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We study the nonequilibrium dynamics of a quantum system under the influence of two noncommuting fluctuation sources, i.e., purely dephasing fluctuations and relaxational fluctuations. We find that increasing purely dephasing fluctuations suppress increasing relaxation in the quantum system. This effect is further enhanced when both fluctuation sources are fully correlated. These effects arise for medium to strong primary fluctuations already when the secondary fluctuations are weak due to their noncommuting coupling to the quantum system. Dephasing, in contrast, is increased by increasing any of the two fluctuations. Fully correlated fluctuations result in overdamping at much lower system-bath coupling than uncorrelated noncommuting fluctuations. In total, we observe that treating subdominant secondary environmental fluctuations perturbatively leads, as neglecting them, to erroneous conclusions.

Objective Sugar-sweetened beverage (SSB) consumption is cited as a major contributor to the U.S. obesity epidemic. The objective of this paper was to leverage insights from behavioral economics to examine whether nudges would entice college students to save meal calories by choosing water over SSBs. Methods Three message-based nudge interventions, with washout periods between, were used during the 7-week study. Calorie savings (self-interest), charity (prosocial), or charity-plus-calorie message posters were displayed in a college-based food franchise. Multilevel logistic regressions compared the proportions of students choosing water during three experimental conditions. This study assessed whether the frequency of dining establishment visits over the study period moderated effects of the experimental conditions on beverage choices. Multiple data points from the same customer were treated as repeated measures. Results A total of 2,393 unique students purchased 6,730 meals. Posters displaying calorie information increased water choice relative to washout periods, while the poster without calorie information (charity only) had no effect. Controlling for fixed effects produced the same results. The calorie message poster influenced less frequent diners more than frequent diners. Conclusions Food-service operations can nudge college students to substitute water for SSBs with a simple calorie-based message to save hundreds of calories per meal.

We study a quantum two-level system under the influence of two independent baths, i.e., a sub-Ohmic pure dephasing bath and an Ohmic or sub-Ohmic relaxational bath. We show that cooling such a system invariably polarizes one of the two baths. A polarized relaxational bath creates an effective asymmetry. This asymmetry can be suppressed by additional dephasing noise. This being less effective, the more dominant low frequencies are in the dephasing noise. A polarized dephasing bath generates a large shift in the coherent oscillation frequency of the two-level system. This frequency shift is little affected by additional relaxational noise nor by the frequency distribution of the dephasing noise itself. As our model reflects a typical situation for superconducting phase qubits, our findings can help optimize cooling protocols for future quantum electronic devices.

We propose a rocking ratchet designed as a symmetric quantum two-state system driven by a single periodic harmonic force and influenced symmetrically by thermal fluctuations. We show that the necessary broken symmetry can dynamically be achieved by a thermal environment that couples to the energy difference between the two states and the tunnel coupling between them. The quantum two-state system is driven by the harmonic periodic drive through its avoided crossing. The correspondingly driven dissipative quantum dynamics results on average in a finite population difference between both states. This then causes directed particle transport.

Environmental noise leads to dephasing and relaxation in a quantum system. Often, a rigorous treatment of multiple noise sources within a system-bath approach is not possible. We discuss the influence of environmental fluctuations on a quantum system whose dynamics is dephasing already due to a phenomenologically treated additional noise source. For this situation, we develop a path-integral approach, which allows us to treat the system-environment coupling in a numerically exact way, and additionally we extend standard perturbative approaches. We observe strong deviations between the numerically exact and the perturbative results even for weak system-bath coupling. This shows that standard perturbative approaches fail for additional, even weak, system-bath couplings if the system dynamics is already dissipative.

