cssi/SciSciGPT-SciSciNet huggingface dataset:
DLVO interaction of colloidal particles with topographically and chemically heterogeneous surfaces

The DLVO force and potential energy of interaction between microspheres and topographically and chemically heterogeneous surfaces in aqueous solution are computed using a modification of the surface element integration approach. The heterogeneous surface has an array of cylindrical pillars of varying height, diameter, and arrangement to model different nano-topographies. In agreement with previous studies, the nano-topography decreases the size of the potential energy barrier for unfavorable surfaces because the pillars limit the minimum separation distance. The influence of topography is significant even for pillars several nanometers high and is more pronounced if the surface potential of the pillar tops differs from that of the underlying surface. A new force- and energy-averaging model is introduced as a simple method to compute the mean interaction energy or force between the particle and a heterogeneous surface, which differs significantly from a mean-field approach based on the average or nominal surface potential. Small variations in topography are found to remove large energy barriers to colloidal deposition. These results help explain the increased attraction of patchy surfaces towards particles relative to expectations based on typical DLVO calculations, which is particularly significant for surfaces with adsorbed polyelectrolytes.
A comparison of methionine, histidine and cysteine in copper(I)-binding peptides reveals differences relevant to copper uptake by organisms in diverse environments.

The N-terminal, extracellular regions of eukaryotic high affinity copper transport (Ctr) proteins vary in composition of the Cu(I) binding amino acids: methionine, histidine, and cysteine. To examine why certain amino acids are exploited over others in Ctrs from different organisms, the relative Cu(I) binding affinity and the dependence of binding on pH were examined for 3 peptides of the sequence MG2XG2MK, where X is either Met, His, or Cys. Cu(I) affinity was examined using an ascorbic acid oxidation assay, an electrospray ionization mass spectrometry technique, and spectrophotometric titration with a competitive Cu(I) chelator. The relative affinities of the peptides with Cu(I) reveal a trend whereby Cys > His > Met at pH 7.4 and Cys > Met > His at pH 4.5. Ligand geometry and metric parameters were determined with X-ray absorption spectroscopy. Susceptibility of the peptides to oxidation by hydrogen peroxide and copper-catalyzed oxidative conditions was evaluated by mass spectrometry. These results support hypotheses as to why certain Cu(I) binding amino acids are preferred over others in proteins expressed at different pH and exposed to oxidative environments. The results also have implications for interpreting site-directed mutagenesis studies aimed at identifying copper binding amino acids in copper trafficking proteins.
Management of Hodgkin's disease in a patient with sickle cell anemia

A right periauricular swelling developed in a 21-year-old woman with sickle cell anemia. The mass was removed and revealed Hodgkin's disease of the lymphocyte predominance type. While preparing the patient for a staging laparotomy, an allo-anti-Kell and an allo-antic-C were identified in the patient's sera. The patient's direct antiglobulin test was positive and an auto-anti-e was eluted from the patient's erythrocytes. The patient was treated with nine courses of MOPP therapy given over a nine-month period. The clinical and therapeutic implications for the management of patients with sickle cell anemia and lymphoproliferative disorders are discussed.
Tandem adaptation with a common design in Escherichia coli chemotaxis

We analyze a model for motor-level adaptation in Escherichia coli based upon the premise that clockwise (CW) and counter-clockwise (CCW) states have different preferred numbers of FliM subunits. We show that this model provides a simple mechanism for the recently observed motor-level adaptation, and it also explains the long-lasting puzzle on the thresholds observed when tethered cells are used to monitor responses to temporal ramps. We note that the motor-level adaptation has the same negative-feedback network design as the upstream receptor-level adaptation, and the tandem architecture of one control circuit followed by the other mitigates the effects of cell-to-cell variation and broadens the range of stimuli over which cells optimally respond.
Adaptive informal institutions and endogenous institutional change in China

Under certain circumstances, the etiology of endogenous institutional change lies in the informal coping strategies devised by local actors to evade the restrictions of formal institutions. With repetition and diffusion, these informal coping strategies may take on an institutional reality of their own. The author calls the resulting norms and practices adaptive informal institutions because they represent creative responses to formal institutional environments that actors find too constraining. Adaptive informal institutions may then motivate elites to reform the original formal institutions. This contention is illustrated by three major institutional changes that have occurred in the course of China's private sector development since the late 1970s—the legalization of private enterprise, the admission of capitalists into the Chinese Communist Party, and the amendment of the state constitution to promote the private economy.
Categorization of eosinophilic chronic rhinosinusitis.

