own artifacts in other parts of the image that confound reliable diagnosis. A canonical example is the suppression of artifacts from hyperdense objects, such as metal and calcium. In this paper we propose a new decomposition-based approach to the combined image formation and the suppression of localized image artifacts which is motivated by recent results on image inpainting. The approach, which we term Model-Based Algebraic Iteration (MBAI) processing, decomposes an image into a collection of homogeneous components, each of which can be reconstructed in the manner most appropriate to its underlying nature. Because each component is localized, the effects of processing on that component do not contaminate other areas of the image. Our specific motivation is the mitigation of artifacts in cardiac multi-detector computed tomography (MDCT) images. Recently, MDCT has offered the promise of a non-invasive alternative to invasive coronary angiography to evaluate coronary artery disease. An impediment preventing its utilization as a routine clinical replacement for angiography is the presence of image "blooming" artifacts due to the presence vascular calcium. We develop MBAI for the purpose of ameliorating artifacts in cardiac images and thus increase the applicability of MDCT for the evaluation of at-risk patient population. We demonstrate preliminary results in the reduction of the calcium blooming-effect in software simulation, phantom, ex-vivo, and in-vivo MDCT data.
The role of alkanethiol spacers in a metal surface-based label-free DNA detection system

We have been developing an array-based DNA biosensor, in which DNA oligonucleotides are readily immobilized onto Au surfaces via terminal thiol groups to serve as probes for the detection of oligonucleotides in solution. One common strategy to minimize steric effects and non-specific oligonucleotide-surface interactions derived from a high surface probe density employs thiol molecules as spacers. In this study, we tested nine different alkanethiol molecules with the goal of identifying a relationship between the chemical structure of each molecule and its performance as a spacer molecule. Among the nine different spacers, 4-mercapto-1-butanol and 1-decanethiol were found to yield the optimal performance as spacers, while spacers with a bulky tert-butyl group or a ring structure (2-methyl-2-propanethiol, cyclohexyl mercaptan and thiophenol) yielded poorer performance. Spacers with a short, branched carbon chain (1- mercapto-2-propanol and 3-mercapto-1,2-propanediol) provided an intermediate performance. These results suggest that DNA sensor response is highly sensitive to the chemical structure of the alkanethiol molecules that are employed as spacer molecules.
Liver disease in aids

Abnormal liver chemistries, unexplained fevers, or hepatomegaly prompted 36 liver biopsies on 34 patients with the acquired immunodeficiency syn-drome. The most common finding was the presence of hepatic granulomas, seen in 13 of the biopsy specimens. Eight of these granulomas were illdefined, and 5 were more clearly associated with mycobacterial disesse. Portal fibrosis and fatty infiltration were comon, but a paucity of significant inflammatory activity was seen despite elevated aspartate aminotransferase levels, perhaps related to the underlying imunoincompetent status. Other noteworthy histopathologic findings included 1 patient each with peliosis hepatitis and cryptococcal hepatitis. Electron-microscopic evidence of cytoplasmic tubular structures or viral particles were seen within the hepatocytes of 2 patients. It is concluded that a broad spectrum of hepatic histopathology may be seen in the acquired immunodeficiency syndrome, and that liver biopsy may be diagnostically valuable in the clincial investigation of such patients.
Effects of petrolatum on stratum corneum structure and function

Background: Ointments (e.g., petrolatum) are thought to be occlusive, thereby blocking transcutaneous water loss and trapping water under the skin's surface. If this premise is correct, then petrolatum should delay barrier recovery after barrier perturbation, as shown previously in occluded murine skin. Objective: We reexamined the assumption that Vaseline Petroleum Jelly (VPJ) is occlusive, ascertaining both its site and mechanism of action. Methods: Barrier recovery was measured in VPJ-treated versus untreated sites after acetone-induced barrier disruption in human volunteers. Moreover, VPJ was localized within the stratum corneum (SC) with tracers and ruthenium tetroxide staining, which allowed visualization of the depth of VPJ penetration and its relation to intercellular membrane structures. Results: VPJ accelerated, rather than impeded, barrier recovery. Moreover, VPJ was present within the interstices at all levels of the SC, where it replaced intercellular bilayers. Conclusion: VPJ neither forms nor acts like an epicutaneous impermeable membrane; instead, it permeates throughout the SC interstices, allowing normal barrier recovery despite its occlusive properties.
HLA homozygosity and haplotype bias among patients with chronic lymphocytic leukemia: implications for disease control by physiological immune surveillance

