cssi/SciSciGPT-SciSciNet huggingface dataset:
Polymer-coated cannulas for the reduction of backflow during intraparenchymal infusions.

Infusate backflow or leak-back along the cannula track can occur during intraparenchymal infusions resulting in non-specific targeting of therapeutic agents. The occurrence of backflow depends on several variables including cannula radius, infusate flow rate, and tip location. In this study, polymer coatings that swell in situ were developed and tested with in vitro hydrogel experiments for backflow reduction. Coatings were applied to the external cannula surface in a dual layer arrangement with a poly(vinyl alcohol) outer layer atop an inner poly(ethylene oxide) and alginate layer. Once these coated cannulas were inserted and allotted an 8–10 min waiting period for hydration, backflow during infusions of 4.0 μl of a macromolecular tracer (Evans Blue labeled albumin) was reduced significantly under flow rates of 0.3–0.6 μl/min, allowing for more effective distribution within targeted regions. Polymer coating thicknesses before and after hydrations were 0.035 and 0.370 mm, respectively. Also, backflow data was fit to a model to estimate the effective local compressive stress caused by the hydrated polymers. After withdrawal of the cannula from the insertion site, the hydrated polymer coatings remained within the cavity left in the hydrogel tissue phantom and formed a seal at the infusion site that prevented further backflow during needle withdrawal. Ex vivo infusions in excised porcine brain tissues also showed significant backflow reduction while also demonstrating the ability to leave a polymer seal in the tissue cavity after cannula removal. Thus, application of these polymers as needle or cannula coatings offers a potentially simple method to improve targeting for local drug delivery.
Addressing Issues of Social Justice through Reflective Writing

Since the1960’s there have been calls for reforms in teacher education programs to reflect the growing diversity represented in our nation’s schools. One response is multicultural education courses aimed at addressing attitudes and beliefs about diversity. Such courses have received mixed reviews. Some research has reported that pre-service teacher’s attitudes and beliefs were changed in a positive direction towards diversity, while others suggest that pre-service teachers leave these courses unchanged. The primary goal of this study was to determine if a stand-alone multicultural education course challenged or altered pre-service teachers’ attitudes and beliefs towards cultural diversity. An analysis of reflective writings by the participants throughout the semester served as evidence of change.
Prostate cancer: Prostate Health Index--improving screening in men with family history.

Although the optimal protocol of screening men for prostate cancer remains undefined, the Prostate Health Index—phi—might provide an additional tool to improve risk stratification, especially for men with a positive family history.
The frequency and distribution of idiopathic osteosclerosis

Full-mouth radiographs of 1921 patients were examined for the presence of radiopacities that could not be attributed to any known sources of bone formation. A total of 103 patients, or 5.4%, exhibited these foci of idiopathic osteosclerosis. Most lesions were located in the vicinity of the mandibular premolars, and the majority had some connection to the apices of the teeth. No difference in frequency between males and females was detected overall, but a statistically significant preponderance of idiopathic osteosclerosis was found in blacks, with a predilection for black females also noted.
BILATERAL NERVE GRAFT DURING RADICAL RETROPUBIC PROSTATECTOMY: 1-YEAR FOLLOWUP

Purpose: With the interposition of a sural nerve graft to replace resected cavernous nerves at radical retropubic prostatectomy, we have previously reported the return of effective erectile function. We determine the efficacy of this procedure in a series of men with at least 1-year followup.Materials and Methods: A total of 12 potent men (mean age plus or minus standard deviation 57 ± 6 years) with clinically localized prostate cancer underwent radical retropubic prostatectomy, with deliberate wide bilateral neurovascular bundle resection and placement of bilateral nerve grafts. A series of patient and partner erectile dysfunction questionnaires, and patient interviews were performed at 3, 6, 12 and 18 months postoperatively. Only results for those men with a followup of 12 months or greater (mean 16 ± 4) are presented. A control group of 12 men who had undergone bilateral nerve resection but declined nerve graft placement, was also followed.Results: Of the 12 men 4 (33%) had spontaneous medically unassi...
Calcium-Activated, Phospholipid-Dependent Protein Kinase in Pig Epidermis

We investigated calcium-activated, phospholipid-dependent protein kinase in pig epidermis. Pig epidermal homogenates were centrifuged at 30,000 g for 30 min, and the supernatant was applied on a DEAE-cellulose column for purification. The partially purified enzyme was stimulated by simultaneous addition of Ca2+ and phospholipid. Successive addition of small amounts of diolein further activated the enzyme activity. The calcium-activated phospholipid-dependent protein kinase preferentially phosphorylated serine residues and its endogenous substrate protein in the pig epidermis has a molecular weight of about 97,000.
Improving recruitment, retention, and adherence to 6-month cycling in Alzheimer's disease

There is a pressing need to establish recruitment, retention, and adherence feasibility to inform clinical trials that will evaluate how exercise affects the symptoms and disease trajectory in Alzheimer's disease (AD). This paper reported the recruitment rate, retention, and adherence from a 6-month cycling study in community-dwelling older adults with mild-to-moderate AD using a single-group, repeated-measures design. Seven recruitment strategies were tested. Participants were prescribed an individualized, 15-45-min moderate intensity cycling 3 times a week for 6 months. The results showed a 1.87 recruitment rate (No. of participants recruited per month per site), 78.6% retention (No. of completers/No. of enrolled participants), and 86.4% adherence (number sessions meeting prescription dose/total number of sessions). The findings addressed a major gap in aerobic exercise studies in AD. Successful recruitment relies on community partnership, whereas strategies for ensuring participant exercise safety collectively improved retention and adherence.
The formation and acetylation of π-cyclopentadienyl-gp-cyclobutadienerhodium

