cssi/SciSciGPT-SciSciNet huggingface dataset:
Application of data mining tools for classification of protein structural class from residue based averaged NMR chemical shifts

Abstract The number of protein sequences deriving from genome sequencing projects is outpacing our knowledge about the function of these proteins. With the gap between experimentally characterized and uncharacterized proteins continuing to widen, it is necessary to develop new computational methods and tools for protein structural information that is directly related to function. Nuclear magnetic resonance (NMR) provides powerful means to determine three-dimensional structures of proteins in the solution state. However, translation of the NMR spectral parameters to even low-resolution structural information such as protein class requires multiple time consuming steps. In this paper, we present an unorthodox method to predict the protein structural class directly by using the residue's averaged chemical shifts (ACS) based on machine learning algorithms. Experimental chemical shift information from 1491 proteins obtained from Biological Magnetic Resonance Bank (BMRB) and their respective protein structural classes derived from structural classification of proteins (SCOP) were used to construct a data set with 119 attributes and 5 different classes. Twenty four different classification schemes were evaluated using several performance measures. Overall the residue based ACS values can predict the protein structural classes with 80% accuracy measured by Matthew correlation coefficient. Specifically protein classes defined by mixed αβ or small proteins are classified with > 90% correlation. Our results indicate that this NMR-based method can be utilized as a low-resolution tool for protein structural class identification without any prior chemical shift assignments.
HALOGENS ADSORBED ON MOLYBDENUM: THEIR SURFACE LIFETIMES AND DESORPTION KINETICS.

Abstract The surface lifetimes of fluorine, chlorine, bromine and iodine adsorbed on a molybdenum surface have been obtained from measurements of the halide ion desorption flux using the modulated molecular beam technique. Measurements were made at temperatures between 1350 and 1850 K and at surface coverages of less than 1010 halogen atoms cm−2. The temperature-lifetime data were fitted to an Arrhenius expression from which the binding energies l, and pre-exponential factors τ0, were obtained: F: l = 4.65 eV and τ 0 = 3 × 10 −16 s ; Cl: l = 4.11 eV and τ 0 = 3 × 10 −16 s ; Br: l = 3.70 eV and τ 0 = 2 × 10 −15 s ; I: l = 3.15 eV and τ 0 = 1 × 10 −16 s . It was concluded that the halogens are adsorbed as strongly bound surface compounds, MoX (where X is either F, Cl, Br, or I) from which gaseous ions and neutral atoms desorb at rates consistent with the Saha-Langmuir relationship. From that relationship and the above data, separate binding energies and pre-exponentials were calculated for ion and neutral desorption. The importance of the desorption of MoX was assessed.
The Calibration of Heart Sound Intensity

There is no standardized method for the calibration of total energy conducted to the surface of the chest caused by the cardiac sounds. Loudness is a subjective term which is dependent upon total energy, frequency of the main components and the specific sensitivity of the human hearing mechanism. A method is described in which the amplitude of the chief component of the heart sounds is compared to that produced by a standard sound signal at 80 decibels at 500 cycles per second and an intensity ratio calculated. The method has been applied to normal individuals of different ages and to those with mitral valve disease and those with pulmonary hypertension. The findings confirm the clinical observation that mitral stenosis with persisting mobility of the valve leaflets is associated with a loud first heart sound. However, the measurement of intensity of the second heart sound did not show so reliable a correlation between the loudness of the sound and the pulmonary blood pressure. The relationship is somewha...
Inhibition of rat brainstem monoamine oxidase activity by CGP 6085 A

Abstract CGP 6085 A [4-(5,6-dimethyl-2-benzofuranyl) piperidine] HC1, a known serotonin inhibitor, also inhibits rat brainstem monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B) in both in vivo and in vitro experiments. Serotin (5-HT) deamination by MAO-A is inhibited 35% at a dose of 100 mg/kg i.p. in vivo . Similar experiments show a maximal 20% decrease in phenylethylamine (PEA) deamination by MAO-B at a dosage of 30 mg/kg i.p. Over the range of 0.1 to 10 mg/kg i.p., CGP 6085 A decreases 5-HIAA levels in the brainstem. This in vivo inhibition of MAO activity is confirmed by in vitro experiments. In vitro studies in rat brainstem mitochondrial preparations show a dose-dependent, reversible, inhibition of MAO using tyramine as the substrate for the enzyme reaction. With an in vitro IC50 of 2–3 μM, the potency of CGP 6085 A is comparble to pargyline.
The Prevalence of Nutritional Depletion and Nutritional Support of the Pediatric Intensive Care Unit Patient

