cssi/SciSciGPT-SciSciNet huggingface dataset:
Weaning from Mechanical Ventilation

For most patients who require mechanical ventilation weaning and extubation is simple. In these patients a variety of strategies can be successful. In addition, sim ple criteria may predict when the patient is ready for extubation. For the small group of patients who require prolonged mechanical ventilation, however, contro versy exists about how best to remove ventilator sup port by weaning, and available data are sparse. Much of the controversy has centered on T-piece weaning ver sus intermittent mandatory ventilation. To date no con trolled study has demonstrated the superiority of either intermittent mandatory ventilation or T-piece weaning in difficult-to-wean patients. In the evolution of this con troversy, concern has developed over the potential for increased inspiratory work and expiratory resistance that may be associated with certain intermittent manda tory ventilation systems. The possibility that significant inspiratory work may occur during assist-control venti lation has also been demonstra...
Determinants of outcome following left ventricular aneurysmectomy

UNLABELLED The determinants of outcome after left ventricular aneurysmectomy are not well understood. We analyzed preoperative follow-up information on 38 patients who had undergone left ventricular aneurysmectomy. At a mean follow-up of 39 months (range 6 to 68), 25 patients (66%) improved by at least one functional class (New York Heart Association) (Group I), and 13 patients (Group II) either died (n: 8) or had persistent congestive heart failure (n: 5). Patients in Group I had significantly higher left ventricular ejection fraction before surgery than patients in Group II (38 +/- 12% vs. 29 +/- 14%, P less than 0.04). The volume of the aneurysm at end-diastole was smaller among patients in Group I than Group II (42 +/- 32 ml vs. 73 +/- 47 ml, P less than 0.04). The contractile indices of the nonaneurysm segment, contractile segment ejection fraction, basilar half ejection fraction, and basilar fractional area shortening were not significantly different between the two groups. There was no difference between the two groups in the preoperative left ventricular end-diastolic pressure, cardiac index, pulmonary artery wedge pressure, pulmonary artery pressure, extent of coronary artery disease, number of bypass grafts inserted, or aortic cross-clamp times. CONCLUSION 1) The ejection fraction and volume of the aneurysm are more important predictors of outcome after left ventricular aneurysmectomy than the contractile indices of the nonaneurysmal left ventricle and 2) symptomatic improvement occurs in 66% of patients after left ventricular aneurysmectomy.
Examination of the structural features that favor the columnar self-assembly of bis-urea macrocycles.

Second-generation self-assembling bis-urea macrocycles were designed that form columnar structures in the solid state. The new macrocycles were constructed from more flexible building blocks yielding greater solubility and a more efficient synthesis. In addition, heteroatoms in the form of ether oxygens were incorporated in the walls of the macrocycles to provide additional recognition sites for guest encapsulation. We observed reduced fidelity of the stacking motif and in some cases the intermolecular urea−urea hydrogen bonds were disrupted by the formation of intramolecular hydrogen bonds. We also observed new offset assembly motifs that maintained the urea−urea interaction. These results suggest that the stacking of the arene units in the rigid first-generation systems was an important factor in guiding the formation of the columnar stacks.
How somatotopic is the motor cortex hand area

The primary motor cortex (M1) is thought to control movements of different body parts from somatotopically organized cortical territories. Electrical stimulation suggests, however, that territories controlling different fingers overlap. Such overlap might be artifactual or else might indicate that activation of M1 to produce a finger movement occurs over a more widespread cortical area than usually assumed. These possibilities were distinguished in monkeys moving different fingers. Recordings showed that single M1 neurons were active with movements of different fingers. Neuronal populations active with movements of different fingers overlapped extensively. Control of any finger movement thus appears to utilize a population of neurons distributed throughout the M1 hand area rather than a somatotopically segregated population.
Semantic Operations in Aphasic Comprehension: Implications for the Cortical Organization of Language

We provide data on the neurological basis of two semantic operations at the sentence level: aspectual coercion and complement coercion. These operations are characterized by being purely semantic in nature; that is, they lack morphosyntactic reflections. Yet, the operations are mandatory (i.e., they are indispensable for the semantic well formedness of a sentence). Results indicate that, whereas Broca's patients have little or no trouble understanding sentences requiring these operations (performance was above chance for all conditions), Wernicke's patients performed at normal-like levels only for sentences that did not require these operations. These findings suggest that sentence-level semantic operations rely very specifically on the integrity of the cortical area associated with Wernicke's aphasia, but not on the region corresponding to Broca's aphasia. In the context of other findings from lesion and imaging studies, this evidence allows a view of the cortical distribution of language capacity that is drawn along a linguistic line, one which distinguishes syntactic from semantic operations.
JACKKNIFING TECHNIQUES FOR EVALUATION OF EQUATING ACCURACY

Grouped jackknifing may be used to evaluate the stability of equating procedures with respect to sampling error and with respect to changes in anchor selection. Properties of grouped jackknifing are reviewed for simple-random and stratified sampling, and its use is described for comparisons of anchor sets. Application is made to examples of item response theory (IRT) true-score equating in which two-parameter logistic and general partial credit models are employed.
Prolactin and growth hormone synthesis and thymidine incorporation in dissociated rat pituitary tumor cells.