Abstract The photolysis of π-cyclopentadienyldicarbonylrhodium and photo-α-pyrone in benzene solution has produced the first unsubstituted π-cyclobutadiene derivative of rhodium, π-cyclopentadienyl-π-cyclobutadienerhodium. The product has been characterized by elemental, IR, NMR and mass spectral analyses. π-Cyclopentadienyl-π-cyclobutadienerhodium undergoes Friedel-Crafts acetylation with acetic anhydride and stannic chloride on the π-cyclobutadiene ring to form π-cyclopentadienyl-π-acetylcyclobutadienerhodium in 25% yield.
A pseudoaneurysm of the superficial femoral artery as a late complication of a stab wound

Limited arteriography based on clinical indications has become increasingly popular. We present the case of a patient with pseudoaneurysm formation of the superficial femoral artery as a late consequence of a lateral stab wound to the thigh. This case demonstrates the need for postinjury follow-up to identify missed injuries before they are limb threatening.
High-n ballooning modes in highly elongated tokamaks

An analytic study of stability against high-n ballooning modes in highly elongated axi-symmetric plasmas is presented and compared with computational results. – From the equation for the marginal pressure gradient, it is found that local shear has an important effect on the stability of elongated plasmas, and that stability deteriorates through high elongation since the stabilizing effects of field line bending and local shear are reduced. The net contribution of the local shear to stability decreases with elongation for strong ballooning modes (eigenfunctions strongly localized near the outer edge of the toroidal flux surfaces) but increases for interchange modes (eigenfunctions more uniform along the flux surfaces). – The computational study of high-n ballooning modes in a highly elongated plasma reveals that lowering the aspect ratio and broadening the pressure profile enhance the marginal beta for βp less than unity but severely reduce the marginal beta for βp larger than unity.
Tensile Fracture Toughness of Ceramic Materials: Effects of Dynamic Loading and Elevated Temperatures

Experimental methods are presented for the determination of fracture initiation toughness of ceramics and ceramic composites in pure tension under quasi-static and dynamic loading conditions over a range of temperature spanning 20° to 1300°C. Circumferentially notched and cyclic fatigue precracked rods of a variety of ceramic materials were subjected to quasi-static tensile fracture (rate of stress intensity factor loading, K1∼ 0.1 MPa ∼ m1/2∼ s−1) in an electroservohydraulic test machine and to dynamic tensile fracture (K1∼ 106 MPa ∼ m1/2· s−1) using a modified tensile Kolsky (split-Hopkinson) bar. For the quasi-static and dynamic fracture tests at elevated temperatures, the ceramic specimen was inserted into an air furnace where either friction grips or stress wave loading outside the furnace subjected the specimen to fracture. Dynamic finite-element analyses of the circumferentially notched cylindrical rod have been conducted to develop the optimum specimen dimensions and test procedures for the measurement of dynamic fracture toughness at ambient and elevated temperature. Experiments conducted on Al2O3, Si3N4, and SiC, and an Al2O3-25 vol% SiC whisker composite at room temperature indicate that the dynamic to quasistatic fracture initiation toughness ratio KId/KIc is in the range of 1.1 to 1.4. Elevated-temperature fracture tests for the polycrystalline Al2O3 of 3-μm average grain size reveal that KId is only mildly sensitive to temperature over a range of 20° to 1100°C, whereas it suffers a precipitous drop above 1100°C. Over the temperature range 20° to 1300°C, the ratio KId/KIc is found to be in the range 1.2 to 1.5. Scanning electron microscopy observations show that failure above 1100°C usually evolves by the nucleation, growth, and coalescence of cavities. The mechanisms of elevated-temperature quasi-static and dynamic fracture in polycrystalline Al2O3 are examined and possible causes for the apparently higher dynamic fracture initiation resistance are discussed. The significance and limitations of the proposed experimental techniques are highlighted.
Study of the double-resonance ionization spectrum of indium with emphasis on the resonance detection of photons

Abstract The double-resonance ionization spectrum of indium has been recorded in an air/acetylene flame. The first step in the double-resonance scheme was tuned to the 303.94 nm resonance transition of In between the ground state and the 5 d 2 D 3/2 excited state. The double-resonance ionization spectrum was obtained by scanning a second laser in the wavelength range 740–796 nm. A total of 29 transitions were observed and identified. The observed transitions have been assigned to the three principal series: 5 d 2 D → nf 2 F , 6 p 2 P → nd 2 D and 6 p 2 P → ns 2 S . The latter two series originate in an atomic energy level of In that is collisionally populated from the laser pumped 5 d 2 D states. The transition 6 p 2 P 3/2 → 10 d 2 D 5/2 was subsequently studied as the second step in a resonance ionization photon detector (RID). Figures of merit for the RID based on the detection of photons at 303.94 nm are presented. A quantum efficiency of 0.76 electrons/photon and a minimum detectable number of photons of 1600 were found for the selected scheme.
Heterogeneous β2-Adrenoceptor Expression and Dilation in Coronary Arterioles Across the Left Ventricular Wall