Abstract Objective: The prevelence of nutritional depletion utilizing anthropometric measurements has been reported to be 20% in hospitalized pediatric patients upon admission. It has also been reported that the majority of pediatric patients in the intensive care unit (ICU) remain NPO by day 3 in the ICU. We hypothesize that there is a high incidence of nutritional depletion in our ICU pediatric patients upon admission as indicated by weight less than fifth percentile and that patients who have extended stays (> 5 days) in the ICU receive calories below our calorie recommendations. Methods: A prospective, observational study was conducted to investigate these hypotheses. Pediatric patients who remained in the ICU for greater than 5 days were evaluated for: weight, type of nutrition ordered, calories ordered, calories received, and calories recommended by the Parenteral and Enteral Nutrition (PEN) team. Results: Twenty-seven patients enrolled in the study between October and December, 1994. The study group consisted of 15 males and 12 females with ages ranging from 1 month to 19 years of age (X = 7.5 years). The majority of patients were admitted either to the pediatric medical service (n=9) or the pediatric surgical service (n=8). The average length of stay was 14.6 days (range 5–43 days). Eight patients (30%) were admitted with a weight less than the fifth percentile for age. An analysis of calories ordered and received was completed for each of the 18 patients receiving parenteral nutrition (TPN; n=7), tube feeding (TF; n=5) or a combination of TPN and TF (n=6). Physicians ordered calories equal to or greater than those recommended by the PEN team in 6 (33%) of the 18 patients. Physicians ordered an average of 87%± 33% of recommended calories (range 25–163%). The percent of ordered calories received by patients was 76% ± 14% (range 47–102%). Patients received 67% +28% of calories recommended by the PEN team (range 14–104%). Conclusion: Pediatric patients who remain in our ICU for greater than 5 days have a higher prevalence of nutritional depletion than reported in the literature (30% vs 20%). This study indicates that calories received by these patients are less than those recommended by the PEN team due to a combination of inadequate calorie ordering by physicians and frequent interruption of caloric delivery. This study suggests that physicians should be educated regarding ordering recommended calories for pediatric ICU patients.
Rheology of blood: Effect of dilution with various dextrans

Abstract The effect on blood viscosity of dilution with flow improver and plasma expander types of dextrans, in different proportions, was studied in a capillary viscometer. All experiments were performed on fresh heparinized dog blood. It was observed that dilution of blood with dextran 40 increases the blood viscosity. This viscosity is higher than the viscosity of blood alone or dextran alone. This finding suggests that the viscosity of the suspending medium is relatively about as important as the hematocrit in determining the viscosity of the whole suspension, contrary to a widely held impression.
Emerging pedagogy: teaching digital hypertexts in social contexts

Abstract Fluid texts such as digital texts and hyperfictions present users with both individual and social challenges. In the classroom, particularly, teachers should take advantage of the multiple aspects of narrative time constructed through hypertextual duration, frequency, and order. These challenges, or disjunctures, invite teachers and students into transformative moments, or rejunctures, within the context of the classroom. Based upon an ethnographic study of two college courses, I illustrate several of these opportunities as they subvert the dominant orders of textuality totalized by print-based culture and form an emergent pedagogy.
A computational approach for eliminating error in the solution of the location set covering problem

Abstract The location set covering problem continues to be an important and challenging spatial optimization problem. The range of practical planning applications underscores its importance, spanning fire station siting, warning siren positioning, security monitoring and nature reserve design, to name but a few. It is challenging on a number of fronts. First, it can be difficult to solve for medium to large size problem instances, which are often encountered in combination with geographic information systems (GIS) based analysis. Second, the need to cover a region efficiently often brings about complications associated with the abstraction of geographic space. Representation as points can lead to significant gaps in actual coverage, whereas representation as polygons can result in a substantial overestimate of facilities needed. Computational complexity along with spatial abstraction sensitivity combine to make advances in solving this problem much needed. To this end, a solution framework for ensuring complete coverage of a region with a minimum number of facilities is proposed that eliminates potential error. Applications to emergency warning siren and fire station siting are presented to demonstrate the effectiveness of the developed approach. The approach can be applied to convex, non-convex and non-contiguous regions and is unaffected by arbitrary initial spatial representations of space.
Influence of doping and solid solution formation on the thermoelectric properties of chalcopyrite semiconductors

Abstract We have investigated the influence of zinc doping on the thermoelectric properties of CuInTe2–CuGaTe2 solid solution alloys. Undoped end-member compounds display typical p-type semiconducting behavior, with a negative temperature coefficient of resistivity and large Seebeck coefficient. With zinc substituting for indium or gallium, the hole concentration is increased and the electrical transport behavior evolves into that of a degenerate semiconductor, with both electrical resistivity and Seebeck coefficient increasing with temperature up to the highest temperature measured. For undoped samples the thermoelectric power factor is maximized close to 750 K, while in doped specimens the maximum occurs at much lower temperature. Substitution of gallium for indium induces significant phonon scattering and thermal conductivity reduction below 500 K. The dimensionless figure of merit rises to above unity over a range of compositions in these chalcopyrite compounds, with optimized samples reaching a figure of merit of 1.3.
Correlation between a unilateral midbrain-pontine lesion and abnormalities of brain-stem auditory evoked potential

Abstract Brain-stem auditory evoked potentials (BAEPs) were evaluated over a 39 day period in a patient with a unilateral pontine-midbrain lesion verified by CAT scan and autopsy. Waves I, II and III were present on the side of lesion, whereas all 5 waves were present on the side opposite the lesion. The findings suggest that the BAEPs may be obtained with only an intact ipsilateral auditory pathway. Crossing fibers in the trapezoid body also appear to make contributions to the normal generation of wave V.
Increased Phospholipase C-Catalyzed Hydrolysis of Phosphatidylinositol-4,5-Bisphosphate and 1,2-sn-Diacylglycerol Content in Psoriatic Involved Compared to Uninvolved and Normal Epidermis