The effect of in vivo diethylstilbestrol (DES) treatment on the MtT/W 15 transplantable pituitary tumor was examined in dissociated pituitarq cells by measuring the rate of incorporation of ('H)thqmidine into DNA and the synthesis of prolactin (PRL) and growth hormone (GH) as assessed by the rate of incorporation of ('H)leucine. MtTjW I5 transplantable pituitary tumors from rats treated for 3 weeks with DES showed significant reduction in the extent of ('Hlthymidine incorporation compared with tumor cells from untreated rats (2231 i 182 vs 172 k 17 dpm/lOS cells: n = 3). In addition. tumor cells from DES-treated rats showed a significant increase in GH synthesis compared with tumor cells from untreated rats. In contrast to these findings. dissociated pituitary cells from non-tumor-bearing rats given 10 mg DES in Silastic tubing for 3 weeks showed a three-fold increase in PRL synthesis compared to cells from untreated control rats (29.3 i 1.5 vs 10.0 i 0.9% of total radioactivit? in gel; n = 3. There was also a four-fold increase in the rate of ('H)th)midine incorporation after DES-treatment in non-tumor-bearing rats (695 i 114 vs 178 i 13.9 dpm/105 cells: n = 3). These results indicate that DES inhibits MtTjWl5 pituitary tumor cell proliferation. wjhile stimulating synthesis of GH. c 1986 Society for Experimental Biology and Medicine
In vivo or in vitro exposure to imipramine reduces α2-adrenoceptor-mediated inhibition of cyclic AMP production in rat brain cerebral cortical slices

The effect of in vivo or in vitro exposure to imipramine on α2-adrenoceptor-mediated inhibition of cAMP production in rat brain slices was examined. Chronic administration (10 mg/kg once daily for 14 or 21 days) of imipramine or in vitro exposure (100 μM, 60 min) to the antidepressant significantly reduced the ability of UK-14,304, an α2-adrenoceptor agonist, to inhibit forskolin-stimulated cAMP accumulation in cerebral cortical slices. This reduction was due to a decrease in the maximal response to the α2-adrenergic agonist rather than to a decrease in its potency. Besides yielding a rapid and direct method for studying the effect of imipramine on brain receptors in vitro, these findings provide biochemical evidence in support of the notion that this drug, and perhaps other antidepressants, modifies α2-adrenoceptor function in the central nervous system.
Normally-off 5A/1100V GaN-on-silicon device for high voltage applications

We report the DC and switching performance of a normally-off 5A/1100V GaN-on-Si device. The device had a breakdown field of 95V/µm and a V B 2/R on,sp of 272MW/cm2. A 360V/180W boost converter was operated at 200KHz, with an efficiency ≫92%. Respectively, these values are the highest for a normally-off GaN-on-Si device.
Functional Loads of the Tongue and Consequences of Volume Reduction

Purpose This study was conducted to evaluate functional loads of the tongue on its surrounding bones and investigate how tongue volume reduction affects these loads. Materials and Methods Masticatory bone strains and pressures on facial bones directly contacted by the tongue were measured in 12 (6 sibling pairs) 12-week-old Yucatan miniature pigs. One of each sibling pair underwent surgery to reduce the tongue volume by 23% to 25% (reduction group); the other underwent identical tongue incisions without tissue removal (sham group). Rosette strain gauges were bonded to the palatal surface of premaxilla (PM), the lingual surface of mandibular alveolar bones between the second and third decidious incisors (MI), and below the third decidious molar (MM). Single-element stain gauges were placed across the palatal surface of the premaxillary stuture (PMS) and the lingual surface of the mandibular symphysis (MSP). Pressure tranducers were placed on the hard palatal surface of the maxillary (PAL) and the lingual surface of the mandible (MAN) posterior to the deciduous canine. Animals were allowed to feed unrestrainedly after surgery and device placement. Data from bone strain, pressure, and electromyographic (EMG) activity of bilateral masseter muscles were recorded during natural mastication (pig chow). Results In the sham animals, the principal bone surface strains were less than 100 μe in all measures. The principal strains were greater compressive than tensile strains at the PM and greater tensile than compressive strains at the MI and MM. Tensile strains were significantly greater at the MM than at the PM (P 100 μe) at the PMS (P Conclusions These results suggest that 1) the tongue produces greater functional loads (strains and pressures) on mandibular lingual surfaces than on maxillary/premaxillary palatal surfaces; 2) tongue volume reduction decreases these loads, specifically those in the anterior mouth; and 3) masticatory loads produced by the tongue on the lingual mandibular and palatal maxillary/premaxillary surfaces are much smaller than those produced by masticatory muscles on the dorsal surfaces of these bones and temporomandibular joint structures.
Site-directed mutagenesis of maize recombinant C4-pyruvate,orthophosphate dikinase at the phosphorylatable target threonine residue