Background— Previous in vivo studies have shown that β-adrenoceptor agonists cause a redistribution of coronary flow away from the subendocardium; however, the underlying mechanism remains uncertain. We tested the hypothesis that a heterogeneous distribution of β-adrenoceptors and their vasomotor responses exists in the coronary microcirculation across the left ventricular wall. Methods and Results— Porcine subepicardial and subendocardial arterioles (<100 μm) were isolated from the left ventricle and pressurized for in vitro study of vasodilation to the nonselective β-adrenoceptor agonist isoproterenol and the selective β2-adrenoceptor agonist procaterol. Both vessel types developed a similar level of basal tone and dilated to isoproterenol and procaterol. However, subepicardial arterioles exhibited a much higher sensitivity and greater dilation capacity to both agonists. The isoproterenol-induced vasodilations were inhibited by glibenclamide, an ATP-sensitive potassium (KATP) channel blocker. In contras...
A Novel G418 Conjugate Results In Targeted Selection of Genetically Protected Hepatocytes without Bystander Toxicity

G418, an aminoglycoside neomycin analogue, is an antimicrobial agent that interferes with protein synthesis and has been used extensively for selection of mammalian cell lines that possess neomycin resistance (NR). It is potent and nonspecific in its effects that occur through tight binding to ribosomal elements. Because of the potent intracellular effect, we wondered whether G418 could be used to select a specific cell type based on receptor-mediated endocytosis. The objective of this study was to target G418 specifically to liver cells via asialoglycoprotein receptors (AsGR) which are known to be highly selective for these cells. A novel G418 conjugate was synthesized chemically by coupling G418 to a galactose-terminating carrier protein, asialoorosomucoid (AsOR), in a molar ratio of 5:1. AsOR-G418 conjugates inhibited viability of AsGR (+) cells by 84.3%, while inhibition in AsGR (-) cells was only by 19%. In AsGR (+) cells, stably transfected with a NR gene, the conjugate decreased viability by less than 9%. Furthermore, incubation of conjugate in cocultures of AsGR (+), and AsGR (-) cells did not result in the loss of viability of neighboring AsGR (-) cells. Our data demonstrate for the first time that G418 can be covalently bound to AsOR to form a conjugate for hepatocyte-specific targeting and toxicity. AsOR-G418 conjugates may be useful tools for genetic manipulation of human liver cells in the presence of nonhepatic cells.
A Bicycle Computer

In an ettort to reduce system developrment time, system costs and to provide more capabilities, system designers have turned more and more to microcomputers. The microcomputer (MCU), in adclition to containing a CPU, usually contains ROM, RAM, TIMERS, I/O and other teatures. Because of these basic building blocks, integrated onto a tiny piece ot silicon, the MCU can be described as a "System on Siilicon". Hence the phrase is often heard "the system is tne solution". The microcomputer because it is an extremely powerful mass produced system, that is easily adaptable, to specitic tasks, makes it the basic building block of many larger system tasks. (applications)
Raman spectra of polycrystalline acetone and acetone-d6

The Raman spectra of polycrystalline acetone and acetone-d6 were recorded from 150 to 4000 cm−1. A number of the methyl vibrations that are obscured in the spectra of gaseous and liquid phase samples are assigned on the basis of the spectra of the solid films. The interesting a2 and b2 torsional vibrations are tentatively assigned to bands at 112 and 130 cm−1, respectively, in the spectrum of solid acetone. These frequencies are not directly observed, but are inferred from the appearance of weak combination bands believed to involve the two torsional modes and the a1 skeletal bending vibration.
Synchrotron radiation calculations using the EGS4 code

Abstract Distributions of synchrotron radiation intensity as a function of photon energy and opening angle are complicated which, together with elaborate geometries, make the Monte Carlo technique the method of choice for most synchrotron radiation calculations. This paper presents synchrotron radiation calculations using the EGS4 Monte Carlo code. Two examples related to the SLAC PEP-II project are given. The first is the calculation of the dose to the magnet coil insulation from synchrotron radiation escaping the stainless steel vacuum chamber in the straight sections of the High Energy Ring. Emphasis is given on the spectral sampling and the normalization of the Monte Carlo dose results. The second is the calculation of the dose environment in the tunnel resulting from synchrotron radiation escaping the aluminum vacuum chamber and antechamber of the Low Energy Ring with emphasis on the opening-angle profile.
Thyroxine and the Release of Protein fromRat Liver Mitochondria

Thyroactive compounds at concentrations down to 5 × 10−6 M have the property of decreasing the amount of protein released by rat liver mitochondria in a suspending medium of either sucrose or phosphate at pH 7.4. This reaction is marked after 30 minutes at 37 C but is detectable at 25 C. A small amount of protein is released during the phase of rapid swelling produced by thyroid hormones, but thereafter the protein content of the suspending medium remains almost constant. By contrast, the delayed swelling noted in solvent controls is accompanied by continuous release of larger amounts of protein. Both magnesium ions and ATP at high concentrations affect the reaction in a complex manner, decreasing the release of protein in the solvent controls, an effect that is antagonized by the thyronines. These findings may be related to the preservation by thyronines of the failing metabolic systems of isolated tissues.
Cancellous Bone Properties and Matrix Content of TGF-β2 and IGF-I in Human Tibia: A Pilot Study