Evidence suggests that the phospholipase C/protein kinase C signal transduction system participates in the regulation of epidermal cell growth and differentiation. Psoriatic epidermis is characterized by hyperproliferation, defective differentiation, and inflammation. In this report, we have determined the activity of phospholipase C-catalyzed hydrolysis of phosphatidylinositol-4,5-bisphosphate (PIP2) and 1,2-diacylglycerol content in normal and psoriatic involved and uninvolved epidermis. 1,2-diacylglycerol is formed from phospholipase C-catalyzed hydrolysis of PIP2 and is the physiologic activator of protein kinase C. PIP2 hydrolysis was assayed in soluble and particulate fractions prepared from keratome biopsies of normal and psoriatic skin. Total lipids were extracted from normal and psoriatic epidermis and 1,2-diradylglycerol (a mixture of 1,2-diacylglycerol and 1-ether, 2-acyl-glycerol) quantitated by enzyme assay. Because 1,2-diacylglycerol is a more potent activator of protein kinase C, the relative proportions of 1,2-diacyl and 1-ether, 2-acylglycerol in uninvolved and involved psoriatic epidermis were determined. This was accomplished by separation of acetate derivatives of 1,2-diacylglycerol and 1-ether, 2-acyl-glycerol by thin layer chromatography. Soluble and membrane-associated phospholipase C-catalyzed PIP2 hydrolysis were increased 3.7 times (p less than 0.001) and 3 times (p less than 0.004), respectively, in psoriatic involved compared to uninvolved and normal epidermis. 1,2-diradylglycerol content was also significantly elevated (3 times, p less than 0.01) in psoriatic involved versus uninvolved and normal epidermis. Analysis of the acetate derivatives of 1,2-diradylglycerol in psoriatic uninvolved and involved epidermis revealed that 1,2-diacylglycerol was the major species (86% and 95%, respectively). There were no significant differences in either phospholipase C-catalyzed PIP2 hydrolysis or 1,2-diacylglycerol content between uninvolved and normal epidermis. 1,2-diacylglycerol purified from normal and involved psoriatic epidermis was capable of activating protein kinase C from normal epidermis in vitro. In epidermal slices, activation of protein kinase C by addition of 12-0-tetradecanoylphorbol-13-acetate and 1,2-diacylglycerol (1,2-dioctanoylglycerol) resulted in subsequently decreased protein kinase C activity, a process termed down-regulation. These data are consistent with the possibility that the elevation in lesional 1,2-diacylglycerol content may account, in part, for the previously reported reduction of protein kinase C activity in psoriasis (Horn, Marks, Fisher, et al: J Invest Dermatol 88:220-222, 1987).
The Room Temperature Crystal Structure of the Perovskite Pr0.5Sr0.5MnO3

Abstract Using both powder and single crystal neutron diffraction we have determined the room temperature structure of Pr0.5Sr0.5MnO3from melt-grown crystalline material. Contrary to previous measurements on polycrystalline samples we find the room temperature structure of Pr0.5Sr0.5MnO3is tetragonal, space groupF4/mmc(a= 7.64093(5) A,c= 7.79104(8) A). The structure of Pr0.5Sr0.5MnO3is related to the ideal primitive cubic perovskite structure by a single correlated rotation of MnO6octahedra about thecaxis. We find that MnO6octahedra exhibit a small Jahn–Teller distortion (Δ(Mn–O) ≈ 0.02 A).
Characteristic linear dynamics of kinetically controlled burning. Part I: Traditional single-reactor models

We examine combustion controlled predominantly by chemical kinetics using various incarnations of the well-stirred reactor. The model is presented in canonical forms exhibiting first- and higher-order responses to both flow rate and mixing perturbations. These behaviors are completely characterized by physically relevant dimensionless quantities. Furthermore, because of their relevance to thermo-acoustic instabilities, we generate quasi-minimal degree-of-freedom formulations relating inlet conditions and heat release rate for both single-step and generalized multi-step chemical kinetic models.
Velocity measurement based on bolus tracking with the aid of three-dimensional reconstruction from digital subtraction angiography

The problem of blood flow measurement in x-ray angiography using measurements of the leading edge of the contrast bolus as it traverses the vascular bed is considered. A new technique for velocity measurement is presented based upon the ratio of the temporal derivative to the spatial derivative of the contrast bolus in the direction of flow. With the addition of a small correction factor, the value obtained is shown to reflect the transport velocity, or the velocity at which the contrast is transported down the vessel of interest. Most blood flow measurements based on bolus tracking techniques are actually using the contrast transport velocity to represent the blood flow velocity. Because of the streaming that occurs due to laminary flow conditions, the measured transport velocity is found to be somewhere between the average and the peak (central) fluid velocities for measurements taken during the traversal of the bolus leading edge. The spatial and temporal variation of the transport velocity are found to be consistent with the bolus motion expected in the presence of laminar flow. From x-ray images of contrast passage through simple tubes, we find that the derivative method measures the transport velocity during passage of the bolus leading edge. In most cases of laminar blood flow, the leading edge transport velocity can be 20%-40% higher than the average blood velocity.
The disruptive effects of explaining attitudes: The moderating effect of knowledge about the attitude object