HLA homozygosity and haplotype bias among patients with chronic lymphocytic leukemia: implications for disease control by physiological immune surveillance
Women Seeking Political Asylum: Negotiating Authority, Gender and a Lost Home

This article examines the multiple intersecting challenges faced by women who are survivors of politically motivated violence and are seeking political asylum in the United States. These women have a particular vulnerability to authority, face the forced telling (and unwanted revisiting) of a trauma narrative, have an ambivalent relationship with notions of home and homeland, face numerous gender related challenges, and struggle with significant post-traumatic sequelae. This paper addresses these dynamic issues and contrasts the experience of these women with that of so-called voluntary immigrants. These and other issues are explored with brief case examples, with clinical recommendations for working with this population.
Suppurative complications and upper airway obstruction in infectious mononucleosis

A 17-year-old female patient presented to the emergency department reporting having fever, sore throat, and pain with swallowing for several days. The result of her rapid strep screen was negative. She had an elevated white blood cell count, mildly elevated AST and ALT levels, and a positive result from a heterophile antibody test (BBLTM MonoslideTM). She was diagnosed with infectious mononucleosis. Given her inability to tolerate oral fluids, she was admitted to the hospital for intravenous hydration. After 3 days of receiving methylprednisolone intravenously, she had worsening throat pain, progressive neck swelling, difficulty handling her secretions, and new respiratory symptoms. During the examination, she was sitting upright in bed in moderate respiratory distress. She had kissing, exudative tonsils with palatal and uvular edema. Examination of her neck showed significantly enlarged anterior and posterior cervical lymph nodes without fluctuance. Her lung exam revealed subcostal retractions with transmitted upper airway sounds but good aeration. The edge of her liver and spleen tip were palpable. Because of the rapid progression of symptoms while on medical therapy, computed tomography (CT) of the neck was performed. Sagittal reconstructions showed adenoidal hypertrophy compromising her nasopharynx, and massive tonsillar enlargement causing nearly complete obstruction of her oropharyngeal airway (Fig. 1), with airway narrowing to less than 2.5 mm in axial images. Bilateral low-density lesions within the paratonsillar regions were suggestive of abscesses and retropharyngeal soft-tissue swelling was consistent with phlegmon (Fig. 2). The patient was taken to the operating room for an emergent tonsillectomy. Bilateral peritonsillar abscesses were drained, pus was sent for culture, and her tonsils were excised. Cultures from the abscesses grew Streptococcus milleri. The patient was discharged home 2 days later to complete a 2-week course of oral clindamycin. Most patients with infectious mononucleosis (IM) have a benign, self-limited course. However, a wide range of severe complications have been described including airway obstruction, splenic rupture, meningoencephalitis, Guillain-Barre syndrome, peritonsillar abscess, and hemolytic anemia. Upper-airway obstruction results from lymphoid hyperplasia throughout Waldeyer’s ring, with associated soft-tissue edema. As many as 25% of patients hospitalized for IM will have some degree of airway obstruction. Peritonsillar abscesses (PTAs) occur in approximately 1% of hospitalized patients with IM and may further obstruct the airway. Most commonly, peritonsil-
Application of the fourth-order anharmonic theory to the prediction of equations of state at high compressions and temperatures.