Transforming and insulin-like growth factors are important in regulating bone mass. Thus, one would anticipate correlations between matrix concentrations of growth factors and functional properties of bone. We therefore investigated the relationships of (1) TGF-β2 and (2) IGF-I matrix concentrations with the trabecular microstructure, stress distribution, and mechanical properties of tibial cancellous bone from six male human cadavers. Trabecular stress amplification (VMExp/σapp) and variability (VMCOV) were calculated using microcomputed tomography (μCT)-based finite element simulations. Bone volume fraction (BV/TV), surface/volume ratio (BS/BV), trabecular thickness (Tb.Th), number (Tb.N) and separation (Tb.Sp), connectivity (Eu.N), and anisotropy (DA) were measured using 3-D morphometry. Bone stiffness and strength were measured by mechanical testing. Matrix concentrations of TGF-β2 and IGF-I were measured by ELISA. We found higher matrix concentrations of TGF-β2 were associated with higher Tb.Sp and VMExp/σapp for pooled data and within subjects. Similarly, a higher matrix concentration of IGF-I was associated with lower stiffness, strength, BV/TV and Tb.Th and with higher BS/BV, Tb.Sp, VMExp/σapp and VMCOV for pooled data and within subjects. IGF-I and Tb.N were negatively associated within subjects. It appears variations of the stress distribution in cancellous bone correlate with the variation of the concentrations of TGF-β2 and IGF-I in bone matrix: increased local matrix concentrations of growth factors are associated with poor biomechanical and architectural properties of tibial cancellous bone.
Circadian rhythm of neurotensin levels in rat small intestine

Abstract The present studies were undertaken to determine whether a 24 h rhythm occurs in neurotensin (NT) levels in the small intestine of the rat and if so, whether the rhythm depends upon the 24 h cycles of light or feeding. A total of 145 male rats were sacrificed at 4 h intervals and the levels of neurotensin-like immunoreactivity (NTLI) in the middle 30 cm of small intestine were determined by radioimmunoassay with region specific antisera. There was a significant ( P ) 24 h rhythm in the levels of NTLI in groups of rats maintained under constant illumination or a 12:12 light:dark cycle and fasted for either 24 h or provided food ad libitum. Levels of NTLI ranged from 50 to 140 pm/g and were highest during the early morning (0400–0800 h) and lowest during the afternoon (1200–1600 h). The NTLI from samples taken at 0400 and 1600 h was subjected to high-performance liquid chromatography. The levels of chromatographically and immunochemically characterized NT were consistent with the levels of NTLI, evidence that the 24 h variation in NTLI most likely reflects changes in the intestinal content of NT and not other substances with similar immunochemical properties.
Fixation of mandibular angle fractures with a 2.0-mm 3-dimensional curved angle strut plate.

Purpose The aim of this study was to evaluate our experience and complication rate with the use of a 3-dimensional 2.0-mm curved angle strut plate for mandibular angle fracture fixation. Patients and methods This was a retrospective evaluation of 37 patients with noncomminuted mandibular angle fractures fixated with a transorally placed curved 2.0-mm strut plate. Postoperative intermaxillary fixation was used in 5 patients for a mean period of 22 days. A nonchewing diet was prescribed for 6 weeks. Records were reviewed for demographic information, medical history, fracture characteristics, operative management, and complications. Results Two patients developed infections requiring plate removal and reapplication of fixation. Both of these patients had a molar in the fracture line that was left in place during the first operation. One patient developed a mucosal wound dehiscence without consequence. After a mean follow-up period of 10 weeks, 39.4% of patients with a postinjury/pretreatment inferior alveolar nerve deficit reported a return to normal sensation. All patients who developed a sensory deficit as a result of surgery reported full recovery of sensation. A persistent sensory deficit appeared to be related to fracture displacement. Conclusion Fixation of noncomminuted mandibular angle fractures with a 2.0-mm curved angle strut plate was predictable. This plate is low in profile, strong yet malleable, facilitating reduction and stabilization at both the superior and inferior borders. Development of a postoperative infection appeared to be related to failure of removal of a molar in the fracture line. The infection rate of 5.4% found in this study compares favorably with that seen with reconstruction plates. Use of this plate did not appear to cause a permanent sensory deficit in this study.
Ventilating systems for railway traction equipment

IN THE EARLY STAGES of the development of railway traction equipment the need for some form of ventilation became evident. This need increased with the continuing demand for increased output. As a result, cooling systems evolved from self- to forced ventilation. Their development was not, however, an unmixed benefit. Any ventilation tends to draw dirt, snow, moisture, and other contaminants into the machine, with harmful results. The undesirable effects may be reduced by design measures aimed at the following: 1. making the components more resistant to damage, 2. preventing the accumulation of foreign matter in critical locations, and 3. cleaning the air before it enters the machines The proper measures to employ in a given instance are determined by design, practical and economic consideration.
COMBUSTION OF LITHIUM–ALUMINUM ALLOYS