Abstract Previous studies have found that asking people to explain the reasons for their attitudes can change these attitudes and lower attitude-behavior consistency. We found that people's knowledge about the attitude object moderates these effects. In a reanalysis of an earlier experiment, we found that analyzing reasons reduced the correlation between dating couples' attitudes toward each other and their break-up rates only for couples who had been dating for a relatively short period of time. In Study 1 analyzing reasons reduced the correlation between undergraduates' attitudes toward a political candidate and the number of fliers for that candidate they were willing to distribute only for those who were unknowledgeable about the candidate. In Study 2 analyzing reasons changed undergraduates' attitudes toward a set of political candidates only for those who were relatively unfamiliar with the candidates. Several possible reasons for the moderating effect of knowledge are discussed.
Attention: Reaction Time and Accuracy Reveal Different Mechanisms.

The authors propose that there are 2 different mechanisms whereby spatial cues capture attention. The voluntary mechanism is the strategic allocation of perceptual resources to the location most likely to contain the target. The involuntary mechanism is a reflexive orienting response that occurs even when the spatial cue does not indicate the probable target location. Voluntary attention enhances the perceptual representation of the stimulus in the cued location relative to other locations. Hence, voluntary attention affects performance in experiments designed around both accuracy and reaction time. Involuntary attention affects a decision as to which location should be responded to. Because involuntary attention does not change the perceptual representation, it affects performance in reaction time experiments but not accuracy experiments. The authors obtained this pattern of results in 4 different versions of the spatial cuing paradigm.
Inhibition of NF-AT-dependent transcription by NF-kappa B: implications for differential gene expression in T helper cell subsets

Abstract Activation of individual CD4+ T cells results in differential lymphokine expression: interleukin 2 (IL-2) is preferentially produced by T helper type 1 (TH1) cells, which are involved in cell-mediated immune responses, whereas IL-4 is synthesized by TH2 cells, which are essential for humoral immunity. The Ca(2+)-dependent factor NF-ATp plays a key role in the inducible transcription of both these lymphokine genes. However, while IL2 expression requires the contribution of Ca(2+)- and protein kinase C-dependent signals, we report that activation of human IL4 transcription through the Ca(2+)-dependent pathway is diminished by protein kinase C stimulation in Jurkat T cells. This phenomenon is due to mutually exclusive binding of NF-ATp and NF-kappa B to the P sequence, an element located 69 bp upstream of the IL4 transcription initiation site. Human IL4 promoter-mediated transcription is downregulated in Jurkat cells stimulated with the NF-kappa B-activating cytokine tumor necrosis factor alpha and suppressed in RelA-overexpressing cells. In contrast, protein kinase C stimulation or RelA overexpression does not affect the activity of a human IL4 promoter containing a mouse P sequence, which is a higher-affinity site for NF-ATp and a lower-affinity site for RelA. Thus, competition between two general transcriptional activators, RelA and NF-ATp, mediates the inhibitory effect of protein kinase C stimulation on IL4 expression and may contribute to differential gene expression in TH cells.
Potential thermal artifacts in hip joint wear simulators.

Frictional heat was monitored during wear tests of ultrahigh molecular weight polyethylene acetabular cups bearing against femoral balls of metal or ceramic in a hip simulator, using bovine serum as a lubricant. About 1 to 2 h of continuous cycling were required for the temperature in the zone of contact between the cup and ball to rise to its maximum steady value, and this equilibrium temperature was markedly higher with increased load and/or cycling rate. Frictional heating caused substantial precipitation of the proteins from the serum and, in some of the tests running at 1.5 or 2 Hz, an adherent proteinaceous layer was observed attached to the surface of the balls. The maximum temperature was also substantially higher in tests run with the cup mounted above the ball rather than below. Surprisingly, the tests running at higher frictional torque and temperature (i.e., those with the most protein precipitation and/or adherent layers) produced the least wear of the polyethylene. This might have been due to the solid proteins that formed a protective layer between the ball and cup. Because patients with hip prostheses typically do not walk for hours without rest, the maximum temperatures in vivo are likely to be much lower than those reached in the hip simulator. Therefore, the affects of protein precipitation on the resultant wear properties of the materials should be considered potential artifacts of the hip simulator tests. Increasing the volume of the lubricant bath reduced the maximum temperatures for tests running at 1.5 Hz but had little affect at 2 Hz. Reducing the cycling rate is an effective way to avoid overheating of the specimens, but this necessarily extends the time required to complete a test.
Helix–coil transition in nucleoprotein—theory and applications

A general theory of helix–coil transition of irreversibly complexed nucleoproteins is presented. The equations are tested by experimental results in basic polypeptide–DNA complexes, nucleohistone I and pea bud nucleohistones. They show good agreement between theory and experiments. The theory provides direct measurement of a fraction of DNA base pairs covered by proteins, yielding a value of about 75% histone-covered base pairs in pea bud nucleohistone. It also provides a measurement of an average number of amino acid residues per nucleotide in protein-bound regions. This number varies from 1.0 to 1.4 in DNA–polylysine or DNA–polyarginine and from 2.9 to 3.3 in nucleohistone Ia, Ib, f1, and pea bud nucleohistone.
Uncommon tumors and exceptional therapies: paradox or paradigm?

