cssi/SciSciGPT-SciSciNet huggingface dataset:
Linking silver carp habitat selection to flow and phytoplankton in the Mississippi River

Invasive silver carp (Hypothalmichthys molitrix) occurs throughout much of the Mississippi River and threatens the Laurentian Great Lakes. To quantify habitat selection relative to river flow and potential phytoplankton food, 77 adult silver carp were implanted with ultrasonic transmitters during spring 2008 through spring 2009 in adjacent upstream dammed and downstream undammed reaches (48 km total) of the Mississippi River. Sixty-seven percent of the fish were located. Selection of major river habitat features (dammed vs. undammed, backwaters, channel border, wing dikes, island side channels, and the main channel) was quantified. Flow rates and chlorophyll a concentration were compared between silver carp locations and random sites. Foregut chlorophyll a concentrations plus presence of macrozooplankton and detritus of 240 non-tagged silver carp were quantified. About 30% of silver carp moved upstream into the dammed reach, where average flow was slower and chlorophyll a concentration was higher. Silver carp selected wing dike areas of moderate flow (about 0.3 m/s) and elevated chlorophyll a (about 7 μg/L) relative to random sites. No silver carp occurred in areas where flow was absent. Wing dikes were preferred while the main channel was avoided. Chlorophyll a concentrations in guts were positively related to temperature and were unrelated to flow or river chlorophyll a concentration. Macrozooplankton and detritus were rare in guts. Silver carp seek areas of low flow and successfully forage across a range of temperatures, flows, and chlorophyll a concentrations that occur in rivers and large lakes.
Carnitine palmitoyl-transferase enzyme inhibition protects proximal tubules during hypoxia

Carnitine palmitoyl-transferase enzyme inhibition protects proximal tubules during hypoxia. The role of inhibition of the CPT enzymes responsible for accumulation of long chain acylcarnitines (LCAC) during hypoxia in the proximal tubule has not been previously examined. We have characterized CPT enzyme activities in mitochondrial fractions of rabbit proximal tubules. Malonyl CoA-sensitive CPT I activity (1.1 ± 0.3 nmol/min/mg protein), and detergent-solubilized, malonyl CoA-insensitive CPT II activity (2.3 ± 0.4 nmol/min/mg protein) were readily detected in proximal tubule mitochondrial fractions. Subjecting rabbit proximal tubules to various periods of hypoxia did not significantly change mitochondrial CPT I or CPT II activities. Thirty minutes of hypoxia resulted in an increase in lysophospholipid mass from 440 ± 105 to 720 ± 93 pmol/mg protein, N = 5, LCAC mass from 79 ± 11 to 618 ± 34 pmol/mg protein, N = 5, and lactate dehydrogenase (LDH) release from 9 ± 1% to 46 ± 3%, N = 8. Pretreatment of proximal tubules with two different CPT inhibitors, glybenclamide (Glyb) 400 µ M and oxfenicine (Oxfe) 1mM, resulted in reduction in the magnitude of hypoxia-induced lysophospholipid formation 490 ± 160 (Glyb), 342 ± 150 pmol/mg protein (Oxfe), N = 4, hypoxia-induced LCAC formation 295 ± 27 (Glyb), 128 ± 16 pmol/mg protein (Oxfe), N = 5, and LDH release 25 ± 1% (Glyb) and 19 ± 2% (Oxfe), N = 8. The protective effect of CPT inhibition was also associated with increased production of lactate suggesting the modulation of a substrate-mediated metabolic switch. Immunoblots demonstrated that hypoxia caused a time dependent hydrolysis of fodrin-alpha subunit and that CPT inhibition protected against hypoxia-induced fodrin proteolysis. These data suggest a unifying hypothesis that links phospholipase A 2 (PLA 2 ) activation, and hypoxia-mediated fodrin proteolysis to the proximal tubule mitochondrial CPT system. I propose that CPT inhibition may represent a novel mechanism to ameliorate proximal tubule cell death during hypoxia.
Vacuum-assisted closure: a new method for treating patients with giant omphalocele

Introduction: Closure of giant omphalocele can present a surgical challenge. Neither silo, skin flap, nor primary closure has been successful in treating all patients. We present a novel application of the vacuum-assisted closure (VAC) device, which allows for improved results in these difficult cases. Methods: The VAC device (KCI, San Antonio, Tex) consisted of a sponge applied directly to the bowel and liver, covered with impermeable transparent dressing, and attached to a low negative pressure system. The sponge was changed every 3 to 5 days under local sedation. Patients: All 3 patients had giant omphaloceles. The first infant, a 34 week gestational age (WGA) male, was initially treated with silo reduction, which disrupted after 21 days. The large mass of bowel and liver made primary closure impossible. The VAC was applied for 45 days. The viscera was easily reduced and subsequently covered with acellular dermal matrix (AlloDerm). The VAC was reapplied, and the small remaining defect was skin-grafted. The second male infant was a 34 WGA male infant who became septic after failure of prosthetic mesh closure. The VAC was applied for 22 days after removal of the mesh. The infection resolved, and the defect size was reduced, allowing for skin flap closure. Mesh infection and development of an enterocutaneous fistula in the last patient, a 37 WGA female child, were treated by mesh removal and application of the VAC for 36 days. The VAC allowed for control of the fistula output and development of a healthy granulation bed. Results: Vacuum-assisted closure was associated with (1) rapid shrinkage and reduction of the viscera (22-45 days); (2) cleansing of the wound; (3) excellent granulation; (4) maintenance of a sterile environment; and (5) ease of use, with changes possible at the bedside. Conclusion: The VAC device should be considered a safe and effective alternative in treating complicated cases of giant omphalocele until a more definitive closure method can be used.
Diagnostic Tools for Multivariable Model-Based Control Systems