ABSTRACT The combustion of lithium–aluminum alloys was investigated by experiment and with a computational flame model. Five Li–Al alloy compositions were studied experimentally, ranging from pure Li to 26 wt% Li/74 wt% Al. Alloy samples were heated inductively in a crucible to temperatures ranging from 1000 to 1400 K and burned with oxygen/argon mixtures or with water vapor in a counterflow diffusion flame. Flame temperature profiles were measured using a Li resonance line reversal method, and relative lithium atom populations in the flame were determined using an absorption method. The products of combustion, analyzed using x-ray diffraction and field-emission scanning electron microscopy/energy dispersive x-ray spectroscopy, are Li2O, γ-LiAlO2, and β-Li5AlO4, with some solid LiOH produced during combustion in water vapor. Although aluminum monoxide gas was detected at ignition in water vapor in a limited number of tests, evidence indicates that aluminum does not burn in the vapor phase during steady-st...
Physical and Psychosocial Correlates of Test-Retest Isometric Torque Variability in Patients with Chronic Low Back Pain

Variability in trunk torque production has been suggested as a means of detecting submaximal effort in the assessment of chronic low back pain. Several investigations question the validity of using torque variability to detect submaximal efforts in patients with back injuries. However, few investigations have studied the correlates of text-retest torque variability in clinical populations. The present study investigated psychological distress, disability/flexibility/pain, and symptom magnification correlates of test-retest torque variability in chronic low back pain patients. Contrary to previous studies, psychological distress, tendency to report symptoms, and pain were negatively correlated with measures of torque variability. The findings indicate the potential for psychological variables to influence torque production, but on the whole provide little strong support for the use of test-retest torque variability as a means of detecting submaximal performance.
Wnt Signaling Polarizes an Early C. elegans Blastomere to Distinguish Endoderm from Mesoderm

Abstract A polarizing signal induces endoderm production by a 4-cell stage blastomere in C. elegans called EMS. We identified 16 mutations in five genes mom-1 through mom-5 , required for EMS to produce endoderm. mom-1, mom-2 , and mom-3 are required in the signaling cell, P 2 , while mom-4 is required in EMS. P 2 signaling downregulates an HMG domain protein, POP-1, in one EMS daughter. The sequence of mom-2 predicts that it encodes a member of the Wnt family of secreted glycoproteins, which in other systems activate HMG domain proteins. Defective mitotic spindle orientations in mom mutant embryos indicate that Wnt signaling influences cytoskeletal polarity in blastomeres throughout the early embryo.
Widespread intracerebral metastases from prostate adenocarcinoma.

A 62-year-old man with prostate cancer and pulmonary metastases presented with a partial-onset seizure, involving a forced leftward head deviation and tonic limb posturing. He complained of no other symptoms except for diplopia. On examination, there was mild bilateral papilloedema, bilaterally limited ocular abduction, left-sided ataxia and bilateral extensor plantar responses. His medical history included two previous cerebellar infarctions, presumed to be due to cancer-related hypercoagulability and a completely resected cutaneous melanoma. MR scan of the brain showed multiple cystic and nodular enhancing intraparenchymal lesions, some containing blood …
Potential role of PKR in double‐stranded RNA‐induced macrophage activation

In this study, the role of the double-stranded (ds) RNA-dependent protein kinase (PKR) in macrophage activation was examined. dsRNA [polyinosinic:polycytidylic acid (poly IC)]-stimulated inducible nitric oxide synthase, interleukin (IL)-1α and IL-1β mRNA expression, nitrite formation and IL-1 release are attenuated in RAW264.7 cells stably expressing dominant negative (dn) mutants of PKR. The transcriptional regulator nuclear factor (NF)-κB is activated by dsRNA, and appears to be required for dsRNA-induced macrophage activation. While dnPKR mutants prevent macrophage activation, they fail to attenuate dsRNA-induced IκB degradation or NF-κB nuclear localization. The inhibitory actions of dnPKR on dsRNA-induced macrophage activation can be overcome by treatment with interferon (IFN)-γ, an event associated with PKR degradation. Furthermore, dsRNA + IFN-γ stimulate inducible nitric oxide synthase expression, IκB degradation and NF-κB nuclear localization to similar levels in macrophages isolated from PKR–/– and PKR+/+ mice. These findings indicate that both NF-κB and PKR are required for dsRNA-induced macrophage activation; however, dsRNA-induced NF-κB activation occurs by PKR-independent mechanisms in macrophages. In addition, the PKR dependence of dsRNA-induced macrophage activation can be overcome by IFN-γ.
Operation of a long-pulse relativistic magnetron in a phase-locking system

Successful injection-locking of relativistic magnetrons requires frequency stable microwave output with pulse lengths longer than the phase-locking time. We report the major experimental results from our stable and long-pulse relativistic magnetron system designed to address important issues relevant to the realization of injection-locking. Long voltage pulse operation 1js) with good stability was achieved and relatively long (250 ns) RF pulses at 5 MW output power level were generated. These pulses exceed the theoretical locking time for a 1 MW injected power source. The magnetron operates in S-band (3. 66 GHz) and is driven by a modulator which operates either at 700 kV/ 700 A or 250 kV/ 1. 7 kA. The stability of the narrow band microwave frequency is better than 3 parts in 1000. Possible RF pulse-shortening mechanisms are studied. 1.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A comparative study of the crosslinking precursors present in rat skin and tail tendon collagen.