PURPOSE OF REVIEW: The presence of eosinophilia histopathologically in sinusitis is frequently associated with greater disease objectively and a decreased likelihood of surgical success. Eosinophilic chronic rhinosinusitis encompasses a wide variety of etiologies and associations that can be grouped under this umbrella term. In addition, this term can be further divided into those patients with no polyps and those with polyps. The purpose of this review is to detail the epidemiology of eosinophilic chronic rhinosinusitis, to define known and potential subcategories, and to discuss targeted therapeutic interventions. Eosinophilia is frequently, but not exclusively, caused by IgE-mediated hypersensitivity and is dominated by the associated cytokine milieu of Th2 inflammation. Thus, allergic rhinitis or allergy is a subcategory and not synonymous with eosinophilic chronic rhinosinusitis. RECENT FINDINGS: Recent findings supporting mechanisms that promote eosinophilic infiltration are discussed and include the following subcategories: super antigen-induced eosinophilic chronic rhinosinusitis, allergic fungal sinusitis, nonallergic fungal eosinophilic chronic rhinosinusitis, and aspirin-exacerbated eosinophilic chronic rhinosinusitis. Undoubtedly there are other mechanisms and categorizations of eosinophilic chronic rhinosinusitis as yet unknown. It is possible, and in fact probable, that some patients may have overlapping mechanisms for eosinophilia. Corticosteroid therapy is an important treatment across all eosinophilic disorders and a profoundly potent but nonspecific antiinflammatory agent. Within each subcategory a specific antibacterial, antifungal, or immune modulation may be indicated. SUMMARY: The subcategories of eosinophilic chronic rhinosinusitis are discussed in light of recent findings and treatment recommendations.
Characteristics of MBE-grown heterostructure HgCdTe/CdTe/Si materials and planar photovoltaic devices

Abstract The recent developments in HgCdTe/CdTe/Si heterostructure materials and planar medium-wave infrared (MWIR) photovoltaic devices for IR imaging applications are discussed. The quality of the CdTe layers grown on different substrate orientations are compared. The HgCdTe grown on CdTe/Si is shown to be comparable with that of HgCdTe/CdZnTe. The I–V characteristics indicate the state-of-the-art performance of devices made on HgCdTe/Si.
Modification of Blood Vessel Diameter Following Perivascular Application of Botulinum Toxin-A

The purpose of this study was to demonstrate that perivascularly applied botulinum toxin-A (BTX) increases the diameter of treated blood vessels in a rat femoral vessel exposure model. Six adult Sprague–Dawley rats were used and bilateral femoral artery and vein exposures were performed. Five units of BTX were applied to the experimental side and an equal volume of sterile saline was applied to the control side. Digital images of the vessels were obtained at the following time points: pretreatment, immediately posttreatment, and postoperative days (POD) 1, 14, and 28. Vessel diameters were equivalent at baseline and immediately following application of BTX and saline. The BTX artery was significantly larger than the control artery on POD 1 and 14. The BTX treated artery was significantly larger than all other vessels on POD 14 (p < 0.05) as well as all prior time points (p < 0.01). Direct perivascular application of BTX increases the diameter of rat femoral vessels as early as POD 1. The affect is most robust on POD 14 where the artery was significantly larger than all other vessels at all time points. It is likely that the increased diameter of blood vessels results in an increased blood flow across the area of dilation. Such an increase in flow may serve to improve end-organ perfusion in microvascular procedures.
Achieving an AIDS-free world: science and implementation

When AIDS was first recognized in 1981, health professionals were ill equipped to address the emerging pandemic. Opportunistic infections were treated, and supportive care was provided in accordance with the regional availability of healthcare; however, even after HIV was recognized as the causative agent of AIDS, truly effective therapy would not be available for more than a decade. Prevention methods were similarly insufficient, as messages about safe sex and condoms often proved weaker than human impulse.
Two dynamic programming algorithms for which interpreted pebbling helps

We consider extensions of one-person and two-person pebble games that take into account the types of the gates of the circuits on which the games are played. A simple relationship is established between the extended games and the corresponding original games. This is useful in showing that the extended games allow more efficient pebbling than the original games on certain natural circuits for problems such as context-free language recognition and transitive closure of directed graphs.
Do we need biologic agents in preoperative systemic therapy of liver metastases

Liver metastases from colorectal cancer are common in patients who present with an initial diagnosis of metastatic disease or in those with recurrence. Without treatment, patients with metastatic disease have a poor prognosis. However, with surgical resection of the metastases, many patients may have the opportunity for long-term survival. The use of chemotherapy in patients undergoing surgery has augmented the long-term survival benefits that are gained with surgery. The use of preoperative chemotherapy may convert a portion of initially unresectable liver metastases to resectable ones. A growing body of literature is helping to define the role of chemotherapy in this setting. The introduction of newer biologic agents (eg, cetuximab and bevacizumab) has led to meaningful improvements in response rates and survival for metastatic colorectal cancer patients. However, further trials are required to better determine the benefits of chemotherapy and biologic agents in the management of patients with liver metastases.
Human immunodeficiency virus and hepatitis B virus seroprevalence in an urban trauma population.