In this paper we propose a set of diagnostic tools that can be used for detecting and estimating the causes for performance degradation in multivariable model-based control systems. Two simple diagnostic tests are proposed, on the basis of prediction error analysis, to detect the performance degradation and bifurcate the potential causes for the degradation. These tests are useful for narrowing down the list of potential causes for performance degradation. For detailed fault estimation, we propose to use a stochastic model based on Gaussian-sum statistics. The optimal estimation for this model requires a bank of a growing number of filters and is computationally intractable. To propose a practical solution, we combine the different suboptimal approaches in the literature. The results of the diagnosis can be used for alerting the operators about the potential faults and for adapting the controllers.
Intensity non-standardness affects computer recognition of anatomical structures

Since MR image intensities do not possess a tissue specific numeric meaning, even in images acquired for the same subject, on the same scanner, for the same body region, by using the same pulse sequence, it is important to transform the image scale into a standard intensity scale so that, for the same body region, intensities are similar. The lack of a standard image intensity scale in MRI leads to many difficulties in tissue characterizability, image display, and analysis, including image segmentation and registration. The influence of standardization on these tasks has been documented well; however, how intensity non-standardness may affect the automatic recognition of anatomical structures for image segmentation has not been studied. Motivated from the study that we previously presented in SPIE Medical Imaging Conference 2010,1, 2 in this study, we analyze the effects of intensity standardization on anatomical object recognition. A set of 31 scenarios of multiple objects from the ankle complex included in the model, plus seven different realistic levels of non-standardness introduced are considered for evaluation. The experimental results imply that, intensity variation among scenes in an ensemble - a particular characteristic of the behavior of non-standardness - degrades object recognition performance.
Fast turn-on characteristics of tungsten-based dispenser cathodes. II

Abstract In the Proceedings of the 1982 Tri-Service Cathode Workshop, the authors described studies of the reactivations of tungsten-based dispenser cathodes following poisonings of the kind expected during shelf storage of a microwave tube [Appl. Surface Sci. 16 (1983) 73]. Further work on the problems of reactivation following such poisoning is described here. In addition to coated (“M”) and uncoated tungsten matrix cathodes, the tungsten-iridium mixed metal matrix (“MM”) cathode has been studied. In general reproducible results have been obtained from different examples of the same type of “M” and uncoated cathodes. However, although some “MM” cathodes have exhibited good reactivation characteristics, a large variation has been observed between different examples of “MM” cathodes. The composition of the impregnant in the dispenser cathodes has been found to be an important factor in determining the reactivation rate of a cathode. As the barium oxide concentration in the impregnant increases, the cathode will recover faster from a poisoning exposure. Studies of the poisoning caused by combinations of different gases suggest that poisoning will occur if there is a sufficient exposure of a poisoning agent, regardless of the total exposure. The exposures necessary to poison a cathode are so small, that poisoning of the cathode appears probable during shelf storage of a microwave tube. The reactivation results have been summarised in terms of the times and temperatures required to achieve both a given current density and a given degree of reactivation from a poisoned cathode. The studies also indicate that the limiting step during the reactivation process involves the dispensing of fresh material to the cathode surface rather than the desorption or conversion of a poisoned surface layer.
Identification of Ionizing Sources and Young Stellar Objects in M17

We have obtained high-quality 2 μm (K-band) spectra of 25 stars in the direction of the heavily extincted, Galactic star-forming region M17. Interloping cool field giants are a potential source of confusion, but K-band spectra combined with normal JHK colors can identify and distinguish these stars via their strong CO absorption features at λ ≥ 2.29 μm. Among the other sources, we have identified five stars as O type from their spectral lines of H I, He I, He II, and N III by using a K-band classification system that we have developed. These provide the number of Lyman-continuum photons required by radio continuum observations. The remaining stellar objects, all but one with strong near-infrared (NIR) excesses, show completely different spectral characteristics from known main-sequence stars. Three are completely featureless throughout the K band, four (possibly five) show CO bands in emission, and two (candidate FU Orionis-like objects) have CO bands in absorption combined with extreme NIR excesses. We suggest that these stellar objects are relatively massive young stellar objects, still shrouded by circumstellar material.
L-leucine, a specific inhibitor of a rare human placental alkaline phosphatase phenotype.