Tissue specific differences in the amounts and the location of aldehyde groups have been observed which are directly related to the solubility characteristics of collagen, extent of maturation and the functional role of the tissue. Whereas the aldehydes are restricted to the N-terminal region of rat tail tendon collagen, in skin they are also present in the helical region of the molecule and are able to participate in the formation ofstableinter-molecular crosslinks.
Computational study of reacting flow establishment in expansion tube facilities

We study the temporal evolution of the combustion flowfield established by the interaction of ram accelerator-type projectiles with an explosive gas mixture accelerated to hypersonic speeds in an expansion tube. The Navier-Stokes equations for a chemically reacting gas mixture are solved in a fully coupled manner using an implicit, time accurate algorithm. The solution procedure is based on a spatially second order, total variation diminishing scheme and a temporally second order, variable-step, backward differentiation formula method. The hydrogen-oxygen-argon chemistry is modeled with a 9-species, 19-step mechanism. The accuracy of the solution method is first demonstrated by several benchmark calculations. Numerical simulations of expansion tube flowfields are then presented for two different geometries: an axisymmetric projectile and a ram accelerator configuration. The development of the shock-induced combustion process is followed. The temporal variations of the calculated thrust and drag forces on the ram accelerator projectile are also presented. In the axisymmetric projectile case, which was designed to ensure combustion only in the boundary layer, the radial extent of the flame front during the initial transient phase was surprisingly large. In the ram accelerator configuration the flame propagated upstream along both the projectile and tube wall boundary layers, resulting in unstart.
G1 specific increases in cyclic AMP levels and protein kinase activity in Chinese hamster ovary cells.

Abstract Chinese hamster ovary cells were synchronized by selective detachment of cells in mitosis. The adenosine 3′:5′-cyclic monophosphate (cyclic AMP) intracellular concentrations and cyclic AMP-dependent protein kinase activities were measured as these cells traversed G 1 phase and entered S phase. Protein kinase activity, assayed in the presence or absence of saturating exogenous cyclic AMP in the reaction mixture, was lowest in early G 1 phase (2 h after mitosis), increased 2-fold (plus exogenous cyclic AMP in reaction mixture) or 3.5-fold (minus cyclic AMP in reaction mixture) to maximum values in mid to late G 1 phase (4–5 h after mitosis), and then decreased as cells entered S phase. Intracellular cyclic AMP concentrations were minimal 1 h after mitosis, increased 5-fold to maximum levels at 4–6 h after mitosis, and decreased as cells entered S phase. Similar to the fluctuations in intracellular cyclic AMP, the cyclic AMP-dependent protein kinase activity ratio increased more than 40% in late G 1 or early S phase. Puromycin (either 10 μg/ml or 50 μg/ml) administered 1 h after mitosis inhibited cyclic AMP-dependent protein kinase activity up to 50% by 5 h after mitosis, while similar treatment (10 μg/ml) had no effect on the increase in cyclic AMP formation. These data demonstrate that: (1) total protein kinase activity changed during G 1 phase and this increase was dependent on new protein synthesis; (2) the increased intracellular concentrations of cyclic AMP were not dependent on new protein synthesis; and (3) the activation of cyclic AMP-dependent protein kinase was temporally coordinated with increased intracellular concentration of cyclic AMP as Chinese hamster ovary cells traversed G 1 phase and entered S phase. These results suggest that cyclic AMP acts during G 1 phase to regulate the activation of cyclic AMP-dependent protein kinase.
Simultaneous homoharringtonine and interferon-α in the treatment of patients with chronic-phase chronic myelogenous leukemia

BACKGROUND Homoharringtonine (HHT) has antileukemic activity in patients with Philadelphia chromosome (Ph) positive chronic myelogenous leukemia (CML). Combinations of HHT, interferon-α (IFN-α), and cytarabine (ara-C) have been studied in various CML phases. The objectives of this study were to evaluate the efficacy and toxicity profiles of a combination regimen of simultaneous HHT and IFN-α therapy in patients with chronic-phase CML who were not exposed previously to either agent. METHODS Forty-seven patients were treated: 37 patients with early chronic-phase CML (2 patients with clonal evolution) and 10 patients with late chronic-phase CML. Their median age was 62 years (range, 23–73 years). HHT was given at a dose of 2.5 mg/m2 by continuous intravenous infusion over 24 hours daily for 5 days every month, and IFN-α was given daily at a target dose of 5 × 106 units/m2 subcutaneously. Response, survival, and treatment toxicity were analyzed. RESULTS Overall, the complete hematologic response (CHR) rate was 85%; the cytogenetic response rate was 66%, with major cytogenetic responses (Ph positive in 60 years were 84%, 62%, and 49% for CHR, cytogenetic response, and major cytogenetic response. Myelosuppression was frequent but manageable: Anemia with hemoglobin < 8.0 g/dL occurred in 36% of patients, requiring dose adjustments and erythropoietin therapy. Nonhematologic toxicities were mainly fatigue, aches, and gastrointestinal disturbances. Dose reductions with multiple courses were significant and were due to myelosuppression: After 6–24 courses, the median daily IFN-α dose was 1 MU/m2, and the median number of days on HHT per month was 2 days. With a median follow-up of 26 months, the estimated 2-year survival rate was 90% (95% confidence interval, 79–100%). CONCLUSIONS The simultaneous combination of HHT and IFN-α is safe and effective, but the dose schedules that actually were delivered were significantly lower than the planned dose schedules. With the availability of signal-transduction inhibitor 571 (imatinib mesylate), studies of combination of HHT and IFN-α chemotherapy in patients with CML who have disease that fails to respond to imatinib mesylate and of combinations with imatinib mesylate need to be explored. Cancer 2002;94:2024–32. © 2002 American Cancer Society. DOI 10.1002/cncr.10436
Multiple-changepoint testing for an alternating segments model of a binary sequence.