Why does it seem that, repeatedly, when a new treatment with a striking effect is discovered in the cancer field, it is effective for a very rare cancer type? For example, groundbreaking therapeutic discoveries have been made for extremely uncommon malignancies such as hairy cell leukemia, chronic myelogenous leukemia, seminoma, gastrointestinal stromal tumor, (del)5q myelodysplastic syndrome, and acute promyelocytic leukemia. In contrast, progress in the most common and most intensively studied tumors—lung, breast, prostate, and colon cancer—has been slow and incremental. We hypothesize that the reason for this phenomenon is that the pathophysiologic basis for a tumor being rare is one and the same as the reason that it may ultimately be so treatable. That is, if a cancer can be derived only via a single aberrant molecular genetic aberration, then it should be both rare and easily targeted by a molecular cancer therapeutic approach. If, on the other hand, many distinct pathways can lead to the development of a specific tumor type, it should occur much more commonly and be significantly more difficult to treat. The corollary to our hypothesis is the prediction that new therapies will continue to show their most salutary effects in rare cancers. Furthermore, only by stratifying the common tumors, especially when using targeted agents, into the molecular subsets of diseases that compose them are we likely to achieve a substantial effect in these disorders. [Mol Cancer Ther 2007;6(4):1175–9]
Body coupled communication: The channel and implantable sensors

To enable long-term medical monitoring, power consumption of the sensor nodes must be minimized. Most sensors power budgets are dominated by storing acquired data to memory or transmitting the information off the node. Body area networks (BAN) can decrease the power used by the sensor node and can be formed using body coupled communication (BCC). This paper will propose and verify an electrical model of the human body for BCC. This body model gives greater insight into how BCC works and how receiver architecture affects channel gain. Utilizing this insight the channel gain was increased by almost 20 dB. The proposed model allows for implants and explains how implants are able to transmit information outside the body using BCC. As it is important to have electrically isolated equipment to measure the BCC channel, a battery-powered wireless transmitter and receiver were created to measure the channel gain. The design of the measurement equipment is also detailed.
The accumulation of a platelet protein, thrombospondin, at the site of arterial thrombus formation: preliminary report.

There are many methods available for the detection of thrombosis, none of which are noninvasive, rapid and accurate. Thrombospondin is a platelet protein that is present in the developing thrombus and may be an effective substance to use for imaging thrombosis. Vascular ste nosis and thrombosis were produced in coronary, carotid and femoral arteries in eleven adult mongrel dogs.131I labeled thrombospondin was administered to each animal to determine whether the radiotracer accumulated at the site of thrombus formation. The radioactivity per gram of vessels with thrombi was significantly different from the control vessels or whole blood (p=0.0037 andp=0.0015, respectively, paired t-test). This preliminary work suggests that iodinated thrombospondin accumulates at the site of thrombus formation. Labeled thrombospondin may be a rapid, safe and accurate method of detecting arterial thrombosis.
Setting educational priorities for women's preventive health: measuring beliefs about screening across disease states.

Objective: To measure women's beliefs about disease screening in a consistent manner across disease states to identify priority areas for educational and motivational interventions. Methods: A cross-sectional, mailed survey of female patients, age ≥52, was conducted through a primary care practice-based research network. The Risk Behavior Diagnosis Scale, a validated 12-item instrument, was used to measure beliefs about disease severity, disease susceptibility, ability to obtain screening (self-efficacy), and response efficacy. These beliefs were measured for colon cancer, breast cancer, and osteoporosis. Results: One hundred twenty-eight surveys were returned from 425 women invited to participate (RR 30%). Significant differences in beliefs were noted across disease states for disease severity (F = 21.67, p < 0.001), disease susceptibility (F = 14.68, p < 0.001), self-efficacy (F = 42.85, p < 0.001), and response efficacy (F = 55.49, p < 0.001). Analysis by logistic regression indicated four beliefs to b...
Effects of Sweep and Nonplanarity on a Delta-Winged Biplane

A low-speed wind-tunnel investigation is presented, exploring the effect of delta wings configured in an 'X' biplane geometry. Wing leading-edge sweeps ranging from 50 to 70 deg and anhedrat/dihedrai angles up to 40 deg were explored. Results indicated a significant attenuation of vortex lift production, while the attached now lift component was enhanced due to nonplanarity, an outcome supported by theory developed to analytically simulate this wing geometry. Observed benefits of this wing configuration amplify with wing slenderness, where marked increases in the range parameter may be realized. Both theory and experiment indicate that the optimal anhedral/dihedral angles for the tested geometries ranged from 20 to 30 deg.
Definitive evidence for similarity in the active site of renin and acidic protease