FISHMAN et al. reported that human placental alkaline phosphatase (Regan isoenzyme) was found in the serum and tumour tissue of a patient with lung cancer1. Two electrophoretically different variant forms of Regan alkaline phosphatase with a greater sensitivity to inhibition by L-leucine have since been described: the ‘Nagao isoenzyme’2, and a hepatoma-specific alkaline phosphatase3–5. Inglis et al.6 reported that the L-leucine-sensitive Nagao isoenzyme found in some cancer patients closely resembled the ‘D variant’ of human placental alkaline phosphatase, a rare phenotype defined electrophoretically on starch gel which is found in less than 1% of the general population of pregnancies7. An example was reported of a pregnancy serum D-phenotype enzyme presumably of placental origin, confirmed by electrophoresis established as L-leucine-sensitive6. Most interesting was the occurrence of the variant at high frequency in the ovarian cancer patients surveyed6,8. To extend the observations of Inglis et aL, screening for the phosphatases in placentae was carried out, both to establish the frequency of the L-leucine-sensitive placental phenotypes (which should match the frequency of the electrophoretically defined D variant phenotypes) and to provide enough enzyme to enable purification and characterisation. Supply of cancer tissue is generally restrictive for this purpose.
Research Article: A scaled-down and simplified protocol for purifying recombinant Taq DNA polymerase

Abstract. We previously described in a paper published in BIOS an undergraduate lab activity involving the gene cloning, expression, and purification of Thermus aquaticus (Taq) DNA polymerase, an enzyme used in the polymerase chain reaction (PCR). Based on the large number of requests for biological materials and questions about the protocols this paper invoked, we explored methods to simplify the protein purification portion of the published lab activity. A faster and simpler protocol would permit labs and classes with limited equipment or supplies the ability to produce active Taq DNA polymerase more easily for both teaching and research use. In the simplified protocol described here, bacterial cell lysis and enzyme purification is achieved in a small starting volume using only a hot water bath, a microcentrifuge, and one simple buffer. The purified enzyme from this protocol works well in PCR, and we additionally describe its use in a 2X master mix.
Scientists assess impact of Indonesia fires

The fires burning in Indonesia over the past several months are setting aflame the biomass and wildlife habitat of the tropical forests, spreading a dangerously unhealthy haze across the populous country and nearby nations in southeast Asia, causing transportation hazards, and sending plumes of smoke up into the troposphere. Most of the fires have been set—by big landowners, commercial loggers, and small farmers—in attempts to clear and cultivate the land, as people have done in the past. But this year a drought induced by El Nino limited the rainfall that could help extinguish the flames and wash away the smoke and haze. In addition, some scientists say that smoke could even delay the monsoon, which usually arrives in early November.
The preparation and some reactions of triphenylsilylsodium and methyldiphenylsilylsodium

Abstract Triphenylsilylsodium and methyldiphenylsilylsodium have been prepared in THF in 70–80% yields by reaction between the corresponding disilanes and sodium in the presence of small amounts of naphthalene or biphenyl, or between the corresponding disilanes or chlorosilanes and sodium in the presence of naphthalene. No silylsodium compounds were formed by the reaction of the chlorosilanes with sodium in the presence of biphenyl. Attempts to prepare dimethylphenylsilylsodium from 1,1,2,2-tetramethyl-1,2-diphenyldisilane and sodium in the presence of naphthalene or biphenyl failed. In these cases dimethylphenylsilyl-substituted derivatives of the hydrocarbons were isolated. Triphenylsilylsodium and methyldiphenylsilylsodium are approximately as stable as the established silyllithium compounds. In reactions with halogen-containing compounds the silylsodium compounds gave higher yields coupled products than the comparable silyllithium compounds.
Does US Medical Licensing Examination Step l Score Really Matter in Surgical Residency Match Outcomes (and Should It)

Background The relationship between US Medical Licensing Examination Step 1 scores and core surgical-specialty match outcomes has not been well defined. Study Design With IRB approval, we measured associations between aggregate Step 1 scores and other specialty-specific, match-process variables for 3 surgical-specialty matches. Chi-square tests measured differences between proportions of US students and independent applicants (ie, all non-US allopathic student applicants) who matched. Independent samples t-tests compared differences in Step 1 scores between matched- and unmatched-applicant groups. Pearson correlations measured the magnitude and direction of associations between matched-applicants' Step 1 scores and other variables of interest and between Step 1 scores for all match participants and percentage of positions filled by US students (two-tailed p values). Results Step 1 scores were lower for unmatched- than matched-applicant groups for each specialty examined (each p Conclusions Step 1 scores were closely related to match process outcomes and match participation itself, with increasing Step 1 scores among both matched- and unmatched-applicant groups as specialty selectivity increased.
Self-doped conducting copolymers: a charge and mass transport study of poly{pyrrole-CO[3-(pyrrol-1-YL)propanesulfonate]}

Abstract A self-doped copolymer of pyrrole, poly{pyrrole-co-[3-(pyrrol-1-yl)propanesulfonate]}, in which the charge compensating counterion is bound covalently to the polymer main chain, has been prepared and the charge and mass transport in the polymer during redox switching has been investigated using chronocoulometry and microgravimetry as a function of the supporting electrolyte The results are compared with the behavior of polypyrrole under similar conditions It is shown that within this new family of materials, called “self-doped conductive polymers”, ion mobility is restricted to cationic species and thus the polymer can be viewed as an ion-specific membrane This is in contrast to the case of polypyrrole, where a more complex behavior prevails The charge passed during the chronocoulometric experiment varies as tα where 0.2
Live free or die: an immature T cell decision encoded in distinct Bcl-2 sensitive and insensitive Ca2+ signals