A key regulatory enzyme of the C4-photosynthetic pathway is stromal pyruvate,orthophosphate dikinase (PPDK, EC 2.7.9.1). As a pivotal enzyme in the C4 pathway, it undergoes diurnal light–dark regulation of activity which is mediated by a single bifunctional regulatory protein (RP). RP specifically inactivates PPDK in the dark by an ADP-dependent phosphorylation of an active-site Thr residue (Thr-456 in maize). Conversely, RP activates inactive PPDK in the light by phosphorolytic dephosphorylation of this target Thr-P residue. We have employed a His-tagged maize recombinant C4 PPDK for directed mutagenesis of this active-site regulatory Thr. Three such mutants (T456V, T456S, T456D) were analyzed with respect to overall catalysis and regulation by exogenous maize RP. Substitution with Val and Ser at this position does not affect overall catalysis, whereas Asp abolishes enzyme activity. With respect to regulation by RP, it was found that Ser can effectively substitute for the wild-type Thr residue in that mutant enzyme is phosphorylated and inactivated by RP. The T456V mutant, however, could not be phosphorylated and was, thus, resistant to ADP-dependent inactivation by RP.
The Color of Sin White and Black Are Perceptual Symbols of Moral Purity and Pollution

Three studies examined automatic associations between words with moral and immoral meanings and the colors black and white. The speed of color naming in a Stroop task was faster when words in black concerned immorality (e.g., greed), rather than morality, and when words in white concerned morality (e.g., honesty), rather than immorality. In addition, priming immorality by having participants hand-copy an unethical statement speeded identification of words in the black font. Making immorality salient in this way also increased the moral Stroop effect among participants who had not previously shown it. In the final study, participants also rated consumer products. Moral meanings interfered with color naming most strongly among those participants who rated personal cleaning products as especially desirable. The moderation of the moral Stroop effect by individual differences in concerns about personal cleanliness suggests that ideas about purity and pollution are central to seeing morality in black and white.
Amino-acid sequence of a cooperative, dimeric myoglobin from the gastropod mollusc, Buccinum undatum L.☆

Abstract The complete amino-acid sequence of a dimeric myoglobin from the radular mussel of the gastropod mollusc, Buccinum undatum L. has been determined. The globin1, which shows cooperative binding of oxygen, contains 146 amino acids, is N-terminal aminoacetylated, and has histidine residues at position 65 and 97, corresponding to the heme-binding histidines seen in mammalian myoglobins. It shows about 75% and 50% homology, respectively, with the dimeric molluscan myoglobins from Busycon canaliculatum and Cerithidea rhizophorarum, the former of which also shows weak cooperativity, but much less similarity to other species of myoglobin and hemoglobin.
The Perils of Predicting Proliferation

Studies of nuclear proliferation share five serious problems. First, nuclear programs' initiation and completion dates are ambiguous and difficult to code, but findings are rarely subjected to sufficient robustness tests using alternative codings. Second, independent variables overlook important factors such as prestige and bureaucratic power and often use poor proxies for concepts such as the nonproliferation regime. Third, methodologies and data sets should be tightly coupled to empirical questions but are instead often chosen for convenience. Fourth, some findings provide insights already known or believed to be true. Fifth, findings can ignore or gloss over data crucial for policy making and wider debates. This article reviews new quantitative research on nuclear proliferation, noting improved analysis and lingering problems. It highlights the 1999 Kargil war to explore dangers of relying on stock data sets and the need for research on statistical outliers. It concludes with a future research agenda a...
Mechanistic investigation of the stimulus properties of 1-(3-trifluoromethylphenyl)piperazine.

Using a standard two-lever operant procedure with rats trained to discriminate 1-(3-trifluoromethylphenyl)piperazine (TFMPP) (0.5 mg/kg) from saline, tests of stimulus antagonism and stimulus generalization were performed to better understand the stimulus properties of this agent. The agents examined for ability to antagonize the TFMPP stimulus were prazosin, quipazine, zacopride, buspirone, 8-hydroxy-2-(di-N-propylamino) tetralin (8-OH-DPAT), 1-(2-methoxyphenol)-4-[4-(2-phthalimido)butyl]-piperazine (NAN-190), haloperidol, and 1-(2-pyrimidinyl)piperazine (1-PP); only buspirone attenuated the response to TF-MPP. In separate experiments, the lowest nondisrupting dose of buspirone (1.2 mg/kg) caused a rightward shift of the TFMPP dose-response curve (TFMPP alone, ED50 = 0.19 mg/kg; TEMPP + buspirone, ED50 = 0.43 mg/kg).. In addition, 3-(1,2,5,6-tetrahydropyrid-4-yl)pyrrolo[3,2-b]pyrid-5-one (CP 93,129), 7-trifluoromethyl-4-(4-methyl-1-piperazinyl)pyrolo [1,2-a]quinoxaline (CGS 12066B), 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), 3-chlorophenylbiguanide (mCPBG), NAN-190, nisoxetine, zacopride, 1-PP, (+)-N-allylnormetazocine ((+)-NANM), and N-methyl31-(3,4-methylenedioxyphenyl)-2- aminopropane (MDMA) were analyzed in tests of stimulus generalization. The TFMPP stimulus generalized only to CGS 12066B (ED50 = 4.2 mg/kg) and (+)-NANM (ED50 = 8.8 mg/kg). Tests with DOI and MDMA resulted in partial generalization. Up to doses that disrupted behavior, all other agents had little effect on TFMPP-appropriate responding. The results of these and other published studies suggest roles for 5-hydroxytryptamine1B (5-HT1B), 5-HT1C, and, possibly, σ-receptors in the mediation of the TFMPP stimulus and indicate a lack of involvement of 5-HT1A, 5-HT2, dopaminergic, and adrenergic mechanisms in this behavior.
An improved synthesis of dihydroxyacetone phosphate