Abstract The pressor enzyme renin from the mouse submaxillary gland was inactivated rapidly by diazoacetyl-D,L-norleucine methyl ester in the presence of cupric ion. The ion was essential to this reaction. The complete inactivation was obtained by the stoichiometric reaction of the reagent as indicated by the stoichiometric incorporation of norleucine into the renin molecule. The incorporated norleucine could be removed by treatment with 0.2 M hydroxylamine in 8 M urea indicating that a carboxyl group presumably essential for catalysis was esterified by the aliphatic diazo reagent. Renin from the hog kidney was also inactivated completely by a similar reaction. Since the requirement of cupric ion in the inactivation by aliphatic diazo compound is the most notable specific feature of acidic proteases, it is proposed that renin have a catalytic site similar to those of acidic proteases and that renin belongs to the family of acidic proteases, though its specificity determining site may be somewhat different.
Rhabdomyolysis in children: A 3-year retrospective study

The case reports of 4 pediatric patients illustrate the complex clinical scenarios in which childhood rhabdomyolysis/myoglobinuria occurs. Children ranged in age from 8-18 years. Presumed etiologies of rhabdomyolysis/myoglobinuria included Neisseria sepsis, exertion-related episodes, dialysis disequilibrium, and diabetic ketoacidosis. No child developed respiratory or renal failure. all children were discharged with normal muscle power, indicating the benign nature of this disease and the importance of aggressive management.
Arginine vasotocin delays extinction of a conditioned avoidance behavior in neonatal chicks.

Abstract One minute after single-trial avoidance conditioning, young cockerels received intracerebroventricular or intraperitoneal injections of saline or arginine vasotocin (dose range: 0.004 to 16 μg/chick). Retroactive enhancement of the learned response was observed 24 hours post-training for some dose levels, but not for others. A 0.4 μg vasotocin dose also delayed extinction when injected 9 minutes after training. Behavioral similarities between avian and mammalian responses to vasotocin and other neuroactive peptides are discussed.
Rapid removal of excessive iron with daily, high-dose intravenous chelation therapy

We investigated the value of high-dose intravenous iron chelation therapy with deferoxamine as an alternative to conventional subcutaneous therapy in eight patients receiving regular transfusions who had massive iron stores, including two with clinical heart disease. Six to twelve grams of deferoxamine was infused daily for 12 hours over 12 to 25 months through externalized central venous catheters or implanted reservoirs. Serum ferritin levels decreased by 56% to 99%. Liver iron concentrations, measured by magnetic susceptibility in two patients, were 1234 and 2438 μg/gm wet weight (22.1 and 43.6 μmol/gm wet weight) after treatment for 17 and 25 months, respectively. A patient with congestive heart failure and a patient with severe ventricular dysrhythmias no longer required cardiac medication after 12 to 24 months of chelation therapy. Three episodes of bacteremia and three episodes of cellulitis accounted for a catheter-related infection rate of 0.14 per 100 patient-days. The catheter removal rate was 0.20 per 100 patient-days. No patient experienced serious visual, auditory, or other toxicities. We conclude that in some patients receiveing regular erythrocyte transfusions, high-dose intravenous chelation therapy with deferoxamine is superior to conventional subcutaneous treatment.
Outcome states of colorectal cancer: identification and description using patient focus groups

Objective: Utilities for the outcome states of colorectal cancer must be measured to evaluate the cost-utility of screening and surveillance strategies for this disease. We sought to identify these outcome states, define their associated areas of morbidity, and construct representative descriptions of them for use in a utilities assessment instrument. Methods: We identified candidate colorectal cancer outcome states based on a review of the literature and interviews with health care professionals. We organized patient focus groups from each of the candidate outcome states to examine their homogeneity and define their associated areas of morbidity. After analyzing the focus group transcripts, we identified and described outcome states of colorectal cancer for future incorporation into a utilities assessment instrument. Results: Six candidate outcome states of colorectal cancer were identified based on disease stage and location at diagnosis. Thirty-eight patients then participated in six focus groups. Analysis of the focus group transcripts revealed seven areas of morbidity associated with colorectal cancer. These areas included problems with social interaction and cognition, fear of cancer recurrence, pain, fatigue, changes in bowel habits, and sexual dysfunction. Based on differences in the intensity and frequency of the symptoms reported in each of these areas, seven distinct outcome states of colorectal cancer were identified and described. Conclusion: Clinically distinct outcome states of colorectal cancer are determined by the stage and location of the cancer at the time of diagnosis. Descriptions of these outcome states were created using data collected from patient focus groups. These descriptions can be incorporated into a utilities assessment instrument.
Numerical performability evaluation of a group multicast protocol

Multicast protocols that provide message ordering and delivery guarantees are becoming increasingly important in distributed system design. However, despite the large number of such protocols, little analytical work has been done concerning their performance, especially in the presence of message loss. This paper illustrates a method for determining the performability of group multicast protocols using stochastic activity networks, a stochastic extension to Petri nets, and reduced base model construction. In particular, we study the performability of one such protocol, called Psync, under a wide variety of workload and message loss probabilities. The specific focus is on measuring two quantities, the stabilization time - that is, the time required for messages to arrive at all hosts - and channel utilization. The analysis shows that Psync works well when message transmissions are frequent, but it exhibits extremely long message stabilization times when transmissions are infrequent and message losses occur. We use this information to suggest a modification to Psync that greatly reduces stabilization time in this situation. The results provide useful insights into the behaviour of Psync, as well as serving as a guide for evaluating the performability of other group multicast protocols.
Growth and characteristics of type-II InAs/GaSb superlattice-based detectors