In the developing thymus, strong T cell receptor (TCR) activation by self-antigens induces negative selection and weak TCR activation induces positive selection. Both processes are mediated by Ca(2+) signals, raising the question of how a single second messenger like Ca(2+) can mediate such diverse cell fates. Recent findings indicate that graded TCR activation signals are encoded in distinct patterns of Ca(2+) elevation. The anti-apoptotic protein Bcl-2 discriminates between these Ca(2+) signaling patterns, selectively inhibiting pro-apoptotic Ca(2+) signals induced by strong TCR activation without suppressing pro-survival Ca(2+) signals induced by weak TCR activation.
Androgen ablation mitigates tolerance to a prostate/prostate cancer-restricted antigen

To understand the T cell response to prostate cancer, we created transgenic mice that express a model antigen in a prostate-restricted pattern and crossed these animals to TRAMP mice that develop spontaneous prostate cancer. Adoptive transfer of prostate-specific CD4 T cells shows that, in the absence of prostate cancer, the prostate gland is mostly ignored. Tumorigenesis allows T cell recognition of the prostate gland—but this recognition is tolerogenic, resulting in abortive proliferation and ultimately in hyporesponsiveness at the systemic level. Androgen ablation (the most common treatment for metastatic prostate cancer) was able to mitigate this tolerance—allowing prostate-specific T cells to expand and develop effector function after vaccination. These results suggest that immunotherapy for prostate cancer may be most efficacious when administered after androgen ablation.
Current Anti–Vascular Endothelial Growth Factor Dosing Regimens: Benefits and Burden

Topic To examine the outcomes of clinical trials and case studies that investigated the different dosing regimens used for the 3 intravitreal anti–vascular endothelial growth factor (VEGF) inhibitors that are available currently. The Comparisons of Age-Related Macular Degeneration (AMD) Treatments Trial (CATT) data are discussed briefly here and are reviewed in greater detail in a separate accompanying article. Clinical Relevance Sustained improvement with the 2 most widely used anti-VEGF drugs, bevacizumab and ranibizumab, requires monthly visits, posing a difficulty for patients. Thus, there is a need to evaluate whether individualized treatment regimens may reduce patient burden and improve patient outcomes. Methods Review of clinical trials and case studies presented at recent medical conferences and published in peer-reviewed literature. Results Numerous trials, including the Efficacy and Safety of Ranibizumab in Patients with Subfoveal Choroidal Neovascularization (CNV) Secondary to AMD, Prospective Optical Coherence Tomography Imaging of Patients with Neovascular AMD Treated with Intraocular Ranibizumab, Study of Ranibizumab in Patients with Subfoveal CNV Secondary to AMD, Extension Study to Evaluate the Safety and Tolerability of Ranibizumab in Subjects with CNV Secondary to AMD or Macular Edema Secondary to Retinal Vein Occlusion, Safety Assessment of Intravitreal Lucentis for AMD, and CATT, have evaluated alternatives to monthly dosing. Evidence suggests that either a treat-as-needed or, possibly, a treat-and-extend regimen provides a reasonable approach to monthly injections recommended for bevacizumab and ranibizumab, with the caveat that as yet, careful and ongoing surveillance remains a key feature of optical management. Conclusions Individualization of antiangiogenic treatment using data from clinical trials evaluating various dosing regimens against the patient's disease, lifestyle, and economic restrictions continues to evolve. Financial Disclosure(s) Proprietary or commercial disclosure may be found after the references.
BARIUM ENEMA: IS IT IMPORTANT IN THE EVALUATION OF CHILDHOOD CONSTIPATION

We question the importance of barium enema (BE) in the evaluation of childhood constipation. The radiographic appearance of a transition zone (TZ) or delayed evacuation of barium (DEB) on BE necessitates a second procedure, rectal suction biopsy (RSB). RSB is performed to confirm the presence of submucosal ganglion cells and rule out Hirschsprung's disease (HD). To determine if RSB alone is sufficient to evaluate the child with constipation, we retrospectively reviewed the charts of 76 children (1day-18yrs) with constipation who had BE & RSB. BE were reviewed for TZ, DEB and/or other colonic anatomic abnormalities (CAA). Seven children (9%) had CAA; 5 neonates (under 1 wk of age) with microcolon and 2 infants with previous history of NEC had colonic strictures. TZ was present in 23 patients (30%) and DEB in 26 patients (34%). Results of RSB are presented below: DEB is an unreliable radiographic sign for the diagnosis of HD; 77% of these children had normal RSB. In addition, the presence of a TZ is nondiagnostic of HD. Eleven (48%) children with suspected TZ had ganglion cells present on RSB. Three children with normal BE had no ganglion cells on RSB. A normal BE does not rule out HD. Therefore, infants over 7 days of age who have constipation and no previous NEC history or signs of intestinal obstruction can be adequately screened for HD by RSB without BE.
THE PHYSIOLOGICAL FRACTIONATION OF PITUITARY GONADOTROPIC FACTORS CORRELATED WITH CYTOLOGICAL CHANGES1