Abstract An improved procedure has been developed for the synthesis of dihydroxyacetone phosphate (DHAP). Reaction of 2,5-diethoxy-p-dioxane-2,5-dimethanol ( 1 ) and the trivalent phosphorylating reagent dibenzyl-N,N-diethylphosphoramidite (DDP) in the presence of 1,2,4-triazole or tetrazole followed by oxidation with H 2 O 2 gave 2,5-diethoxy-p-dioxane-2,5-dimethanol-O-2 1 -O-5 1 - bis(phosphate) tetrabenzyl ester ( 2 ) in 98% yield. Compound 2 was then hydrogenated in the presence of H 2 -Pd/C to give, after neutralization, 2,5-diethoxy-p-dioxane-2,5-dimethanol-O-2 1 -O-5 1 -bis(phosphate) as a stable trisodium salt ( 3 ) in 84% yield. Treatment of 3 with Dowex 50 (H+) generates 2 equivalents of DHAP.
Magnetic circularly polarized emission from crystalline Cs2GeF6:Mn4+

Abstract High resolution, low temperature magnetic circularly polarized emission (MCPE) measurements are reported for 4 A 2g ← 2 E g of Cs 2 GeF 6 :Mn 4+ with analysis of the 0-0 (including MCD) and 0-1 (t 2u ) vibronic components. MCPE is found to be a highly sensitive technique for studying these weak transitions.
Androgen-induced gene activation in the rat prostate.

Abstract The effect of androgens on gene activation in the rat prostate has been investigated by examining precursor incorporation into RNA, by DNA-RNA hybridization of RNA transcribed in vitro from prostate chromatin, and by thermal denaturation of prostatic chromatin. The results show a selective synthesis of nuclear RNA and a changed thermal melting profile of prostatic chromatin as a result of testosterone administration. Further, the in vitro synthesized RNA transcribed from prostatic chromatin of androgen-treated rats contained new RNA species that were not transcribed from chromatin of untreated castrated controls. The data provide direct evidence for an activated state of the prostatic chromatin stimulated by androgens.
Characterization of persistent intermediates generated upon inclusion of 1,1-diarylethylenes within CaY zeolite: Spectroscopy and product studies

Inclusion of 1,1-diarylethylenes within activated CaY results in the formation of colored samples that are stable for prolonged periods. For example, diphenylethylene generates a green color within CaY. Two reactive intermediates have been shown to be responsible for this color. The species with the short wavelength ({lambda}{sub max} 410 nm) absorption has been established to be the diphenylmethyl cation. The identity of the species with the long wavelength ({lambda}{sub max} 620 nm) absorption has been debated for three decades. The authors establish that the diarylethylene radical cation is not responsible for the long wavelength absorption. Laser flash photolysis studies show that a number of diarylethylene radical cations have a characteristic absorption in the 400 nm region in both solution and in NaY zeolite. The absence of this absorption for diarylethylene-CaY samples unequivocally eliminates the possibility that these radical cations are responsible for color formation. This is substantiated by the fact that a number of 2-methyl-substituted 1,1-diarylethylenes generate only the short wavelength cation absorption upon inclusion in CaY; radical cation formation would be expected to be equally facile for the methyl-substituted derivatives. The results suggest that an allylic dimer cation is the most likely source of the long wavelength ({lambda}{sub max}more » 620 nm) absorption within CaY.« less
Tonic Chemoreflex Activation Does Not Contribute to Elevated Muscle Sympathetic Nerve Activity in Heart Failure

Background Sympathetic activation in heart failure may be due to an increase in sympathetic excitatory influences or to a decrease in inhibitory signals to the brain stem. Chemoreflex sensitivity may be increased in patients with heart failure. The present study tested the hypothesis that tonic activation of excitatory chemoreceptor afferents contributes to the elevated sympathetic activity in heart failure. Methods and Results We recorded sympathetic nerve activity to muscle circulation from the peroneal nerve of 12 chronic heart failure patients while the patients were breathing room air and during deactivation of the chemoreceptors while the patients were breathing a 100% O2 gas mixture. All patients except 2 were in class III of the New York Heart Association functional classification. Left ventricular ejection fraction defined by radionuclide ventriculography was 24±2% (mean±SE). We also obtained measurements of resting sympathetic nerve activity in 9 healthy control subjects to document that sympath...
Geomorphic aspects of groundwater flow

The many roles that groundwater plays in landscape evolution are becoming more widely appreciated. In this overview, three major categories of groundwater processes and resulting landforms are considered: (1) Dissolution creates various karst geometries, mainly in carbonate rocks, in response to conditions of recharge, geologic setting, lithology, and groundwater circulation. Denudation and cave formation rates can be estimated from kinetic and hydraulic parameters. (2) Groundwater weathering generates regoliths of residual alteration products at weathering fronts, and subsequent exhumation exposes corestones, flared slopes, balanced rocks, domed inselbergs, and etchplains of regional importance. Groundwater relocation of dissolved salts creates duricrusts of various compositions, which become landforms. (3) Soil and rock erosion by groundwater processes include piping, seepage erosion, and sapping, important agents in slope retreat and headward gully migration. Thresholds and limits are important in many chemical and mechanical groundwater actions. A quantitative, morphometric approach to groundwater landforms and processes is exemplified by selected studies in carbonate and clastic terrains of ancient and recent origins.
Benefits of an Ed.D. program in deaf education: a survey.