We report on growth and device performance of infrared photodetectors based on type II InAs/Ga(In)Sb strain layer superlattices (SLs) using the complementary barrier infrared detector (CBIRD) design. The unipolar barriers on either side of the absorber in the CBIRD design in combination with the type-II InAs/GaSb superlattice material system are expected to outperform traditional III-V LWIR imaging technologies and offer significant advantages over the conventional II-VI material based FPAs. The innovative design of CBIRDS, low defect density material growth, and robust fabrication processes have resulted in the development of high performance long wave infrared (LWIR) focal plane arrays at JPL.
Women's choices: an historical perspective of nursing as a career choice.

Abstract Over time there has been debate within nursing regarding its designation as a professional career or ‘skilled craftsperson” job. Although the respectability of nursing has always been acknowledged, for some nursing is not considered a high-status career. This qualitative study sought to identify the reasons why women chose to become nurses. Fifteen nurses who had graduated from nursing school between 1900 and 1985 were interviewed and asked about their reasons for choosing nursing as a career. Various themes emerged as consistent in their choice to enter nursing. Paramount was the desire to be of service. The other primary motivator was the need for a practical career that was viewed as satisfying, flexible, accessible in terms of cost of schooling, always in demand, and respectable. When nursing was chosen in the face of family opposition, it was viewed as a calling where one could be of service.
Light-Scattering Studies of Concentrated Copolymer Micellar Solutions

We report the analyses of an extensive set of light scattering intensity distributions from triblock copolymer micelles in aqueous solutions. We investigated two Pluronics, P84 (PEO19-PPO43-PEO19) and P104 (PEO27-PPO61-PEO27) in an entire range of the disordered micellar phase. Our previous small-angle neutron scattering (SANS) study showed that the micelle is spherical and consists of a compact hydrophobic core and a hydrophilic corona region. In that paper (Liu, Y. C., et al. Macromolecules 1998, 31, 2236−2244), we proposed a “cap-and-gown” model for the microstructure of the micelle, taking into consideration the polymer segmental distribution and water penetration profile in the core and corona regions. We took into account the intermicellar correlation using the adhesive hard-sphere model of Baxter. With this combined model, we obtained consistent trends for important parameters such as the aggregation number, hydration number per polymer in both the core and corona, and surface stickiness. The struc...
Control of ATP-dependent CO2 fixation in extracts of Hydrogenomonas facilis: NADH regulation of phosphoribulokinase.

Abstract The role of NADH in stimulating ATP-dependent CO 2 fixation has been examined in crude extracts of Hydrogenomonas facilis . It has been found that the stimulation cannot be attributed to reduction of the product, 3-phosphoglyceric acid, and consequent regeneration of substrate. Rather, NADH appears to specifically affect phosphoribulokinase, probably by causing an allosteric transition of this regulatory enzyme. The kinetics of the NADH effect on CO 2 fixation suggest cooperative binding of the effector. A similar cooperative response of the enzyme to ATP has been noted. It is suggested that the control of CO 2 fixation is mediated by allosteric regulation of phosphoribulokinase activity.
Ab Initio Studies of the Exocyclic Hydroxymethyl Rotational Surface in α-d-Glucopyranose

The potential energy surface for rotation of the exocyclic hydroxymethyl group of α-d-glucopyranose has been studied using ab initio quantum mechanical methods. Relevant stationary points, including for the first time rotational transition states, have been characterized by full geometry optimization using basis sets ranging in quality from 6-31G(d) to 6-311(2d,1p). Effects of dynamical electron correlation on both the geometric structures and the energy surface are also investigated using second-order Moller−Plesset perturbation theory (MP2) and density functional methods (BLYP). A total of six stationary points along the hydroxymethyl rotational surface, including three minima and three transition states, were identified. The effects of basis set augmentation and electron correlation on the relative energies are small; the relative energies for each stationary point vary by less than 5 kJ mol-1 for all levels of theory considered. Final energetic barriers to hydroxymethyl rotation ranged from 15 to 29 k...
Annexin II expressed by osteoblasts and endothelial cells regulates stem cell adhesion, homing, and engraftment following transplantation.

Differentiation of hematopoietic stem cells (HSCs) after birth is largely restricted to the bone marrow cavity, where HSCs are associated closely with osteoblasts (OBs). How OBs localize HSCs to the endosteal niche remains unclear. To explore adhesive interactions between HSCs and OBs, a cell blot analysis was used that revealed 2 major bands that corresponded to monomers and multimers of annexin II (Anxa2). Immunohistochemistry revealed that OBs and marrow endothelial cells express Anxa2 at high levels. Function-blocking studies confirmed that Anxa2 mediates HSC adhesion mainly via the N-terminal portion of the Anxa2 peptide. Adhesion of HSCs to OBs derived from Anxa2-deficient animals (Anxa2−/−) was significantly impaired compared with OBs obtained from wild-type animals (Anxa2+/+). Moreover, fewer HSCs were found in the marrow of Anxa2−/− versus Anxa2+/+ animals. Short-term lodging, engraftment, and survival of irradiated mice with whole marrow cells were substantially inhibited by N-terminal peptide fragments of Anxa2 or anti-Anxa2 antibodies. Similar findings were noted in long-term competitive repopulation studies. Collectively, these findings reveal that Anxa2 regulates HSC homing and binding to the bone marrow microenvironment and suggest that Anxa2 is crucial for determining the bone marrow niche of HSCs.
Behavioral Problems and Social Competence in Children with Epilepsy