Objective : To determine the seroprevalence of the human immunodeficiency virus (HIV) and the hepatitis B virus (HBV) in patients of an urban level I trauma center. Design : Prospective, blinded point prevalence study of serum HIV and HBV antibody and antigen. Setting : An urban level I trauma center that participates in a trauma system serving three million people. Patients : The study included 994 (94.8%) of 1049 consecutive trauma service patients treated between June 6, 1988 and September 22, 1988. The patients were 82.2% male and 73.1% black, with a mean age of 28.8 ± 12.3 years. Blunt trauma was seen in 65.4% of patients, 5.2% were in shock, and 96.2% survived their trauma. Main Outcome Measures : HIV and HBV seroprevalence, using both antibody and antigen testing. Results : HIV infection was seen in 43 patients (4.3%) ; 41 (95.3%) were HIV Ab+ and two (4.7%) were HIV Ab-/HIV Ag+. Infection with the HBsAg was seen in 31 patients (3.1%). Infection with either virus was seen in 70 patients (7%) ; four patients (0.4%) were infectious for both viruses. Infection was related to age 20 to 49 years, IV drug use, a hepatitis or sexually transmitted disease history, prior HIV testing, shock, and death (p < 0.05). Penetrating trauma was not predictive of infection. In a logistic regression model, IV drug use was the single significant predictor of infection (p < 0.05). Conclusions : Young urban trauma patients, because of drug-related intentional violence, are 15.3 to 17.6 times more likely to be HIV infected and 3.9 to 7.9 times more likely to be infectious for HIV or HBV than the trauma population overall. The 12 to 21% infection rates in critically injured patients who require shock resuscitation and/or die reinforces the need for mandated universal precautions and for clear policies which govern the performance of procedures by physicians in training. Primary HIV infection in critically injured patients may worsen their outcome and may adversely affect the exposed health care worker. Emergency departments and trauma units should develop a referral system to HIV primary care services (HIV counselling and testing) for high risk patients and for adversely exposed health care workers.
The role of mantle CO2 in volcanism

Abstract Carbon dioxide is the propellant gas in volcanic eruptions and is also found in mantle xenoliths. It is speculated that CO 2 occurs as a free gas phase in the mantle because there is no reason to expect CO 2 to be so universally associated with volcanic rocks unless the CO 2 comes from the same source as the volcanic rocks and their xenoliths. If correct, the presence of a free gas in the mantle would lead to physical instability, with excess gas pressure providing the cause of both buoyancy of volcanic melts and seismicity in volcanic regions. Convection in the mantle and episodic volcanic eruptions are likely necessary consequences. This suggestion has considerable implications for those responsible for providing warnings of impending disasters resulting from volcanic eruptions and earthquakes in volcanic regions.
Structural requirements for pep binding To EPSP synthase

Abstract Evaluation of structural analogs of PEP as inhibitors ESPS synthase demonstrate that this enzyme displays a high degree of structural and ionic specificity for PEP binding. Both carboxyallenyl phosphate (1) and (Z)-3-fluoro-PEP (5) were surprisingly potent EPSP sythase inhibitors.
Infinite Utility and Temporal Neutrality

Suppose that time is infinitely long towards the future, and that each feasible action produces a finite amount of utility at each time. Then, under appropriate conditions, each action produces an infinite amount of utility. Does this mean that utilitarianism lacks the resources to discriminate among such actions? Since each action produces the same infinite amount of utility, it seems that utilitarianism must judge all actions permissible, judge all actions impermissible, or remain completely silent. If the future is infinite, that is, the prospects for utilitarianism look bleak.
Recent Developments in Health Care Law: Partners in Innovation

This article reviews recent developments in health care law, focusing on the engagement of law as a partner in health care innovation. The article addresses: the history and contents of recent United States federal law restricting the use of genetic information by insurers and employers; the recent federal policy recommending routine HIV testing; the recent revision of federal policy regarding the funding of human embryonic stem cell research; the history, current status, and need for future attention to advance directives; the recent emergence of medical–legal partnerships and their benefits for patients; the obesity epidemic and its implications for the child’s right to health under international conventions.
Karyology of pseudogamous Ips bark beetles

Females in unisexual strains of North American Ips tridens, I. borealis, I. pilifrons, and I. perturbatus and I. acuminatus from Norway and Bulgaria are triploid (3n=48) and are associated with males and diploid (2n=32) females that produce bisexual broods. Triploid females require insemination for brood production, but male-contributed genes do not appear in their offspring: inheritance of morphological markers (frons shape and setation) in North American spp. is strictly mother-to-daughter, as has been shown for isozymes in I. acuminatus. These unisexual Ips strains are therefore pseudogamous (=gynogenetic). For the North American spp., morphological markers and the prevalence of all-female strains in natural populations indicate that pseudogamy has arisen sporadically. Triploid lines may arise by fertilization of diploid ova by normal sperm. The occurrence of diploid ova was inferred from observations of putatively diploid and tetraploid spermatozoa associated with distortions in meiosis of hybrid males and of nonhybrid males affected by apparently genetically-controlled asynapsis at first meiosis.
Photoelectron spectroscopy and thermochemistry of tert-butylisocyanide-substituted cobalt tricarbonyl nitrosyl.