Ten graduates and 3 ABD (all but dissertation) students in Lamar University's doctoral program in deaf studies/deaf education were surveyed about their perceptions of the benefits of earning a doctorate of education (Ed.D.) in their field. The program comprised course work on current content information on deaf education, an educational research component, a cognate area, and electives. As part of the program, researchers and scholars in areas related to deaf education were invited to campus to consult with doctoral students. Graduates found jobs at universities, community colleges, and departments of special education. Graduates ranked program components on the basis of perceived value; they rank-ordered the courses on the basis of their value to them in their current work. Graduates also commented on how the program enhanced their professional growth.
Contributions of individual variation in temperature, solar radiation and precipitation to crop yield in the North China Plain, 1961–2003

An understanding of the relative impacts of the changes in climate variables on crop yield can help develop effective adaptation strategies to cope with climate change. This study was conducted to investigate the effects of the interannual variability and trends in temperature, solar radiation and precipitation during 1961–2003 on wheat and maize yields in a double cropping system at Beijing and Zhengzhou in the North China Plain (NCP), and to examine the relative contributions of each climate variable in isolation. 129 climate scenarios consisting of all the combinations of these climate variables were constructed. Each scenario contained 43 years of observed values of one variable, combined with values of the other two variables from each individual year repeated 43 times. The Agricultural Production Systems Simulator (APSIM) was used to simulate crop yields using the ensemble of generated climate scenarios. The results showed that the warming trend during the study period did not have significant impact on wheat yield potential at both sites, and only had significant negative impact on maize yield potential at Beijing. This is in contrast with previous results on effect of warming. The decreasing trend in solar radiation had a much greater impact on simulated yields of both wheat and maize crops, causing a significant reduction in potential yield of wheat and maize at Beijing. Although decreasing trends in rainfed yield of both simulated wheat and maize were found, the substantial interannual variability of precipitation made the trends less prominent.
Repeat gamma knife radiosurgery for trigeminal neuralgia.

Background Trigeminal neuralgia (TN) may recur after treatment by gamma knife stereotactic radiosurgery (GKSR). Objective To evaluate management outcomes in patients who underwent repeat GKSR for TN. Methods The authors reviewed their experience with repeat GKSR in 119 patients with recurrent TN. The median patient age was 74 years (range, 34-96 years). The median interval between procedures was 26 months. The median target dose for repeat GKSR was 70 Gy (range, 50-90 Gy) and the median cumulative dose was 145 Gy (range, 120-170 Gy). The median follow-up was 48 months (range, 6-187 months) after repeat GKSR. Results After repeat GKSR, 87% of patients achieved initial pain relief (Barrow Neurological Institute pain score I-IIIb). Pain relief was maintained in 87.8% at 1 year, 69.8% at 3 years, and 44.2% at 5 years. Facial sensory dysfunction occurred in 21% of patients within 18 months after GKSR. Longer pain relief was observed in patients who had recurrent pain in a reduced pain distribution of the face compared with the pain distribution at the time of their initial GKSR, and in those who developed additional trigeminal sensory loss after a repeat procedure. A cumulative edge of brainstem dose ≥ 44 Gy was more likely to be associated with the development of sensory loss. Conclusion Repeat GKSR provides a similar rate of pain relief as the first procedure. The best responses were observed in patients who had good pain control after the first procedure and those who developed new sensory dysfunction in the affected trigeminal distribution.
Inflammation modulates the contribution of receptor-subtypes to bradykinin-induced hyperalgesia in the rat

While B2 receptors mediate pain and hyperalgesia induced by bradykinin, in normal rats, recent reports indicate that, in the setting of inflammation, B1 receptors also mediate pain and hyperalgesia. Since bradykinin-induced hyperalgesia in normal rats is mediated by prostaglandins released from the postganglionic sympathetic neurons, we have evaluated the contribution of the sympathetic nervous system to the hyperalgesia induced by bradykinin, a preferential B2-receptor agonist, and des-Arg9-bradykinin, a major metabolite of bradykinin and a selective B1-receptor agonist. Mechanical hyperalgesia was quantified by the Randall-Selitto paw-withdrawal method. Inflammation was induced by injecting Complete Freund's Adjuvant into the left hindpaw of the rat and testing mechanical nociceptive threshold in the right hindpaw after injecting B1 or B2 agonists and/or antagonists. Sympathectomy was achieved by surgically removing sympathetic ganglia L1-L4. Rats were used 48 h post-adjuvant injection. In the normal rat, intradermal injection of bradykinin but not des-Arg9-bradykinin, into the dorsal surface of the hindpaw, produced a dose-dependent decrease in mechanical nociceptive threshold. NPC 17731, a B2-receptor antagonist, but not des-Arg9-[Leu8]-bradykinin, a B1-receptor antagonist, almost completely inhibited the decrease in mechanical threshold, suggesting that bradykinin hyperalgesia in the normal rat hindpaw was mediated by B2 receptors. In rats whose left paws were treated, 48 h earlier, with adjuvant, intradermal injection of bradykinin or des-Arg9-bradykinin, into the right paw produced dose-dependent hyperalgesia. Bradykinin hyperalgesia was partially inhibited by NPC 17731, and the residual part by des-Arg9,[Leu8]-bradykinin. des-Arg9-bradykinin hyperalgesia was inhibited by des-Arg9,[Leu8]-bradykinin but not by NPC17731. These results suggest that in the setting of inflammation, bradykinin hyperalgesia was mediated by both B1 and B2 receptors, and that des-Arg9-bradykinin hyperalgesia was mediated by the B1 receptor. Forty-eight hours after injection of complete Freund's adjuvant, in sympathectomized rats, bradykinin or des-Arg9-bradykinin failed to produce hyperalgesia, suggesting that intact sympathetic postganglionic neurons are required for the hyperalgesia produced by these agents in this model. These results are consistent with the suggestions that B2 receptors mediate bradykinin-induced cutaneous hyperalgesia in the normal rat hindpaw. The hyperalgesia induced by bradykinin, 48 h post injection of complete Freund's adjuvant is mediated by both B1 and B2 receptors, that by des-Arg9-bradykinin is mediated by B1 receptors. The hyperalgesia induced by both agents is dependent on the presence of intact sympathetic postganglionic neurons.
Gallium in Flue Dust