A series of N-substituted phthalimides was synthesized by a thermal reaction between N,N′-disubstituted ureas and phthalic acid catalyzed by imidazole in solventless conditions. The products have been obtained in moderate to good yields (53–92%). Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

The call for enhanced financial literacy amongst consumers is a global phenomenon, driven by the growing complexity of financial markets and products, and government concerns about the affordability of supporting an ageing population. Worldwide, defined benefit pensions are giving way to the risk and uncertainty of defined contribution superannuation/pension funds where fund members now make choices and decisions that were once made on their behalf. An important prerequisite for informed financial decision-making is adequate financial knowledge and skills to make competent investment decisions. This paper reports the findings of an online survey of the members of a large Australian public sector-based superannuation fund and shows that although respondents generally understand basic financial matters, on average, their understanding of investments concepts, such as the relationship between risk and returns, is inadequate. These results highlight the need for education programs focusing specifically on developing fund members’ investment knowledge and skills to facilitate informed retirement savings decisions.

Within the context of debate about the state of accounting education in general, introductory accounting subjects have been the target of considerable criticism, particularly in terms of narrow content, technical focus, use of transmissive models of teaching, and inattention to the development of students‟ generic skills. This paper reports on the results of an exploratory study of these issues in introductory accounting and which involved the review of subject outlines and prescribed textbooks, and the conduct of a cross-sectional survey of the introductory accounting teaching coordinators in Australian universities (n=21). The primary aims of the study were to establish and apply benchmarks in evaluating existing curricula with respect to subject orientation, learning objectives, topics, teaching delivery, learning strategies, and assessment. The results of our study suggest that traditional approaches to subject content and delivery continue to dominate, with limited indicators of innovations to enhance the diversity and quality of learning experiences and learning outcomes.

Quantitative measurements of coordination ability were carried out on 76 women with a median age of 37, range 15 to 60. Spacing control, timing control and performance speed were recorded using newly developed computerized equipment, Catsys, presented in this paper. Twenty-three subjects were re-examined 2-3 months after the first measurements. A fair or even high degree of reproducibility of tests was found. Normal values for the entire group and correlation values for the re-examined group are presented. The results from this small study implies that the Catsys may be useful, e.g., in future clinical neurological practice of diagnostics and follow up on patients, in occupational medicine for detection of neurotoxic effects of various neurotoxic substances, in evaluation of drug effects and side effects and for testing people in occupations where normal coordination skills are absolutely necessary.

The following is an account of my first experience as a university tutor in Australia and,in particular, the inspiration I gained from a student whom I shall call Jim. My experience of the 'Jim factor' highlighted the importance of the notion of constructive alignment. I have now learnt that curriculum objectives and assessment tasks must be inter-related with the design of learning and teaching activities. All of these components are important in shaping the learning outcomes experienced by students.

In eukaryotes, mitogen-activated protein kinases (MAPKs) are one of the best studied pathways for posttranslational modification-mediated regulation of protein functions. Here, we describe a rapid in vitro method to screen potential protein phosphorylation sites targeted by MAPKs. The method is based on PCR-mediated mutagenesis together with a type IIs restriction digest. Screening for the successfully mutated clones is further facilitated through introduction of a second diagnostic restriction site. Besides time-saving, this reduces the cost for sequencing confirmation of the positive clones, which are used for subsequent recombinant protein production and kinase assay validation.

We have studied the limits to the switching energy of electrically controlled optical absorption switches. Investigating a case with intraband transitions in asymmetric quantum boxes, it is shown that linear Stark shift allows switch energies of the optical switches that are comparable to the thermal noise limit at 300 K at least up to 30 GHz, provided boxes with very narrow absorption linewidth can be fabricated. This is several orders of magnitude lower energy than required by quadratic Stark shift in a similar, symmetric structure.