Removal of estrogen or androgen influence by gonadectomy and the controlled administration of gonadal steroids resulted in regulation of the concentration of follicle stimulating (FSH) and lutcinizing (LH) factors in pituitary glands of young adult rats. These physiological changes were correlated with cytological findings. Gonadectomy in both sexes results in a marked increase in both LH and FSH in the pituitary as well as a corresponding increase in the red and purple (PAS-Methyl blue staining) pituitary gonadotropes. The administration of the equivalent of 3 μg. of estradiol benzoate per day over a 45-day period stimulates depletion of LH. FSH is also markedly decreased. The cytological picture shows very few red but some purple gonadotropes. On the other hand, the administration of the equivalent of 3 mg. of testosterone propionate per day over a 45-day period also depletes the LH but the FSH content remains high and the correlated cytological findings show a corresponding decrease in the red gonadotr...
Structural and cytochemical characterization of three specialized peroxisome types in soybean

Structural and cytochemical comparisons were made between three peroxisome types in soybean [Glycine max (L.) Merr. cv. Centennial]. Leaf peroxisomes were densely granular organelles with an amorphous nucleoid and were generally located in close proximity to the chloroplasts. Catalase (EC 1.11.1.6) and glycolate oxidase (EC 1.1.3.1) were localized in these peroxisomes although glycolate oxidase was absent from the nucleoid region. Glyoxysomes, present in the etiolated cotyledons, were coarsely granular organelles that were generally in close proximity to lipid bodies. Malate synthase (EC 4.1.3.2), catalase, and glycolate oxidase were present throughout the matrix. Although peroxisomes were found in both infected and uninfected nodule tissue, uninfected interstitial cell peroxisomes were the most developed. These organelles contained a core surrounded by a less electron-opaque periphery that frequently was in close association with (but distinct from) a network of smooth endoplasmic reticulum. Of the enzymes studied, only catalase and urate oxidase (EC 1.7.3.3) were detected in the nodule peroxisomes. Neither enzyme was detected in the peripheral area of the peroxisome. These data indicate that peroxisomes in the three tissue types have organelle associations, internal structures, enzyme constitutions and packaging that reflect their metabolic differences.
Intracoronary artery thrombus formation in unstable angina: A clinical, biochemical and angiographic correlation

Objectives. We examined the relation between the level of urinary fibrinopeptide A and the presence of angiographic intracoronary thrombus in patients with unstable angina to determine whether this marker predicts active thrombus formation. Background. Although it is known that thrombus plays a role in acute ischemic syndromes, a noninvasive method to predict its presence in individual patients with unstable angina has not been determined. Fibrinopeptide A is a polypeptide cleaved from fibrinogen by thrombin and thus is a sensitive marker of thrombin activity and fibrin generation. Methods. Angiographic thrombus, graded 0 to 4, and the presence of ST segment depression or T wave inversions, or both, on the electrocardiogram (ECG) were related to fibrinopeptide A levels in 24 patients with rest angina of new onset, 18 with crescendo angina, 19 with stable angina and 9 with chest pain but without coronary artery disease. All patients had chest pain within the 24 h of sample acquisition. Results. The angiographic incidence of thrombus was significantly higher in patients with new onset of rest angina (67%, p < 0.001) and crescendo angina (50%, p < 0.001) as were fibrinopeptide A levels (p = 0.002). Fibrinopeptide A levels correlated significantly (p < 0.001) with the presence of a filling defect (grade 4 intracoronary thrombus) or contrast staining (grade 3). All patients with fibrinopeptide A ≥8 ng/mg creatinine showed grade 3 to 4 thrombus and 15 of 16 patients with levels ≥6.0 ng/mg creatinine exhibited angiographic evidence of thrombus (13 with grades 3 to 4). Patients with reversible ST changes on the ECG had significantly higher levels of fibrinopeptide A (p < 0.001), and ST changes correlated significantly with the presence of angiographic thrombus (p < 0.001). Nonetheless, a significant minority of patients with unstable angina had neither angiographic nor biochemical evidence of thrombus. Conclusions. Elevated fibrinopeptide A levels in unstable angina reflected active intracoronary thrombus formation and were present in patients with angina of new onset as well as crescendo angina. Reversible ST changes are accompanied by thrombin activity and angiographic thrombus formation. However, a sizable percentage of patients with unstable angina had no evidence of thrombus and these patients may have had translent platelet aggregation without fibrin thrombus formation.
The ingrowth of new bone tissue and initial mechanical properties of a degrading polymeric composite scaffold.

Trabecular bone deficiency causes a dilemma at surgery in a variety of clinical situations, including trauma, tumor resection, and reconstruction. A synthetic material to replace trabecular bone wo...
Effect of somatostatin on parathyroid hormone and calcitonin secretion.