MR. W. KIRBY'S observation of the occurrence of the element mercury in coal-tar, recorded by Dr. Aston in NATURE of April 2, p. 489, is another instance of the wide distribution of an element in minute quantity. Employing the method of spectrum analysis by oxy-hydrogen or oxy-coal gas flames (Hartley and Ramage, Trans. Chem. Soc., 71, 533, 1897, etc.) in a search for sources of potassium in flue dusts during the War, certain samples were found to contain notable quantities of gallium. Experiments have been made as occasion permitted to perfect a method for extracting that rare metal from Norwich Gas Works' flue dust, derived from South Yorkshire coal, and in the course of the work the presence of the following elements has been noted: lithium, sodium, potassium, rubidium, cesium, copper, silver, calcium, strontium, zinc, aluminium, gallium, indium, thallium, carbon, titanium, silicon, lead, vanadium, phosphorus, arsenic, antimony, bismuth, oxygen, chromium, molybdenum, sulphur, manganese, chlorine, iron, and nickel. Circumstances have not permitted a complete analysis to be made, and one substance, at least, awaits final purification and identification. Certain selected pieces of dust, partially fritted, apparently contain about 2 per cent. of gallium, and the proportions of zinc and vanadium are probably higher still.
On the increasing importance of constraints

In this paper, we examine how the addition of rolebased access control (RBAC) model features affect the complexity of the RBAC constraint models. Constraints are used in RBAC models to constrain the assignment of permissions and principals to roles (among other things). Historically, it was assumed that the role assignments would change rather infrequently, so only a few constraints were necessary. Given new RBAC features, such as context-sensitive roles, the complexity of the restrictions that can be required is increasing because the role definitions may depend on application state. As application state changes, so do the role assignments. We examine the RBAC constraint problem using an example of a virtual university. We propose RBAC model features for simplifying the representation of constraints given our experience with this example.
Preparation of a tetraphenylethylene-based emitter: Synthesis, structure and optoelectronic properties of tetrakis(pentaphenylphenyl)ethylene

Soluble tetrakis(pentaphenylphenyl)ethylene (1), prepared in three steps, allows non-emissive tetraphenylethylene (TPE) to turn into an emitter (ΦF = 0.13) owing to the steric bulk of the four large hexaphenylbenzene propellers which hamper C–Ph and CC bond rotations in the TPE core.
A Power Bipolar Transistor Optimized for Linear Performance up to 5 GHz

A linear power transistor with 1.6 ?m emitter width, 34 emitter sites, and individual emitter ballast resistors has been developed using a new transistor process which has excellent reproducibility. Such a transistor has been packaged with a single stage of input matching which transforms the input impedance to an easily usable value in the 4 GHz region. Experimental linear output power of 500 mW has been measured with a corresponding gain of 7.5 dB at the 1 dB gain compression point at 4 GHz, and with useful gain and power at 5 GHz. Data is presented on the transistor's linear power performance, S-parameters from 2 to 5 GHz, and third-order intercept points.
Counting the number of classes in a fuzzy set

The issue of counting the number of elements in fuzzy set is discussed. The issue of counting the number of equivalence classes in a fuzzy subset is investigated. The more general problem of counting how many similarity classes are present in a fuzzy subset is then examined. This becomes a very complex problem because of the lack of distinct boundaries in the similarity classes. >
Risk Behaviors and Resiliency within Physically Abused Adolescents.