Abstract The fourth-order anharmonic theory is the extension of the ordinary theory of lattice dynamics into the regime of finite strain. Exhaustive numerical applications of the theory at high pressure are made, yielding predictions for density, temperature and elastic moduli of seventeen solids under shock compression. The theory describes well most of thed density data to compressions ΔV / V 0 )max which are generally in accord with expectation (0.30), with some notable exceptions. The data at higher shock temperatures (on initially porous samples) are considerably fewer; the theoretical predictions are generally accurate. The elastic moduli data in the shock state are fewer yet; the theory gives less satisfactory predictions. The geophysical interest in these results is that that total elasticity (density, thermal expansivty and elastic velocities) of solids under upper mantle conditions can be described within a unified theoretical framework. We cannot say at present if the theory is reliable under the conditions of the lower mantle. This uncertainty is shown to include also the predictions of the Eulerian formulation of finite strain theory.
Ecological speciation by sexual selection

Quantitative genetic models are used to investigate a mechanism of speciation involving natural and sexual selection on a population with more than one ecological niche available. Female choice of mates, based on ecologically important characters, can initiate a sudden shift into a new niche. Whether males alone or both sexes make the transition depends strongly on the genetic correlation between homologous male and female characters. This mode of speciation rapidly produces premating and postmating isolating barriers, as well as ecological separation, between populations that can then coexist in the same area as distinct species.
CHARACTERIZATION OF A LEUCINE-ZIPPER-LIKE DOMAIN IN VPR PROTEIN OF HUMAN IMMUNODEFICIENCY VIRUS TYPE 1

Abstract Human immunodeficiency virus type 1 (HIV-1) replicates productively in vitro in CD4+-T cells and/or macrophages. In the host, however, HIV-1 replication may be restricted by the quiescence of susceptible cells. Vpr is a 15-kDa late viral gene product, which is assembled in the virion and suspected to enhance HIV-1 replication in the infected host. We demonstrated previously that Vpr interacted specifically with the cellular transcription factor Spl, and activated transcription from the HIV-1 long-terminalrepeat. Both Vpr-Spl interaction and trans-activation by Vpr required a central Leu/Ile-rich domain (LR domain, aa 60–81) in Vpr. This domain of Vpr was also found critical for Vpr interaction with another cellular protein of 180 kDa. We now provide biochemical evidence that the Vpr LR-domain has a leucine-zipper-like structure. The leucine-zipper structure has been found in a variety of cellular transcription factors, which use the leucine-zipper domain to form a specific dimer before they can bind to DNA through an upstream basic domain. The LR domain of HIV-1 Vpr, when fused to the basic domain of the cellular transcription factor CREB, was capable of supporting specific DNA binding by the CREB basic domain. Point mutational analysis of the Leu/Ile residues in the LR domain suggested that multiple Leu/Ile residues may be involved in maintaining the leucine-zipper-like structure. Mutagenesis in the context of the full-length Vpr also helped identify Leu/Ile residues critical for Vpr interaction with the cellular 180-kDa protein. These results suggested that the leucine-zipper-like domain may be an important functional determinant for HIV-1 Vpr.
Autism and autism risk in siblings of children with specific language impairment.

Background: Several studies have shown that family members of children with autism have elevated rates of spoken and written speech and language problems. Aims: This study asked whether there was also a greater rate of siblings with autism among probands with specific language impairment. Methods & Procedures: The probands in this study were 158 children with specific language impairment and 132 children with normal language status. These probands had 522 siblings who were examined for risk of autism using the Autism Behavior Checklist. Siblings found to be at risk were then examined using the Autism Diagnostic Interview--Revised and the Autism Diagnostic Observation Schedule-G. Outcomes & Results: A concentration of siblings with risk for a diagnosis of autism was found in association with probands who had poor spoken language skills. Four siblings of the 522 (0.8%) met the diagnostic standards for autism. All the probands of these siblings had spoken language scores below &#109 1 SD and three had diagno...
Orientation specificity of length assimilation and contrast

The orientation specificity of length assimilation and contrast was assessed using the parallellines array. The purpose was to determine the nature of the representation of length both within and outside of the “attentive field.” Experiments 1 and 2 demonstrated that when both contextual and test lines are within an attentive field and do not intersect, the resulting simultaneous length assimilation is independent of orientation. In Experiment 3, simultaneous length contrast was produced by placing the contextual line outside of the attentive field; it also was independent of orientation. Finally, Experiment 4 demonstrated that the sequential length contrast (length aftereffect) produced by a 5-sec prior inspection of a contextual line was independent of orientation, whereas the contrast produced by 60 sec of contextual-line inspection showed some degree of orientation specificity. These results, combined with those obtained with orientation illusions (Tyler & Nakayama, 1984; Wenderoth & Johnson, 1984; Wenderoth, O’Connor, & Johnson, 1986), suggest a qualitative relationship of length and orientation coding that is characterized by partial and mutual overlap of length and orientation information.
Social referencing and caretaker expressive behavior in a day care setting