This study evaluated the effect of somatostatin on immunoreactive parathyroid hormone (iPTH) and calcitonin (iCT) secretion in vivo in rats and monkeys and on iPTH secretion in vitro by normal bovine parathyroid tissue and by a human parathyroid adenoma. Somatostatin infusion promptly (within 0.5 h) suppressed both iPTH and iCT in both species studied in vivo, the suppression being progressive during the infusion period. In in vitro studies, somatostatin caused significant dose-related decreases in basal, low Ca-stimulated, and high Ca-suppressed PTH secretion from normal bovine parathyroid tissue and from basal and low Ca-stimulated PTH secretion from a human parathyroid adenoma. Therefore, somatostatin 1) suppresses both PTH and CT secretion in vivo; 2) acts directly on the parathyroid cell and presumably directly on the C-cell also; 3) acts upon normal and adenomatous parathyroid tissue; 4) suppresses basal, low Ca-stimulated and high Ca-suppressed PTH secretion; and 5) has a dose-related effect. The p...
Reexamination of Possible Bimodality of GALLEX Solar-Neutrino Data

The histogram formed from published capture-rate measurements for the GALLEX solar-neutrino experiment is bimodal, showing two distinct peaks. However, the histogram formed from published measurements derived from the similar Gallium Neutrino Observatory (GNO) experiment is unimodal, showing only one peak. Nevertheless, the two experiments differ in run durations: GALLEX runs are either three weeks or four weeks (approximately) in duration, whereas GNO runs are all about four weeks in duration. When we form three-week and four-week subsets of the GALLEX data, we find that the relevant histograms are unimodal. The upper peak arises mainly from the three-week runs, and the lower peak from the four-week runs. The four-week subset of the GALLEX dataset is found to be similar to the GNO dataset. A recent re-analysis of GALLEX data leads to a unimodal histogram.
Simulated foreign policy exchanges: The rationale underlying a theory of foreign policy interaction

This article is the first of a two‐part series on the development of a theoretical perspective for explaining foreign policy exchanges between nations. The first paper discusses the substantive thrust of the research, and presents an overview of the Monte Carlo computer simulation which lies at its core. The theory largely built on the body of research on events data analysis, attempts to assimilate the set of findings arising from this research into a single integrated theory. Basic assumptions of the theory derived from cybernetics and information theory are outlined, and the simulation rules used in the research are presented. These provide the basis for a later paper (to appear in Vol. 2, No. 2, 1975) that presents a formal mathematical theory which seeks to explain foreign policy exchanges.
Design considerations in scaled SONOS nonvolatile memory devices

Abstract Scaling the programming voltage, while still maintaining 10-year data retention time, has always been a big challenge for polysilicon–oxide–nitride–oxide–silicon (SONOS) researchers. We describe progress in the design and scaling of SONOS nonvolatile memory devices. We have realized −9+10 V (1 ms) programmable SONOS devices ensuring 10-year retention time after 107 erase/write cycles at 85°C. Deuterium anneals, applied in SONOS device fabrication for the first time, improves the endurance characteristics when compared with traditional hydrogen or forming gas anneals. We introduce scaling considerations and process optimization along with experiments and SONOS device characterization. A field programmable gate array-based measurement system is described for the dynamic characterization of SONOS nonvolatile memory devices.
Identification of Catechol-Protein Conjugates in Neostriatal Slices Incubated with [3H]Dopamine: Impact of Ascorbic Acid and Glutathione

There is evidence to suggest that degeneration of dopaminergic neurons in Parkinson's disease and certain other conditions results from the action of reactive species generated during the oxidation of dopamine. We, therefore, have begun to explore the conditions under which such reactive species are formed. Tissue slices prepared from rat neostriatum were incubated in a standard Krebs bicarbonate buffer for up to 120 min. In the presence of [3H]dopamine (0.01-100 microM), binding of tritium to the acid-insoluble protein fraction was detected. Binding was attenuated by the addition of ascorbate (0.085-0.85 mM) or glutathione (0.01-1.0 mM) to the buffer. Acid hydrolysis of the protein revealed the presence of cysteinyl-dopamine and cysteinyl-dihydroxyphenylacetic acid residues. These results suggest that dopamine oxidizes to form reactive metabolites, presumably quinones, that then bind to nucleophilic sulfhydryl groups on protein cysteinyl residues. The findings further suggest that the extent to which reactive metabolites are formed is determined in part by the balance between the availability of dopamine and the antioxidant environment.
Ocean temperature estimates from models and observations with application to OTEC

Large-scale estimates of ocean temperature, particularly at depth, are sparse. Accurate estimates of ocean thermal gradients are however important for proper and efficient placement of ocean thermal energy conversion (OTEC) plants. This study provides estimates from two data sets based on direct observation: the autonomous Argo profiling floats and the World Ocean Database (WOD), as well as from two large-scale, high resolution ocean models. These calculations can be used in geographic information system (GIS) models as a parameter for proper location of OTEC facilities.
Introduction of Impermeant Molecules into Synaptosomes Using Freeze/Thaw Permeabilization

Brief freezing as a means of transiently permeabilizing synaptosomes was explored. Rat brain synaptosomes frozen and thawed in the presence of 5% dimethyl sulfoxide, a cryoprotectant, were shown to release, in a calcium-dependent manner, previously accumulated [3H]norepinephrine and [14C]acetylcholine in response to elevated [K+]. In addition, synaptosomes subjected to freeze/thaw were shown to retain their ability to exhibit resting protein phosphorylation, as well as stimulated protein phosphorylation occurring in response to calcium influx. Brief freezing of synaptosomes in the presence of [gamma-32P]ATP and either the catalytic subunit of cyclic AMP-dependent protein kinase or calcium/calmodulin-dependent protein kinase II rendered the synaptosomal interior accessible to these agents, as reflected by the phosphorylation of substrate proteins, such as synapsin I, which reside within the nerve terminal. Inclusion of inhibitors of these protein kinases during freeze/thaw blocked synaptosomal protein phosphorylation, indicating that the inhibitors were also introduced. After freezing, the synaptosomes resealed rapidly and spontaneously, as shown by the inability of any of the agents to elicit an effect on phosphorylation when added at the end of the freezing period. The permeabilization procedure should contribute to an understanding of the functional roles of phosphoproteins, and of their associated protein kinases and protein phosphatases, in nerve terminals.
Effects of L-isopropylnorepinephrine, 3-isobutyl-1-methyl xanthine and dibutyryl cyclic AMP on hexose uptake and metabolism by rat striatal slices.