OBJECTIVE: This study examines the relationship between physical abuse and several risk behaviors, and thriving behaviors, and the relationship between potential protective factors and engagement in risk and thriving behaviors among victims of physical abuse. Three categories of potential protective factors were examined: (1) individual characteristics, (2) family processes, and (3) extra-familial factors. We expected that high levels of protective factors would reduce engagement in risk behaviors (i.e., alcohol use, tobacco use, drug use, sexual activity, antisocial behavior, attempted suicide, and purging) among abused adolescents. RESULTS: Across all the risk behaviors, abused adolescents reported a higher frequency of engagement than non-abused adolescents. Several protective factors were identified for the seven risk behaviors. Peer group characteristics was a significant predictor in all seven of the logistic regressions, followed by positive school climate (six models), religiosity (five models), other adult support (five models), family support (four models), view of the future (two models), and involvement in extra-curricular activities (two models). The variance accounted for by the models ranged from 2% (risk behavior of purging) to 26% (risk behavior of alcohol use and antisocial behavior). CONCLUSIONS: The findings indicate that, with the exception of sexual activity, the majority of abused adolescents were not engaging in risk behaviors; however, significantly more abused adolescents were engaging in risk behaviors than their non-abused counterparts. In addition, that protective factors were found to exist at various levels of the adolescents' ecology has strong implications for practice. Language: en
Postmodern software development

Art encompasses aesthetic metrics such as beauty, intellectual progression, and quality of workmanship. Engineering includes reliability and economy of construction. We expect our software systems to satisfy a large range of "-ilities," including an aesthetic of understandability; ease of construction, maintenance, and evolvability; an economy of execution; reliability; security from attack; interoperability; and so forth. Psychology's dual role in software systems plays out in both software creation and use. The history of software development includes elements of art, science, engineering, and fashion (though very little manufacturing). In software, the early emphasis on functional development yielded to structured programming, and, over the past 20 years, the rise of computer science's modernism: object-oriented technology.
A dissection of steps leading to viral envelope protein-mediated membrane fusion.

increase in [Ca”] at the presynaptic nerve terminal sets a complex set of biochemical events in motion that finally terminates in the specific fusion of the membrane of the secretory vesicle with the plasma membrane.’ In studying the action of CaZ+ at the presynaptic terminal a distinction has to be made between processes that occur in the cytosol that result in the triggering of the fusion event, and the final membrane fusion event itself. Although specific fusogenic proteins have been postulated to mediate exocytotic membrane fusion, the molecular components of exocytotic membrane fusion machinery remain to be identified. Our own studies have focused on pH-regulated viral fusion for which the participatory proteins have been identified.’ The first steps in infection of animal cells by enveloped virus are binding and fusion of the cell and viral membranes? Those events are mediated by viral envelope glycoproteins. Some virus strains infect cells by acid-activated fusion following endocytosis
Evolution and functional significance of tendon ossification in woodcreepers (Aves: Passeriformes: Dendrocolaptinae).

The woodcreepers, a clade of scansorial, neotropical birds, are distinctive among passerines in having extensive tendon ossification. Dissection of 42 of the 50 species indicates that such ossification in the hindlimb is limited almost entirely to tendons of insertion of the crural muscles. Most crural muscles have ossifications, and in all but one the ossified tendons are long and thin. Preliminary dissection revealed a similar pattern among ossified wing tendons. Phylogenetic analysis suggests that extensive tendon ossification is a synapomorphy of the woodcreepers. The species of Dendrocincla, which form a clade, show secondary reduction of ossification in some tendons, which may be correlated with increased intraspecific variation and with an expansion of foraging habits and postures to include nonscansorial behaviors. In contrast, the larger woodcreepers, other than Drymornis bridgesii and Nasica longirostris, form a clade with virtually no loss in ossification or evidence of intraspecific variation, even in large series of two species. Phylogenetic losses do not occur for the primary flexor of the ankle (M. tibialis cranialis), whereas two extensors (Mm. fibularis longus and gastrocnemius pars lateralis) show a complex pattern of derivation and loss. Previous biomechanical studies demonstrate that ossification increases the stiffness of tendons, making them stretch less under a given force. These structural and phylogenetic patterns are consistent with the view that hindlimb tendon ossification in woodcreepers is an adaptation to resist increased forces that act to extend the limb during vertical climbing. © 1993 Wiley-Liss, Inc.
α‐Factor directed expression of the human epidermal growth factor in Saccharomyces cerevisiae

Expression kinetics of the human Epidermal Growth Factor (hEGF) from the alpha-factor prepro region in a 2-mum based plasmid was studied in Saccharomyces cerevisiae. Production of hEGF was highly medium de pendent as a chemically defined, nonenriched media had a significantly lower yield than did enriched media. Also cells grown on yeast nitrogen base without amino acids with casamino acids degraded the hEGF after cell growth as opposed to a yeast extract, peptone, and dextrose (YEPD) medium, which elicited no measurable extracellular proteolysis of the hEGF. alpha-factor directed production kinetics of hEGF on the YEPD medium were growth associated, secretion limitations and extracellular degradation were negligible, and the hEGF was nearly 100% selectively secreted. With sufficient agitation, shake flask experiments were representative of aerated controlled batch fermentations. No effect of high cell density was observed on cell growth or hEGF production kinetics. The hollow fiber bioreactor had no direct effect on the substrate or protein yields of S. cerevisiae, however the low oxygen transfer capacity of the membrane was not sufficient to support respiration.
Modelling and simulation of communications network planning

In the design of a telecommunications network, we are given a set of nodes and the required number of channels connecting some pairs of nodes. The problem is to determine the layout of the channels of communication, satisfying the channel requirements at minimum cost. In this paper, we consider different approaches to the problem and concentrate mainly on experimental aspects on medium size networks.
Accuracy of stent measurements using ECG-gated greyscale intravascular ultrasound images: a validation study.