The purpose of this investigation was to evaluate relationships between seizure type in general, degree of interictal limbic system dysfunction in particular, and social competence and behavioral pathology in children with temporal lobe (n=21), primary generalized (n=21), and focal nontemporal epilepsies (n=14). The three groups were closely matched on several variables and compared on the mean Aggression, Total Social Competence, and Total Behavior Problems scale scores derived from a standardized behavioral rating instrument (The Child Behavior Profile). On the Aggression scale , the focal nontemporal group scored significantly lower than the temporal lobe group but did not differ significantly from patients with primary generalized epilepsy. On the Total Behavior Problems and Total Social Competence scales, the three seizure groups did not differ significantly from one another. The results are discussed in terms of the psychologic risk for specific behavioral problems associated with epilepsies varying in their probability of interictal disruption of limbic system functioning.
Nonviral gene vector formation in monodispersed picolitre incubator for consistent gene delivery

A novel picolitre incubator based microfluidic system for consistent nonviral gene carrier formulation is presented. A cationic lipid-based carrier is the most attractive nonviral solution for delivering plasmid DNA, shRNA, or drugs for pharmaceutical research and RNAi applications. The size of the cationic lipid and DNA complex (CL-DNA), or the lipoplex, is one of the important variations for consistency of gene transfection. CL-DNA size, in turn, may be controlled by factors such as the cationic lipid and DNA mixing order, mixing rate, and mixture incubation time. The Picolitre Microfluidic Reactor and Incubator (PMRI) system described here is able to control these parameters in order to create homogeneous CL-DNA. Compared with conventional CL-DNA preparation techniques involving hand-shaking or vortexing, the PMRI system demonstrates a greater ability to constantly and uniformly mix cationic lipids and DNA simultaneously. After mixing in the picolitre droplet reactors, the cationic lipid and DNA is incubated within the picolitre incubator to form CL-DNA. The PMRI generates a narrower size distribution band, while also turning the sample loading, mixing and incubation steps into an integrated process enabling the consistent formation of CL-DNA. The coefficient of variation (CV) of transfection efficiency is 0.05 and 0.30 for PMRI-based and conventional methods, respectively. In addition, this paper demonstrates that the gene transfection efficiency of lipoplex created in the PMRI is more reproducible.
Anti-inflammatory effects of angiotensin receptor blockers in the brain and the periphery.

In addition to regulating blood pressure, Angiotensin II (Ang II) exerts powerful pro-inflammatory effects in hypertension through stimulation of its AT1 receptors, most clearly demonstrated in peripheral arteries and in the cerebral vasculature. Administration of Ang II receptor blockers (ARBs) decreases hypertension-related vascular inflammation in peripheral organs. In rodent models of genetic hypertension, ARBs reverse the inflammation in the cerebral microcirculation. We hypothesized that ARBs could be effective in inflammatory conditions beyond hypertension. Our more recent studies, summarized here, indicate that this is indeed the case. We used the model of systemic administration of the bacterial endotoxin lipopolysaccharide (LPS). LPS produces a robust initial inflammatory reaction, the innate immune response, in peripheral organs and in the brain. Pretreatment with the ARB candesartan significantly diminishes the response to LPS, including reduction of pro-inflammatory cytokine release to the general circulation and decreased production and release of the pro-inflammatory adrenal hormone aldosterone. In addition, the ARB very significantly decreased the LPS-induced gene expression of pro-inflammatory cytokines and microglia activation in the brain. Our results demonstrate that AT1 receptor activity is essential for the unrestricted development of full-scale innate immune response in the periphery and in the brain. ARBs, due to their immune response-limiting properties, may be considered as therapeutically useful in a number of inflammatory diseases of the peripheral organs and the brain.
A letter from America: rescuing inpatient psychiatry.

In recent decades, American insurance companies have severely restricted medical reimbursement and access to treatment. Within this general trend, they have discriminated against psychiatry more than most other specialties, and have slashed in particular the most expensive facet of psychiatric care: inpatient treatment.1 The mean length of psychiatric stay in American hospitals has fallen from months to a handful of days. Realistically, how effectively can clinicians treat severely ill psychiatric patients in a three or four day hospital stay? Meanwhile, reimbursement for inpatient care has fallen so low (in some cases to 39% less than actual costs) that American hospitals have begun reducing psychiatric beds as well as lengths of stay.2 Patients in managed care plans are less likely to receive inpatient care than patients in fee-for-service plans.3 This drastic change in inpatient psychiatric care has had little to do with its clinical effectiveness and much to do with the managed care mantra of cost cutting. The promise that increased reimbursement for less costly day hospitals and outpatient services would compensate for this …