A series of N-substituted phthalimides was synthesized by a thermal reaction between N,N′-disubstituted ureas and phthalic acid catalyzed by imidazole in solventless conditions. The products have been obtained in moderate to good yields (53–92%). Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

A comparison of the switch energies of electrically controlled optical absorption switches and electronic switches is performed. It is shown that in the investigated case with quantum box based absorption switches, the switch energies of the optical switches are generally orders of magnitude larger than those of the electronic switches for very high frequencies. Consequences on integration of optical devices as well as on the potential for photonic switching and processing are briefly discussed. >

Tropomyosin is an alpha-helical coiled-coil protein that aligns head-to-tail along the length of the actin filament and regulates its function. The solution structure of the functionally important N terminus of a short 247-residue non-muscle tropomyosin was determined in an engineered chimeric protein, GlyTM1bZip, consisting of the first 19 residues of rat short alpha-tropomyosin and the last 18 residues of the GCN4 leucine zipper. A gene encoding GlyTM1bZip was synthesized, cloned and expressed in Escherichia coli. Triple resonance NMR spectra were analyzed with the program AutoAssign to assign its backbone resonances. Multidimensional nuclear Overhauser effect spectra, X-filtered spectra and (3)J(H(N)-H(alpha)) scalar coupling were analyzed using AutoStructure. This is the first application of this new program to determine the three-dimensional structure of a symmetric homodimer and a structure not previously reported. Residues 7-35 in GlyTM1bZip form a coiled coil, but neither end is helical. Heteronuclear (15)N-(1)H nuclear Overhauser effect data showed that the non-helical N-terminal residues are flexible. The (13)C' chemical shifts of the coiled-coil backbone carbonyl groups in GlyTM1bZip showed a previously unreported periodicity, where resonances arising from residues at the coiled-coil interface in a and d positions of the heptad repeat were displaced relatively upfield and those arising from residues in c positions were displaced relatively downfield. Heteronuclear single quantum coherence spectra, collected as a function of temperature, showed that cross-peaks arising from the alpha-helical backbone and side-chains at the coiled-coil interface broadened or shifted with T(M) values approximately 20 degrees C lower than the loss of alpha-helix measured by circular dichroism, suggesting the presence of a folding intermediate. The side-chain of Ile14, a residue essential for binding interactions, exhibited multiple conformations. The conformational flexibility of the N termini of short tropomyosins may be important for their binding specificity.

A study was undertaken in Nijmegen, in the Netherlands, to compare the attendance rate following a call system for cervical cancer screening organized by general practitioners, with the attendance rate resulting from the Dutch national call system. Women are invited for screening on a three yearly basis and in 1990 1616 women were identified by nine practices as being in the appropriate age group (35 to 54 years) to attend for cervical cancer screening while 10,387 women were identified by the national call system. The attendance rate among the 1101 women in the rural general practices was 58%, compared with 49% of 4154 women in the matched group receiving an invitation from the national call system. The attendance rate among the 515 women in the urban general practices was 55%, compared with 41% of 6233 women in the matched group receiving an invitation from the national call system. Invitations from general practitioners resulted in similar percentages of women in all age groups attending for screening. Four general practices sent a reminder letter or made a telephone call to non-attenders. A reminder increased the attendance rate from 58% to 70%. It is concluded that a general practice based call system for cervical screening produces a higher attendance rate than the national call system.

Thus far, the response to the nationwide screening programme for cervical cancer in The Netherlands, which was started in 1989, has been disappointing. One way to improve response is to involve general practitioners in the call system. A postal survey was conducted to review the implementation of the current screening programme in general practice and to examine the willingness of general practitioners to participate in a general practice-based call system. The response rate to the survey was 90%. The general practitioners were dissatisfied with follow-up, cost and time spent and compliance of women. Of all respondents 60% had already set up a call system within the practice or were willing to do so; another 31% were willing to participate in a regionally organized practice-based call system. On the basis of the results of this study a centralized general practice-based call system is recommended. The next step is to study the applicability of this system in a pilot programme.

Since 1975 the general practitioners of 'Ons Medies Centrum' in Oss have been inviting women systematically for cervical screening and cervical smears. The attendance and protection rate were evaluated for the period 1975-1989. 85% of the women 35-54 years of age had had a cervical smear within 5 years after they entered the general practice or had not been invited because of a total hysterectomy. After a starting period of a few years the protection rate stabilised at 75%. There was no relation between residential quarter, health insurance, ethnic origin and attendance for the screening. Age was the only factor related to attendance: the attendance rate among older women was lower.