— Rat striatal slices in vitro undergo a number of changes in the pattern of their carbohydrate metabolism when incubated with either dibutyryl cyclic AMP or with the beta-adrenergic agonist l-isopropylnorepinephrine (IPNE) plus the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX). We have, in previous reports, shown that the content of glycogen in the slices is reduced by approx 50% upon incubation with these agonists. We now report that the rate of hexose uptake as measured by 3H uptake from a medium containing 1 mm-glucose with a trace of [3H]2-deoxyglucose (2-DOG) is reduced by 20–25% compared to basal uptake rates. The rate of lactic acid production by the slices is approximately doubled and a small decrease in O2 uptake is also observed. The data are consistent with the conversion of the metabolism of a population of glycogen-containing cells in the slises, upon incubation with dibutyryl cyclic AMP or TBMX + IPNE, from primarily oxidative metabolism using an extracellular glucose source to primarily glycolytic metabolism using the cells’ own glycogen stores. The findings reported here in vitro are in good agreement with studies reported in the literature concerning changes in the in vivo levels of brain glycogen and lactic acid in mice following the injection of drugs which act upon beta-adrenergic receptors.
Application of new technologies to studies of neural crest migration and differentiation.

This review describes the application of new techniques for examining some longstanding questions in the neural crest system concerning pathways of migration, cell lineage decisions, and importance of the extracellular matrix. The first issue examined involves the migratory pathways followed by neural crest cells. In birds, it has been possible to map crest migratory routes accurately using antibodies that selectively recognize neural crest cells. These antibodies permit the identification of migrating cells in the absence of the surgical trauma incurred by neural tube transplantations. In amphibian embryos, which are more readily accessible to embryological manipulation than are birds, neural fold grafts using two new cell markers have made it possible to map the early stages of neural crest migration using both interspecific and intraspecific chimerae. In both birds and amphibians, a metameric pattern of neural crest migration was observed; this presumably results from interactions with the adjacent somites. A second novel experimental paradigm tests the role of cell surface–extracellular matrix interactions in neural crest migration. Using antibodies to perturb interactions between the cell surface and the extracellular matrix selectively, it has been possible to identify some molecular interactions that are important for aspects of neural crest migration in situ. New techniques have also made it possible to examine the cell lineage decisions of neural crest cells. Using a retrograde labeling technique and a method of microinjecting cells into embryos, we have found that neural crest-derived cholinergic neurons remain plastic with respect to their neurotransmitter expression even after overt differentiation. New cell-marking techniques have made it possible to study neural crest cell lineage by means of clonal analysis. Individual neural crest precursors can be injected with a cell lineage tracer that is passed to all of its progeny. Thus, we can examine the developmental potential of individual neural crest cells. The various experimental paradigms presented in this review illustrate the utility of recent technological advances to study embryological questions that have long concerned investigators interested in the neural crest and in other developmental systems.
Full-order Extended High Gain Observers for a class of nonlinear systems

A full order observer is designed for a class of nonlinear systems that can potentially admit unstable zero dynamics. The structure of the observer is composed of an Extended High Gain Observer (EHGO), for the estimation of the derivatives of the output, augmented with an Extended Kalman Filter for the estimation of the states of the internal dynamics. The EHGO is also utilized to estimate a signal that renders the internal dynamics observable. In the special case of the system being linear in the internal dynamics, we managed to achieve semiglobal asymptotic convergence of the estimation error. We demonstrate the effectiveness of the observer by applying it to a Translating Oscillator with a Rotating Actuator (TORA) system.
Solving Bertolami's equations for Brans-Dicke cosmological models

Solutions are developed for Berman and Som's formulation of Bertolami's equations for a Brans-Dicke cosmology with time-dependent cosmological term. Physical constraints are applied to these solutions to deduce conditions necessary for constructing plausible cosmological models in this theory.
The Use of Environmental Features on Tactile Maps by Navigators Who Are Blind

Maps designed for and used by sighted audiences benefit from map symbol standardization and convention but, with very limited exception (most notably two European projects), neither standardization nor convention guides the design and use of symbols for tactile maps. In this project, we developed and field tested symbolization for and use of tactile street maps. The development process included consultation with the literature as well as with field experts (orientation and mobility teachers, Braillists, and teachers working with students who are blind or have low vision). Following development, we undertook a three-year field testing and validation phase, in which we conducted pilot testing and formal testing with travelers who are blind or have low vision. Research results reveal not only a discriminable and useful tactile symbol set but also environmental feature use by travelers who are blind or have low vision.
Studies of Adaptive Radiation Using Model Microbial Systems