Summary. A binary sequence may give the appearance of being composed of alternating segments with relatively high and relatively low probability of success. Determining whether such an alternating pattern is significant is a multiple-changepoint problem where the number of segments and their success probabilities are unknown, with the added constraint of segment alternation. A dynamic programming method for determining the optimal segmentation into a given number of segments is provided. Given this, a variation on the simulation method of Venter and Steel (1996, Computational Statistics and Data Analysis22, 481–504) may be employed t o test the null hypothesis of a homogeneous sequence as well as to estimate the number and location of changepoints. A sample application, the assessment of the possibility of genetic recombination in HIV sequences, is presented.
Local measurement of venous saturation in tissue with noninvasive near-infrared respiratory oximetry

We present preliminary results of non-invasive, near-infrared measurements of venous saturation (SvO2) on the leg muscle of three anesthetized piglets. We have quantified the local SvO2 by analyzing the optical spectrum of the amplitude of the absorption oscillations synchronous with breathing. To induce a variation in the muscle SvO2, we performed measurements during a protocol involving a cyclic change in the fraction of oxygen inspired by the piglet over the range 10-100% (by volume). In all three piglets, we have found a good agreement between the SvO2 values measured non-invasively with near-infrared spectroscopy (NIRS) and those measured invasively by the analysis of venous blood samples.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A Human Factors Comparison of Three Cargo Trucks

As part of a U.S. Army field test, three cargo trucks and three truck-tractors were compared on a number of human factors variables. Among the variables were noise level in the passenger compartment and ride quality at the driver's seat. Ride quality was measured in terms of the energy absorbed by the driver as the vehicle traveled over a specified terrain profile at a specified speed. The vehicles were judgmentally evaluated by a sample of 23 drivers on 35 other human factor variables in the categories of adequacy of driver compartment; visibility; instruments; controls; steering, braking and shifting; and ride. Differences were found among the vehicles on most of the variables. Language: en
What do we mean by rationality

The central task of public choice over the next twenty-five years will be a critical exploration of the behavioral assumption it employs. A dissection of the rationality assumption is essential in order to incorporate much more “realistic” assumptions to be derived from the diverse mental models that guide human decision-making. Does such a dissection make a difference to our models? You bet. If individuals have different theories to explain the world around them, they will make different “rational” choices. Ideas matter. As Frank Hahn (1987: 324) succinctly put it, “There is a continuum of theories that agents can hold and act upon without ever encountering events which lead them to change their theories.” In such circumstances there is not one equilibrium but multiple equilibria. In this brief essay I intend to support the above assertions.
Effects of lindane on steroidogenesis and steroidogenic acute regulatory protein expression.

Abstract Lindane, the γ isomer of hexachlorocyclohexane (HCH), is one of the oldest synthetic pesticides still in use worldwide. Numerous reports have shown that this pesticide adversely affects reproductive function in animals. Although the pathogenesis of reproductive dysfunction is not yet fully understood, recent reports indicate that lindane can directly inhibit adrenal and gonadal steroidogenesis. Because Leydig cells play a pivotal role in male reproductive function through the production of testosterone, the mouse MA-10 Leydig tumor cell line was used to assess the potential effects of γ-HCH and its isomers, α-HCH and δ-HCH, on steroid production, steroidogenic enzyme expression and activity, and steroidogenic acute regulatory (StAR) protein expression. StAR mediates the rate-limiting and acutely regulated step in hormone-stimulated steroidogenesis, the intramitochondrial transfer of cholesterol to the P450scc enzyme. Our studies demonstrate that α-, δ-, and γ-HCH inhibited dibutyryl ([Bu]2) cAMP-...
Sensitivity Analysis and Improved Identification of a Systemic Arterial Model

An identification scheme for the determination of several parameters associated with a third-order lumped-parameter model of the systemic arterial system has been developed previously [1]. In the present study a parameter sensitivity analysis of this model is conducted in conjunction with the identification scheme. This analysis indicates that the state variables of this system are indeed sensitive to changes in the model parameters and initial conditions, but not unduly so. It also indicates the relative sensitivities of individual model parameters and provides valuable insight into the behavior of the arterial model. This insight has resulted in a significant simplification and modification of our identification scheme [1] that makes it more likely to be employed in practice.
Outcome of All-Inside Second-Generation Meniscal Repair: Minimum Five-Year Follow-up

Background:Meniscal repair and preservation are the goal, when possible, of the treatment of meniscal injury. Current research on second-generation all-inside repair systems has been limited to a maximum of three years of follow-up. The purpose of this study was to evaluate the mid-term clinical suc
Nanoreactor Engineering for Life Sciences and Medicine (Ostafin, A. and Landfester, K.; 2009) [Book Review]

This book offers coverage of the design of nanoreactors, providing full details on the research, synthesis, and characterization of these systems. A handful of potential applications in cell biology, tissue engineering, and medical diagnostics and therapies are presented. Readers with strong chemistry, biology, and medical backgrounds will find a useful collection of techniques in designing nanoreactors for biomedical applications.
Geology and the loessial soils, Tell Jemmeh, Israel