A new organometallic complex, Co(CO)2NOtBuNC, was synthesized and investigated by photoelectron spectroscopy (PES) and threshold photoelectron photoion coincidence (TPEPICO) spectrometry in order to determine its ionization energy as well as the bond energies in the ionic forms. The assignment of the nine peaks in the PES was based on Kohn−Sham molecular orbital energies, and an adiabatic ionization energy of 7.30 ± 0.05 eV was determined. In the TPEPICO experiment, the following 0 K onsets were determined for the various fragment ions: CoCONOtBuNC+ (8.17 ± 0.05 eV); CoNOtBuNC+ (9.01 ± 0.05 eV); and CotBuNC+ (10.42 ± 0.05 eV). Because the photon source did not extend above 14 eV, we could not observe the bare Co+ ion in the experiment. The heat of formation of the CotBuNC+ ion was estimated by ab initio and DFT calculations of the CoL+ + tBuNC → CotBuNC+ + L (L = CO, NO, NH3, H2O, PMe3) substitution enthalpies.
Multiresolution anomaly detection method for fractional Gaussian noise

Driven by network intrusion detection, we propose a MultiResolution Anomaly Detection (MRAD) method, which effectively utilizes the multiscale properties of Internet features and network anomalies. In this paper, several theoretical properties of the MRAD method are explored. A major new result is the mathematical formulation of the notion that a two-scaled MRAD method has larger power than the average power of the detection method based on the given two scales. Test threshold is also developed. Comparisons between MRAD method and other classical outlier detectors in time series are reported as well.
An Evaluation of the I.R.E. Professional Group Plan

The rapid growth during the past ten years of the radio engineering profession resulted in the initiation by the I. R. E. of the Professional Group Plan. The significant steps in the development of the Professional Groups are reviewed and the value of the Professional Group Plan to the Institute and to the Profession as a whole is evaluated. The importance of realistic consideration of problems arising from the group expansion program is stressed.
Multirater congruence on the social skills rating system: mother, father, and teacher assessments of urban head start children’s social competencies

Abstract This study examined the relationships between parent and teacher and between mother and father SSRS reports of 134 urban Head Start children to assess the cross-informant capacity of the SSRS. The findings documented an insignificant relationship between parent and teacher SSRS ratings of children’s social competence. The results revealed significant congruence between SSRS ratings of mothers and fathers. Mothers and fathers who reported higher levels of sharing childcare responsibilities evidenced higher levels of agreement on SSRS ratings of children. This study discusses the importance of Head Start staff, parent, and research partnerships for developing scales that have the capacity to foster home-school communications about children.
The Spine in Osteogenesis Imperfecta

The spine is a frequent site of deformity in osteogenesis imperfecta (OI). Poor bone stock, hypotonia, and repeated compression fractures contribute to the development of deformity. The more severe types of OI are more likely to develop spinal deformity. Scoliosis in OI is commonly associated with a kyphotic component. When a deformity appears to be progressive, early intervention is indicated. Some patients with OI may be candidates for bracing, but some form of operative treatment is ultimately needed for curve control. Standard fusion and instrumentation techniques or nonfusion procedures may be used. Careful handling of the patients and their spines is important to avoid complications.
Toxicity of Mitomycin C Toward Cultured Pulmonary Artery Endothelium

Mitomycin C (MMC) is a bifunctional alkylating agent used in cancer chemotherapy. MMC therapy occasionally results in pulmonary vascular injury, including alterations in endothelial cells. Reactive metabolites of MMC can cross-link DNA, and its cytotoxicity has been attributed in part to this capacity, but effects in vascular cells have not been explored extensively. Accordingly, the direct effects of MMC on cultured porcine pulmonary artery endothelial cells (PECs) were examined. A single administration of MMC (0-10 microM) to PEC monolayers resulted in concentration-dependent cytolytic injury that was delayed in onset and progressive in nature. Cells treated at subconfluent densities were inhibited in their ability to proliferate. MMC treatment resulted in DNA cross-linking at concentrations (0.01-1 microM) that inhibited cell proliferation but caused only limited overt cytotoxicity, supporting an association between DNA cross-linking and impairment of cell division. This pattern of PEC injury is reminiscent of that seen after treatment with another pneumotoxic, bifunctional alkylating agent, monocrotaline pyrrole. The similarity of the endothelial cell response to different bifunctional alkylating agents suggests that DNA cross-linking may inhibit cell proliferation and thereby limit the repair capacity of endothelial monolayers. This might contribute to the progressive pulmonary vascular injury that occurs after administration of certain DNA cross-linking agents in vivo.
Ultrafast electron diffraction. Velocity mismatch and temporal resolution in crossed-beam experiments

The time resolution of crossed-beam experiments is explicitly related to velocity mismatch and other beam parameters. Application of this general treatment to ultrafast electron diffraction reveals that a time resolution of approximately 1.4 picoseconds can be achieved under conventional conditions. It is possible to reduce this value by increasing the electron energy, varying the angle between the electron and laser pulses, and reducing the focal width of the laser and the size of the molecular beam.
Geometric phases in the motion of rigid bodies

In this paper we make some differential-geometric observations on the kinematics of convex surfaces rolling along a fixed plane in ℝ3, and on the relationship of the problem with parallel transport and the Gauss-Bonnet formula. These ideas are then applied to recover “Berry's phase” of a free rigid body which was found by Montgomery using Stokes' Theorem. We also point out a new “twist” on this problem. As a second application, we give a solution of a problem posed by R. Brockett. As a third application, we give a geometrical description of “Berry's phase” in SO(3); this can be applied to various rigid-elastic systems to compute their geometric phases.
Zipeprol: preclinical assessment of abuse potential