Adaptive radiation is a fundamental process in the evolution of biodiversity. The effects of seasonality, resource partitioning, and spatial heterogeneity have been examined experimentally using evolving populations of microbes. In all environmental conditions examined, ecological interactions have large effect on the likelihood and outcome of adaptive radiation. Adaptive radiation in seasonal environments can arise because of demographic trade-offs and excretion of metabolites. Resource partitioning can occur even in the absence of temporal or spatial heterogeneity. Spatial heterogeneity arising via growth is sufficient to generate microenvironments and subsequent adaptive radiation. However, ecological interactions maintaining diversity can be sensitive to slight alterations of the environmental conditions. Laboratory populations of microbes are ideal model systems to test the factors essential for adaptive radiation.
The relationship between resting blood pressure and acute pain sensitivity: effects of chronic pain and alpha-2 adrenergic blockade

This study tested for alpha-2 adrenergic mediation of the inverse relationship between resting blood pressure and acute pain sensitivity in healthy individuals. It also replicated limited prior work suggesting this inverse blood pressure/pain association is altered in chronic pain, and provided the first test of whether chronic pain-related changes in alpha-2 adrenergic function contribute to these alterations. Resting blood pressure was assessed in 32 healthy controls and 24 chronic low back pain participants prior to receiving placebo or an intravenous alpha-2 adrenergic receptor antagonist (yohimbine hydrochloride, 0.4 mg/kg) in a randomized crossover design. Participants experienced three acute pain tasks during both sessions. A significant Systolic Blood Pressure × Participant Type × Drug interaction on finger pressure McGill Pain Questionnaire-Sensory ratings (P < .05) reflected significant hyperalgesic effects of yohimbine in chronic pain participants with lower systolic blood pressures (P < .05) but not those with higher systolic pressures, and no significant effects of yohimbine in controls regardless of blood pressure level. A Drug × Systolic Blood Pressure interaction on finger pressure visual analog scale unpleasantness indicated the inverse blood pressure/pain association was significantly stronger under yohimbine relative to placebo (P < .05). Significant Participant Type × Systolic Blood Pressure interactions (P’s < .05) were noted for finger pressure visual analog scale pain intensity and unpleasantness, ischemic pain threshold, and heat pain threshold, reflecting absence or reversal of inverse blood pressure/pain associations in chronic pain participants. Results suggest that blood pressure-related hypoalgesia can occur even when alpha-2 adrenergic systems are blocked. The possibility of upregulated alpha-2 adrenergic inhibitory function in chronic pain patients with lower blood pressure warrants further evaluation.
Oxygen separation membranes based on intergrowth structures

Abstract The perovskite-related intergrowth oxides Sr4(Fe,Co)6O13+δ and (La,Sr)n+1(Fe,Co)nO3n+1 (Ruddlesden–Popper (R–P) series) with n=1, 2, 3 have been investigated for use as oxygen separation membranes. The crystal chemistry, degree of oxygen nonstoichiometry δ, total conductivity, and oxygen permeability have been investigated to evaluate the feasibility of these compounds for oxygen permeation membranes. The oxygen permeation flux of the Sr4Fe6−yCoyO13+δ samples with y>1.8 is due to the presence of a secondary perovskite phase, which has higher oxygen flux than the intergrowth oxide Sr4Fe6−yCoyO13+δ with y≤1.5. While the n=2 and 3 members of the R–P series show oxygen flux values one order of magnitude lower than the perovskite phase SrCo0.8Fe0.2O3−δ, the n=1 member shows negligible oxygen permeability. The (La,Sr)3(Fe,Co)2O7−δ (n=2) phases show good structural stability at high temperature and in the pO2 range of the oxygen permeation measurements. The oxygen permeation flux is found to be bulk limited for La0.3Sr2.7Fe1.4Co0.6O7−δ and the ionic conductivity σi has been estimated by assuming that this observation is valid for the other n=2 compositions as well.
IN PURSUIT OF CONSUMER THEORY

The central problem area in marketing may be conceived as the analysis and satisfaction of the consumer-buyer in order to stimulate demand. In its most fundamental form, therefore, marketing is necessarily concerned with describing, explaining, and predicting the behavior of men as it pertains to the performance of marketing activities, including consumption. That is, marketing is necessarily concerned with the development of a general theory and within it, a theory of consumer behavior. In this article, the authors propose one possible foundation for a theory of consumer behavior. Towards this end, the nature of theory, the primary requirements of developing consumer theory and some of the problems presently encountered in meeting these requirements, are all considered. A theoretical approach which holds promise for overcoming these problems, relevant to theory-development requirements, is then presented.
Photoluminescence of patterned arrays of vertically stacked InAs/GaAs quantum dots

We report on photoluminescence measurements of vertically stacked InAs/GaAs quantum dots grown by molecular beam epitaxy on focused ion beam patterned hole arrays with varying array spacing. Quantum dot emission at 1.24 eV was observed only on patterned regions, demonstrating preferential nucleation of optically active dots at desired locations and below the critical thickness for dot formation at these growth conditions. Photoluminescence measurements as a function of varying focused ion beam irradiated hole spacing showed that the quantum dot emission intensity increased with decreasing array periodicity, consistent with increasing dot density.