Abstract Greyscale intravascular ultrasound (IVUS) is an accurate tool for measuring stent dimensions and residual disease at the stent edge. Electrocardiographically (ECG)-gated IVUS is used in evolving second-generation IVUS systems, but this modality provides fewer greyscale cross-sectional images, and its accuracy to measure stent dimensions has not been assessed. This study was designed to validate the use of ECG-gated greyscale IVUS in measuring minimum stent area (MSA), stent length and reference dimensions compared to standard greyscale IVUS data. IVUS imaging was performed after drug-eluting stent implantation in 53 target lesions in 48 patients with acute coronary syndrome. The IVUS catheter was mechanically withdrawn at 0.5 mm/s, standard greyscale images were collected at 10 frames/s, and ECG-gated greyscale images were constructed from R-wave gated images. The MSA measured 6.20 ± 1.75 mm 2 vs . 5.98 ± 1.55 mm 2 on standard greyscale and ECG-gated greyscale IVUS, respectively (R 2 = 0.91, p = 0.005). The MSA position (R 2 = 0.66, p = 0.179) and stent length (R 2 = 0.99, p = 0.435) measurements were similar between modalities. Proximal reference vessel area was larger by ECG-gated IVUS, but proximal reference lumen and distal reference measurements were similar. Bland-Altman plots demonstrated good agreement between modalities. In conclusion, ECG-gated greyscale IVUS provides accurate and reliable measurements of stent length, area and reference segment plaque burden after stent implantation and is not inferior to standard greyscale IVUS. (E-mail: gsm18439@aol.com or gmintz@crf.org ).
Quantum spin memories and dot lattice polaritons in planar microcavities

Proposals for quantum computers based on spin degrees of freedom require that individual qubits are placed close enough so to have a significant exchange interaction between them. We have found theoretically that mixed light-matter states (polaritons) in planar microcavities can give an extremely long range spin coupling. This implies that spin qubits can be located several hundreds of nanometers apart while still retaining control on pair interaction through the use of polaritons. This spin control scheme can be scaled to an array of qubits in a quantum dot lattice. We have theoretically investigated a lattice of identical quantum dots (or impurity states) coupled to two dimensional photon modes in a planar cavity. This geometry can be used to design polaritons with novel properties, based on the spatial modulation of the exciton wave function in the plane of the dots. The application of this structure to the realization of spin-qubit quantum memories will be discussed.
Recognition memory reveals just how CONTRASTIVE contrastive accenting really is

The effects of pitch accenting on memory were investigated in three experiments. Participants listened to short recorded discourses that contained contrast sets with two items (e.g. British scientists and French scientists); a continuation specified one item from the set. Pitch accenting on the critical word in the continuation was manipulated between non-contrastive (H* in the ToBI system) and contrastive (L+H*). On subsequent recognition memory tests, the L+H* accent increased hits to correct statements and correct rejections of the contrast item (Experiments 1-3), but did not impair memory for other parts of the discourse (Experiment 2). L+H* also did not facilitate correct rejections of lures not in the contrast set (Experiment 3), indicating that contrastive accents do not simply strengthen the representation of the target item. These results suggest comprehenders use pitch accenting to encode and update information about multiple elements in a contrast set.
Correlation between Spin Polarization of Tunnel Currents from 3 d Ferromagnets and Their Magnetic Moments

We report measurements of spin-polarized tunnel currents from a wide compositional range of alloys of Ni with Fe, Mn, Cr, or Ti. The interpretation of the data indicates that all the alloys have an electron spin polarization $P$ which is positive and whose magnitude follows closely the saturation magnetic moment of the alloy. This simple result greatly constrains possible explanations of spin-polarized tunneling from $3d$ ferromagnetic metals.
Reconfirmation of the Short-Term Storage Concept

Recent research questions the existence of a short-term storage mechanism capable of holding limited information temporarily Specifically, serial-recall results with a through-list distractor (TLD) procedure, in which a distracting task is interposed between list items as well as between the list and recall period, generally resemble the results of immediate-recall procedures The present study, however, reconfirms the utility of short-term storage by demonstrating an important difference between immediate and TLD recall A word-length effect, or advantage for lists of shorter words (which minimize short-term forgetting during spoken recall), did not occur with a TLD procedure
Femtosecond temporal spectroscopy and direct inversion to the potential: Application to iodine

Abstract The use of femtosecond lasers in probing molecular dynamics is usually thought to yield improved temporal resolution, at the expense of spectral information. Here, we report on the use of femtosecond temporal spectroscopy (FTS) to yield accurate spectral information (vibrational and rotational) and to invert directly to the potential energy curve. As an example, we present the FTS analysis, inversion to the potential, and confirmatory wave packet calculations for the B 3 Π 0+u state of molecular iodine.
A spectral estimation technique to improve the efficiency of FDTD method for narrow-band microwave circuits

With the advances in computer technology, the finite-difference time-domain (FDTD) method is becoming increasingly popular in the analysis of microwave circuits. A major drawback of the conventional Yee FDTD implementation is the enormous time and memory required to characterize the resonant behavior of narrow-band circuits. In this paper, we introduce a technique which effectively employs a combination of Prony's extrapolation and adaptive sampling of the temporal data to reduce the number of FDTD iterations for resonant circuits. The new technique is applied to the characterization of a multilayered coplanar waveguide filter element. >