Abstract Zipeprol was evaluated in a number of in vitro and in vivo assays predictive of stimulant, depressant, or opioid abuse potential. Zipeprol had affinity for β and κ opioid binding sites as well as δ binding sites. However, it failed to exert opioid-like agonist actions in rodents, and did not attenuate withdrawal signs in morphine- or pentobarbital-dependent rats. Zipeprol did not substitute for either amphetamine or pentobarbital in drug discrimination assays in rhesus monkeys. On the other hand, it suppressed morphine withdrawal signs in rhesus monkeys in two assays, and it acted as a quadazocine-sensitive reinforcer in monkeys trained to self-inject alfentanil. Zipeprol also acted as a reinforcer in monkeys trained to self-inject methohexital. In a dose range of 10–18 mg/kg, zipeprol induced convulsions in monkeys. Zipeprol appears to have abuse potential and a novel spectrum of action involving both opioid and non-opioid effects.
Altered Sensitivity to Single-strand-specific Reagents Associated with the Genomic Vascular Smooth Muscle α-Actin Promoter during Myofibroblast Differentiation

Stimulation of quiescent AKR-2B mouse fibroblasts with transforming growth factor β1 results in uniform conversion to a myofibroblast-like phenotype as judged by a rapid accumulation of smooth muscle α-actin mRNA and protein. Because transcriptional regulation of the smooth muscle α-actin gene in these cells might be mediated by single-stranded DNA-binding proteins, we have examined the sensitivity of genomic DNA to chemical reagents with specificity for unpaired bases in a region of the promoter previously implicated in Purα, Purβ, and MSY1 binding in vitro (Kelm, R. J., Jr., Cogan, J. G., Elder, P. K., Strauch, A. R., and Getz, M. J. (1999) J. Biol. Chem. 274, 14238–14245). Our data reveal specific differences between purified DNA treated in vitro and nucleoprotein complexes treated in living cells. Although some differences were observed in quiescent cells, treatment with transforming growth factor β1 resulted in the development of additional sensitivity within 1 h. This enhancement was most pronounced in bases immediately upstream of an MCAT enhancer element-containing polypurine-polypyrimidine tract. A TATA-proximal element of similar base distribution showed no such hyperreactivities. These results suggest that activation of the endogenous smooth muscle α-actin gene during myofibroblast conversion is accompanied by specific structural changes in the promoter that are consistent with a decline in single-stranded DNA repressor protein binding.
Magnetic neutral sheets in evolving fields. I - General theory. II - Formation of the solar corona

The problem of the hydrostatic equilibrium of a large-scale magnetic field embedded in a fluid with infinite electrical conductivity is considered. It is pointed out that a necessary condition for static equilibrium is the invariance of the small-scale pattern in the field along the large-scale direction. A varying topological pattern implies that no fluid pressure distribution exists for which the field is everywhere static. Magnetic neutral sheets form, and dynamical reconnection of the field takes place. It is shown here that the invariance is also a sufficient condition for the existence of a fluid pressure distribution producing static equilibrium. Even in the simplest cases, however, the requirements on the fluid pressure are extreme and, a priori, are unlikely. It is concluded that almost all twisted flux tubes packed together produce dynamical nonequilibrium and dissipation of their twisting. This is the basic effect underlying the long-standing conjecture that the shuffling of the footpoints of the bipolar magnetic fields in the sun is responsible for heating the active corona. Attention is then given to the consequences of this general dynamical dissipation in the magnetic fields that produce the active corona of the sun. The footpoints of the field are continually manipulated by the subphotospheric convection in such a way that the lines of force are continually wrapped and rotated about one another.
Photofragmentation-laser induced fluorescence: a new method for detecting atmospheric trace gases

A new method for the in situ detection of nonfluorescing molecular species is proposed: photofragmentation-laser induced fluorescence (PF-LIF). In this approach, the species to be detected is first laser photolyzed at a wavelength lambda (1), producing one or more vibrationally excited photofragments. Before vibrational relaxation occurs, one of these photofragments is pumped into a bonding excited state by a second laser pulse centered at wavelength lambda (2). Fluorescence is sampled at a wavelength lambda (3), where lambda (3) is less then lambda (2) and lambda (1). This pumping configuration thus permits massive discrimination against Rayleigh and Raman scattering as well as white noise fluorescence from the laser wavelengths lambda (1) and lambda (2). The technique should be both highly sensitive and selective for numerous atmospheric trace gases. Specific sampling schemes for detecting NO2, NO3, and HNO2 are proposed. Various noise sources and chemical interferences are discussed. Specific calculations that estimate the sensitivity of the PF-LIF system for detecting NO2, NO3, and HNO2 are given.
Examining the relationship between the microstructure of calcium silicate hydrate and drying shrinkage of cement pastes

Abstract Cement paste undergoes a volumetric contraction called drying shrinkage when placed in a low relative humidity (RH) environment. Only a portion of this shrinkage is reversible upon rewetting. In order to understand better the mechanisms responsible for the irreversible portion of drying shrinkage, a quantitative comparison was made between shrinkage values and microstructural properties of cement pastes. Drying shrinkage, surface area and pore volume were manipulated using curing temperature and chemical admixtures. It was observed that total and irreversible drying shrinkage increase with surface area and pore volume as measured by nitrogen (1–40 nm pore radius range), when degree of hydration and water-to-cement ratio (w/c) are held constant (0.55 and 0.45, respectively).
New P-MOSFET Hot-Carrier Degradation Model for Bi-Directional Operation