Quantitative measurements of coordination ability and performance speed were carried out on 76 female day-case patients undergoing minor gynaecological operations. The women were assigned at random to the anaesthetic agent used, propofol 2.5 mg/kg or thiopentone 4 mg/kg. Spacing control, timing control and performance speed were recorded using a newly developed computerized coordination ability test system. The patients were tested once before the operation and 0.5, 1 and 2 h after awakening. Postoperatively the initial impairment and the subsequent regression towards preoperative test results were very similar whether the anaesthetic agent was propofol or thiopentone. Although the test apparatus was able to detect even minor differences, no postoperative test showed statistically significant differences between the two groups. We find it reasonable to conclude that there is no difference in recovery of coordination ability following propofol- or thiopentone-induced anaesthesia.

Strain-gauge plethysmography was used to determine the systolic arterial pressure in the great toe of 38 patients (aged 23–70 yr) undergoing lung surgery. In eight patients (21%) manual compression of the dorsalis pedis artery reduced the arterial pressure in the great toe to less than 40 mm Hg, and cannulation of the artery was not attempted. In 24 of 30 patients with adequate collateral arterial supply, a Teflon cannula (Venflon 1.20) was inserted percutaneously to the dorsalis pedis artery. Median cannulation time was 160 min. Six patients (25%, 95% confidence limits 10–47%) developed thrombosis of the artery and, in one, unsuccessful cannulation caused thrombosis. In two patients, recanalization of the artery occurred between the 2nd and the 8th day after operation. In four patients, examination 3–5 months after cannulation revealed a persisting decrease in the function of the dorsalis pedis artery. This suggests that the dorsalis pedis artery should not normally be selected for cannulation.

Summary. Blood flow and filtration of water across the vascular bed in human forearm muscles were studied at rest and during graded exercise with a hand ergometer. Blood flow was measured by dye dilution and water filtration was determined after injection of hyperoncotic albumin solution (23%) in the brachial artery creating a tissue to blood ultrafiltration measurable as a dilution in the effluent blood. The filtration constants were expressed as a filtration coefficient Fe (ml water/ml plasma mmHg increase in oncotic pressure), and, multiplying by the plasma flow, as a filtration capacity Kf (ml water/100 ml tissue min mmHg increase in oncotic pressure). During the increase in plasma flow induced by exercise, Fe remained constant at about 0·0007, but Kf increased in parallel with the hyperaemia from 0·0031 to 0·038 when plasma flow increased from 4 to 48 ml (100 ml min)-1. The data suggest a more massive recruitment of exchange area during exercise (a factor 12) than suspected on the basis of ultrafiltration in animals made with the prolonged venous stasis technique (showing a factor 2–5). The estimated variability in exchange surface area indicates, that animal studies of muscle circulation, whether pertaining to capillary permeability or capillary filtration should gain by an independent estimate of the number of capillaries that are flowing during the particular experimental situation.

Arterial pressure was measured simultaneously in the thumb and in the contralateral arm using strain-gauge plethysmography in 100 healthy persons aged 13--43 yr, before and after compression of the radial or the ulnar artery. The radial and ulnar pulses were palpable in all instances. In 29 (14.5%) hands compression of either artery did not reduce the thumb pressure. In 152 (76%) occlusion of the radial artery caused a decrease of more than 10 mm Hg, but never to less than 40 mm Hg. In 91 (45.5%) occlusion of the ulnar artery reduced thumb pressure, on three occasions to less than 40 mm Hg. Radial dominance was shown in 110 hands (55.0%), 24 (12.0%) showed ulnar dominance and in 66 (33.0%) neither vessel dominated.