Abstract Facial expressions of 18 female day care workers were observed during their natural interactions at their day care centers. Subsequently, they participated twice in a social referencing procedure, once with each of two infants for whom they cared ( M age = 14.6 months, SD = 2.72). The procedure involved presentation of two ambiguous toys and caretaker posing of enjoyment/joy and fear/avoidance expressions. Results showed that infants approached closer to the toy after seeing an enjoyment/joy as opposed to a fear/avoidance expression. In addition, caretakers who were more expressive in their natural interactions were referenced more during the fear/avoidance episode, and their infants maintained a greater distance from the toy in response to the fear/avoidance expression. In particular, caretaker use of masked or mitigated negative expressions predicted greater avoidance of the toy in the fear/avoidance condition. Thus, social referencing behavior occurred with respect to nonmaternal caretakers and was related to caretakers' natural expressive behavior.
Elicitation of lignin peroxidase in Streptomyces lividans

Using a novel starch-based medium (DJMM) which elicits high expression of lignin peroxidase (ALiP-P3) fromStreptomyces viridosporus T7A, significant levels of ALiP-P3 (between 1135 and 1784 nmol/g cell-min) were excreted byS. lividans TK23, TK24, and TK64 with the supernatants capable of degrading dichlorophenol (these strains were previously reported to produce low levels of LiP). TheS. lividans wildtype strains produced 1/9 to 1/6 the cell-specific LiP activity previously detected inS. viridosporus T7A cultures grown in the same starch-based medium; however, by using DJMM to increase the cell density, the volumetric activity of wild-typeS. lividans TK23, TK24, and TK64 strains was increased 11 to 20-fold compared to cultivations in a yeast-extract-based medium. Consequently, this increase of LiP production allows the direct analysis of LiP activity in the supernatants of these strains without the need for enzyme concentration through ultrafiltration. Immunoblot analysis verified that a single 56.5 kDa band, secreted by all three strains, was extremely similar in size and immunologic reactivity to the 59.5 kDa ALiP-P3 isoform of S.viridosporus T7A. In addition, Western blot analysis was used to show that a previously cloned 4.1 kb chromosomal fragment ofS. viridosporus T7A DNA did not contain the ALiP-P3 structural genes.
InterState: a language and environment for expressing interface behavior

InterState is a new programming language and environment that addresses the challenges of writing and reusing user interface code. InterState represents interactive behaviors clearly and concisely using a combination of novel forms of state machines and constraints. It also introduces new language features that allow programmers to easily modularize and reuse behaviors. InterState uses a new visual notation that allows programmers to better understand and navigate their code. InterState also includes a live editor that immediately updates the running application in response to changes in the editor and vice versa to help programmers understand the state of their program. Finally, InterState can interface with code and widgets written in other languages, for example to create a user interface in InterState that communicates with a database. We evaluated the understandability of InterState's programming primitives in a comparative laboratory study. We found that participants were twice as fast at understanding and modifying GUI components when they were implemented with InterState than when they were implemented in a conventional textual event-callback style. We evaluated InterState's scalability with a series of benchmarks and example applications and found that it can scale to implement complex behaviors involving thousands of objects and constraints.
Fractal permeation characteristics of preforms used in liquid composite molding

Preform permeability plays a critical role in the analysis of mold filling during liquid composite molding processes. Because of the complex structure of the preform pore network, a quantitative description of the pore structures, and consequently, the evaluation of the permeabilities presents a major challenge. In this article, a fundamental description of the disordered preform pore structures based on fractal techniques is utilized to relate the preform permeabilities to the actual microstructures in terms of two fractal dimensions. Comparison of the fractal permeation model predictions with experimentally-measured permeabilities demonstrates excellent agreement over a wide range of fiber volume fractions, injection pressures, and isotropic and anisotropic preform architectures.