It has been recognized that the building in reliability for hot-carrier is important in submicrometer p-MOSFET's as well as n-MOSFET's for use in the design of ULSI's. Therefore in this paper, we introduce a new hot-carrier degradation model of p-MOSFET's for bi-directional operation, aiming at constructing a new reliability simulator to cope with various operation modes. This model is based on the trap-induced barrier lowering (TIBL), the channel length modulation (CLM) due to electron traps in the oxide, and the mobility modulation (MM) due to interface state generation. By extracting these physically related parameters from transistor characteristics after hot-carrier injection in addition to extracting transistor model parameters before the injection, the hot-carrier degradation can be predicted not only in the linear and saturation regions but also in the forward and reverse operation modes.
Late Quaternary Floodplain History of the Brazos River in East-Central Texas

The floodplain along a 75-km segment of the Brazos River, traversing the Gulf Coastal Plain of Texas, has a complex late Quaternary history. From 18,000 to 8500 yr B.P., the Brazos River was a competent meandering stream that migrated from one side of the floodplain to the other, creating a thick layer of coarse-grained lateral accretion deposits. After 8500 yr B.P., the hydrologic regime of the Brazos River changed. The river became an underfit meandering stream that repeatedly became confined within narrow and unstable meander belts that would occasionally avulse. Avulsion occurred four times; first at 8100 yr B.P., then at 2500 yr B.P., again around 500 yr B.P., and finally around 300 yr B.P. The depositional regime on the floodplain also changed after 8500 yr B.P., with floodplain construction dominated by vertical accretion. Most vertical accretion occurred from 8100 to 4200 yr B.P. and from 2500 to 1250 yr B.P. Two major and three minor periods of soil formation are documented in the floodplain sequence. The two most developed soils formed from 4200 to 2500 yr B.P. and from around 1250 to 500 yr B.P. These changes on the floodplain appear to be the result not of a single factor, but of the complex interplay among changes in climate, sediment yield, and intrinsic floodplain variables over time.
Laser-excited time-resolved Shpol'skii spectroscopy for the direct analysis of dibenzopyrene isomers in liquid chromatography fractions.

We present a unique method for the unambiguous determination of dibenzo[a,l]pyrene, dibenzo[a,e]pyrene, dibenzo[a,h]pyrene, dibenzo[a,i]pyrene, and dibenzo[e,l]pyrene in high-performance liquid chromatography (HPLC) fractions. Chemical analysis is performed via laser-excited time-resolved Shpol'skii spectroscopy with the aid of a cryogenic fiber-optic probe, pulsed tunable dye laser, spectrograph, and intensified charge-coupled device. Unambiguous identification is accomplished via wavelength time matrix formats, which give simultaneous access to spectral and lifetime information. Prior to spectroscopic analysis, HPLC fractions are pre-treated with liquid–liquid extraction or solid–liquid extraction at the tip of the fiber-optic probe. Solid–liquid extraction gives the best limits of detection, which vary from 40 pg mL-1 (dibenzo[a,l]pyrene) to 0.2 ng mL-1(dibenzo[e,l]pyrene).
Clinical application of sonoelastography in thyroid, prostate, kidney, pancreas, and deep venous thrombosis

This article reviews the clinical applications of current ultrasound elastography methods in non-hepatic conditions including thyroid nodules, prostate cancer, chronic kidney disease, solid renal lesions, pancreatic lesions, and deep vein thrombosis. Pathophysiology alters tissue mechanical properties via ultrastructural changes including fibrosis, increased cellularity, bleeding, and necrosis, creating a target biomarker, which can be imaged qualitatively or quantitatively with US elastography. US elastography methods can add information to conventional US methods and improve the diagnostic performance of conventional US in a range of disease processes.
Functional analysis of the 5' flanking sequence in the ovine beta 1-adrenergic receptor gene.

Abstract Functional data for the promoter of the β 1 -adrenergic receptor (β 1 AR) gene are lacking. We previously cloned the ovine β 1 AR gene and mapped the transcription start sites. We now report data on ovine β 1 AR gene expression obtained by transient transfection. Progressive deletion of upstream 5′ flanking region moderately increased transcription activity in three cell lines compared to the full-length promoter. Deletion of sequences between −1530 and −953 produced the greatest increase in transcriptional activity. This region encompassed a putative GRE and an AP1 site. Deletion of the transcription start sites eliminated nearly all of the activity. Dexamethasone significantly increased activity of each of the promoter constructs tested in C6 glioma cells and an embryonic myocardial cell line, W1 cells. T3 alone had no effect and cotreatment with T3 did not augment the effects of dexamethasone. We conclude, basal transcription activity is repressed by a mechanism which operates through element(s) in the proximal promoter. Glucocorticoids increase transcription through mechanism(s) within the same region. We speculate that this region in the ovine β 1 AR promoter may be responsible for its unique transcription regulation.
Sparse quadratic programming in chemical process optimization