Tell Jemmeh (Tell Re'im) is in the climatically sensitive transitional zone between the southern Coastal Plain of Israel and the northwestern Negev. It is a major site that was inhabited from about 3500 to 200 B.C. with an occupation gap between ca. 3100 and 1800 B.C., possibly a result of a particularly dry period. Quaternary loess derived by winter dust storms from the Sinai and Sahara and reworked loess blanket the region. Imposed on these are well-developed Holocene and Quaternary pedocal profiles that have been identified in the field and substantiated in the lab by variations in bulk chemical composition, petrography, and mineralogy by X-ray diffraction. Pluvial events are evidenced by dark-colored A-horizons high in clay minerals, Al2O3, and Fe2O3 and by periods of loess accumulation. Interpluvials and the Holocene commonly involved wind ablation and water erosion, and led to shallow depths with very high-calcite B-horizons. Some of the loessial soil horizons were found to be suitable ceramic clays, and their composition and petrography provide a basis for distinctions between locally made and imported ceramics, as well as to identifying modifications of local clay resources by potters.
Doubly nonlinear parabolic equations with singular lower order term

Abstract In this paper we are concerned with positive solutions of the doubly nonlinear parabolic equation u t =div( u m −1 |∇ u | p −2 ∇ u )+ Vu m + p −2 in a cylinder Ω×(0,T) , with initial condition u (·,0)= u 0 (·)⩾0 and vanishing on the parabolic boundary ∂Ω×(0,T) . Here Ω⊂ R N (resp. H n ) is a bounded domain with smooth boundary, V∈L loc 1 (Ω) , m∈ R , 1 p N and m + p −2>0. The critical exponents q ∗ are found and the nonexistence results are proved for q ∗ ⩽m+p .
The relationship between safety belt usage as observed in selected California communities and belt configuration in the vehicle

Abstract In the fall of 1971, safety belt usage (lap belt only or lap/shoulder combination) was observed for more than 9000 front seat occupants of certain late model automobiles in three medium-sized communities in California. Vehicles were observed in low speed and high speed driving situations and observations recorded accordingly. Data were obtained for Chrysler. Ford and General Motors passenger cars for model years 1968–1971. Belt configuration is defined across three design variables—(a) push-button vs lift-latch buckle; (b) manual vs automatic belt adjustment; and (c) three-point vs four-point belt. It does not appear that belt usage is a function of vehicle age or manufacturer. Moreover, at the 5 per cent significance level, only one of the 12 relevant tests supports the hypothesis that usage is a function of belt configuration. One additional test supports this hypothesis at the 10 per cent significance level.
Kaon-Nucleon Total Cross Sections from 0.36 to 0.72 GeV/ c

The ${K}^{+}$ and ${K}^{\ensuremath{-}}$ total cross sections were measured on both hydrogen and deuterium at a series of momenta between 360 MeV/c and 720 MeV/c by the transmission method. The data were corrected for Coulomb and decay effects, and the isospin states were extracted. The ${K}^{+}N$, $I=0$ cross section was found to be free from resonances, although the presence of a small dip at about 700 MeV/c was confirmed. No convincing evidence was found for structure in the ${K}^{+}N$, $I=0$ cross section, which was observed to be steeply rising with increasing momentum throughout this range. The prominence of the ${\ensuremath{\Lambda}}^{\ensuremath{'}}(1520)$ was verified in the ${K}^{\ensuremath{-}}N$, $I=0$ system in which no additional structure was seen. In the ${K}^{\ensuremath{-}}N$, $I=1$ system no new structure was clearly established, though there appears to be a small enhancement with a mass about 1600 MeV.
Watchboard: curated microblogging for the enterprise

Traditional microblogging in the enterprise is known to increase work environment awareness, but is also coupled with information overload and privacy issues. We address these challenges by introducing the concept of curated microblogging, which proposes the addition of social curation and access control to such platforms. We also present Watchboard, a prototype tool incorporating these ideas, and discuss highlights of a preliminary user study delineating crucial factors of the proposed concept.
PCB metabolism in rats following prolonged exposure to Aroclor 1242 and aroclor 1016.

Several mono- and dihydroxy metabolites of ditri, and tetrachlorobiphenyl have been identified in the urine of rats fed prolonged diets of Aroclor 1016 or Aroclor 1242. Combined gas chromatography-mass spectrometry was used for characterization of the metabolic products.
Feasibility of using the scattering of laser light by a colloidal solution as a primary fluorescence standard

Abstract Light scattering by a colloidal solution is known to provide a means for calibrating the intensity of fluorescence emission. Suitable instrumentation is required in order to test the relationship between scattering and emission precisely, or to use scattering as a definitive primary standard. Ideal requirements for instrumentation might be met if a laser were used for excitation and the detector included a high-resolution double monochromator. To test the feasibility of developing such an instrument, a preliminary demonstration was carried out. Fluorescence was excited with an argon laser. The double monochromator detector was preset for the required wavelength resolution. The results show that an ideal combination of signal/noise ratio, wavelength resolution, and other exacting characteristics can be achieved. It appears that such an instrument can be used to develop laser light scattering by a colloidal solution as a definitive fluorescence standard.