The quadratic programming aspects of a full space successive quadratic programming (SQP) method are described. In particular, fill-in, matrix factor and active set updating, numerical stability, and indefiniteness of the Hessian matrix are discussed in conjunction with a sparse modification of Bunch and Parlett factorization of symmetric indefinite (Kuhn-Tucker) matrices of the type often encountered in optimization. A new pivoting strategy, called constrained pivoting, is proposed to reduce fill-in and compared with complete, partial and threshold pivoting. It is shown that constrained pivoting often significantly reduces fill-in and thus the iterative computational burdens associated with the factorization and solution of Kuhn-Tucker conditions within the QP subproblem. A numerical algorithm for updating the lower triangular and diagonal factors is presented and shown to be very fast, usually requiring only about 5% of the cost of refactorization. Two active set strategies are also presented. These include the options of adding inequalities either one or several at a time. In either case, the effects on matrix factor updating is shown to be small. Finally, a simple test is used to maintain iterative descent directions in the quadratic program. Our sparse symmetric indefinite QP algorithm is tested in the context of a family of SQP algorithms that include a full space Newton method with analytical derivatives, a full space BFGS method and a Range and Null space Decomposition (RND) method in which the projected Hessian is calculated from either analytical second derivatives or the BFGS update. Several chemical process optimization problems, with small and large degrees of freedom, are used as test problems. These include minimum work calculations for multistage isothermal compression, minimum area targeting for heat exchanger networks, and distillation optimizations involving some azeotropic and extractive distillations. Numerical results show uniformly that both the proposed QP and SQP algorithms, particularly the full space Newton method, are reliable and efficient. No failures were experienced at either level.
Use of marijuana and other drugs among adult marijuana users: A longitudinal study

Abstract The drug use of 97 adult regular marijuana-user volunteers who were interviewed in 1970 and were re-interviewed in 1976 is presented. At the original interview the majority were using marijuana one to four times per week. By follow-up, most had either decreased to only occasional use or had increased to near daily use. Use of cigarettes, hallucinogens, stimulants, barbiturates, and opiates had declined. Alcohol was being more frequently used at follow-up. Use of nearly all substances reported at the original interview was correlated with the use reported at follow-up. Five global levels of drug use were examined, from those using very little alcohol and no cigarettes (level 1) to marijuana use (level 3) to use of substances from among four categories of “harder” drugs (level 5). The majority of persons had moved to a lower level by follow-up, with only 10% moving to a higher level. Marijuana-use frequency was related to extent of other drug use at the original but not at the follow-up interview. Cessation of harder drug use was found to be best predicted by marriage, and by having friends who were not marijuana users.
NRLEUV 2: A new model of solar EUV irradiance variability

Abstract NRLEUV represents an independent approach to modeling the Sun’s EUV irradiance and its variability. Instead of relying on existing irradiance observations, our model utilizes differential emission measure distributions derived from spatially and spectrally resolved solar observations, full-disk solar images, and a database of atomic physics parameters to calculate the solar EUV irradiance. Recent updates to the model include the calculation of a new quiet Sun differential emission measure distribution using data from the CDS and SUMER spectrometers on SOHO and the use of a more extensive database of atomic physics parameters. Here, we present comparisons between the NRLEUV quiet Sun reference spectrum and solar minimum irradiance observations. Although there are many areas of agreement between the modeled spectrum and the observations, there are some major disagreements. The computed spectra cannot reproduce the observed irradiances at wavelengths below about 160 A. The observed irradiances appear to overstate the magnitude of the EUV continua. We also present some initial comparisons between the NRLEUV irradiance variability model and TIMED/SEE data. We find that the NRLEUV model tends to overpredict the absolute magnitude of the irradiance at many wavelengths. The model also appears to underpredict the magnitude of the solar-cycle and solar rotational variation in transition region emission lines.
The characterization and regulation of a polyamine-responsive, cyclic nucleotide-independent protein kinase activity in the mouse mammary gland.

The existence of two cyclic nucleotide-independent protein kinases in the cytosolic extract of mouse mammary gland has been determined via DEAE-cellulose and Sephacryl column chromatography. Both enzymes phosphorylated casein in the absence of the exogenous cyclic nucleotides, cAMP and cGMP. One protein kinase was found to have a molecular weight of approx. 30 000, while the other was found to have a molecular weight in the range 150 000–250 000. The activity of the larger species was enhanced by polyamines and inhibited by heparin. This enzyme utilized both ATP and GTP as phosphate donors; the apparent Km values were 10 and 16 μM, respectively. The lower molecular weight protein kinase was not affected by either polyamines or heparin and utilized only ATP (Km = 8 μM) as the phosphate donor. The polyamine-responsive protein kinase activity in the mammary gland varied as a function of the reproductive development of the mouse. The activity was relatively low in the virgin and primiparous stages, increased during pregnancy and peaked during lactation. Studies using mammary organ culture indicated that the combination of insulin (5 μg/ml), cortisol (1 μg/ml) and prolactin (5 μg/ml) maintained the polyamine-responsive protein kinase activity that was present in noncultured tissue. In the absence of prolactin, however, the kinase activity was significantly lower than that observed in the three-hormone system. When dibutyryl cyclic AMP (0.5 mM) was added to the medium along with the three hormones, a significant decrease in enzyme activity was found. Slab gel electrophoresis and autoradiography showed that the majority of the phosphorylated endogenous substrates in the cytosolic fraction were caseins. The results of this study suggest that the polyamine-responsive protein kinase may play an important role in the growth and development of the mammary gland.
A computational method for subsonic compressible flow in diffusers

Integral methods are used to model subsonic flow in planar diffusers operating with or without stall. Turbulent boundary layers are computed with a lag-entrainment method employing new correlations for shape factor and skin friction, which are based on a Coles-Van Driest velocity profile. The inviscid flow is modeled as one dimensional and is easily coupled with the boundary layer method to yield equations that can be solved by integrating in the downstream direction. Analysis of the equations describing flow in a diffuser shows that the boundary layer separation singularity may not be eliminated by viscous-inviscid interaction; a modified interaction scheme is used to guarantee a non-singular equation set. The nature of this singularity offers an explanation for the apparent universality of asymmetric stall in planar diffusers. Results for several flows demonstrate the accuracy and range of applicability of the method.
Cognitive impact of genetic variation of the serotonin transporter in primates is associated with differences in brain morphology rather than serotonin neurotransmission

A powerful convergence of genetics, neuroimaging and epidemiological research has identified the biological pathways mediating individual differences in complex behavioral processes and the related risk for disease. Orthologous genetic variation in non-human primates (NHPs) represents a unique opportunity to characterize the detailed molecular and cellular mechanisms that bias behaviorally and clinically relevant brain function. We report that a rhesus macaque orthologue of a common polymorphism of the serotonin transporter gene (rh5-HTTLPR) has strikingly similar effects on behavior and brain morphology to those in humans. Specifically, the rh5-HTTLPR (S)hort allele broadly affects cognitive choice behavior and brain morphology without observably affecting the 5-hydroxytryptamine (5-HT) transporter or 5-HT1A concentrations in vivo. Collectively, our findings indicate that 5-HTTLPR-associated behavioral effects reflect genotype-dependent biases in cortical development rather than static differences in serotonergic signaling mechanisms. Moreover, these data highlight the vast potential of NHP models in advancing our understanding of human genetic variation affecting behavior and neuropsychiatric disease liability.
Simultaneous radio and X-ray observations of MXB1837 + 05 (Ser X−1)

DURING a continuing program of radio observations of X-ray sources carried out with the NRAO very large array (VLA), we have made high sensitivity searches for radio emission from MXB1837 + 05 = Ser X − 1 (ref. 1), particularly during the SAS 3 MIT world-wide X-ray burster watch in June 19772. Observations of MXB1837 + 05 were carried out on 26 April, 12 and 13 June 1977, with six 25-m antennas of the VLA operated at 4,884 MHz with system temperatures of ∼60 K and bandwidths of 50 MHz. Upper limits of 1 mJy were obtained for the time-averaged radio emission from Ser X − 1 during the three periods of observation, and no short time scale radio emission was detected during or after the times X-ray bursts were observed on 12 and 13 June 1977.
Environmental contaminant concentrations in biota from the lower Savannah River, Georgia and South Carolina.

Planned harbor expansion and industrial developments may adversely affect the economically important aquatic resources of the lower Savannah River, including those at the Savannah National Wildlife Refuge. To establish the present level of chemical contamination in this system, we collected a total of 102 samples of nine species of fish and fiddler crabs (Uca pugilator) from eleven sites in the lower Savannah River and on the Savannah National Wildlife Refuge, and analyzed them for concentrations of organochlorine chemicals, aliphatic and aromatic petroleum hydrocarbons, and 13 elemental contaminants: aluminum, arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, selenium, and zinc. Residues of DDT (mainly as DDE),trans-nonachlor, dieldrin, Aroclor® 1260, mirex, and petroleum hydrocarbons were common in fish from the lower Savannah River, but concentrations were below those warranting environmental concern. In general, the concentrations of elemental contaminants also were low; however, arsenic, cadmium, and chromium concentrations were elevated in fish from river stations near the city of Savannah, and lead was elevated in samples from the National Wildlife Refuge. Contamination of the lower Savannah River by organic and elemental contaminants, as indicated by concentrations in fishes and fiddler crabs, did not appear to pose a hazard.
Privatization and Price Convergence: Evidence from Four Markets in Kyiv☆

Abstract The evolution of prices of three commodities at four market locations in Kyiv, Ukraine, is examined. The interconnected effects of increased market orientation and of privatization are separated and evaluated through use of an error-correction statistical methodology. The data cover the period from April 12, 1993 to December 31, 1996. There is significant evidence of price convergence due to arbitrage by buyers and sellers at these markets. There are also a secular trend toward greater market integration over time and a once-off reduction in price differentials associated with the privatization of formerly state shops. J. Comp. Econom., June 1999, 27(2), pp. 231–257. Department of Economics, Gardner Hall, CB 3305, University of North Carolina, Chapel Hill, North Carolina 27599-3305.