A computer-controlled microdensitometer has been designed and built in this laboratory for measuring Guinier powder diffraction photographs. It consists of a microcomputer-controlled single-beam microdensitometer using as a measuring unit an IR emitting diode ( lambda =940 nm), a collimator system and a photodiode. The scan process is controlled by a microcomputer, Zilog MCZ 1/05, with two floppy disc units. The microcomputer is also used for data reduction. A direct connection with a large scale computer, Amdahl 470/V7, makes it possible to run indexing, search-match or profile refinement programs within 15 minutes from the moment the film is mounted in the scanner.

Systolic arterial pressure in the thumb was measured using strain-gauge plethysmography before and after compression of the radial artery in 259 patients (aged 11--75 years), undergoing vascular or open-heart surgery. In 38 hands (in 27 patients aged 37--75 years), manual compression of the radial artery reduced the arterial pressure in thumb to less than 40 mmHg (5.3 kPa), and consequently the collateral ulnar arterial supply was judged to be inadequate. Because 27 out of 259 patients (10.4%) would be without adequate blood supply to one or both thumbs following occlusion of the radial arteries, cannulation of the radial artery should be performed only after ensuring the presence of an adequate collateral ulnar arterial supply.

Three experiments on lateralization of electrodermal orienting and conditioned behavior are reported. The basic findings show effects of hemispheric asymmetry on initial magnitude and rate of habituation of phasic stimulus-elicited electrodermal responses. In summary, responses to verbal stimuli repeatedly flashed to the right visual half-field are larger than corresponding responses in the left half-field. Similarily, spatially relevant stimuli initially presented to the left half-field result in larger responses than when the same stimuli are repeatedly presented in the right half-field. In the auditory modality, data show asymmetrical control of responding to verbal material in a dichotic conditioning paradigm with greater resistance to extinction when the conditioned stimulus is initially fed only to the left hemisphere as compared to when it is fed only to the right hemisphere. It is argued that the present approach taps on basic mechanisms for the lateralization of attentional and associative functions.

Reports of sudden death of patients during i.v. administration of methylprednisolone (M.P.) prompted the present study of the hemodynamic effect of M.P. given i.v. to dogs. Fifteen healthy, mongrel dogs were anesthetized with thiomebumal, fentanyl, droperidol, pancuronium and N2O/O2. With ventilation and circulation in steady state, M.P. 30 mg/kg b.w. was given i.v. either as a push bolus (n=7) or over a 5-min period (n=8). In the bolus group, mean aortic pressure (MAP) and systemic vascular resistance (SVR) had decreased to 72 and 60%, respectively, 1 min after the start of the steroid injection, while heart rate (HR), cardiac index (CI), mean pulmonary arterial pressure (MPAP) and left ventricular work (LVW) had not changed significantly. In the 5-min group, the HR increased by 23%, while the other parameters were unchanged during the injection period. Within 5 min after the termination of the steroid injection all hemodynamic parameters had returned to pre-injection levels in both groups. Sodium, potassium, magnesium, protein and calcium in serum were unchanged in both groups during the injection period and in the following 15 min. A significant, transient fall in ionized calcium was observed in all six dogs in which this ion was measured. It was concluded that rapid i.v. injection of pharmacological doses of M.P. in hemodynamically stable, anesthetized dogs causes immediate, transient decreases in SVR and MAP. The mechanisms may be an alpha adrenergic blocking action or a direct effect on the muscles in the peripheral vessels, combined with a negative inotropic effect on the myocardium, possibly mediated through an impeded calcium release.

Summary. Water filtration in the human forearm was determined with a new method using a hyperoncotic transient of albumin solution infused into the brachial artery. Baseline dilution of labelled albumin in deep forearm vein plasma in excess of the contribution from arterial blood and from infusate was assumed to originate from extravascular water filtered into the blood by the transient. The filtration coefficient (Fe) was determined as the ratio between filtered water and increase in colloid osmotic pressure in the blood samples, and gives the filtrative water permeability in the exchange areas of the microcirculation. In 10 normal volunteers, Fe was 0·00082 ml (ml mmHg)-1 (SD = 0·00007). Multiplication of Fe by plasma flow in the forearm gave a filtration capacity (Kf) of 0·0036 ml (100 ml tissue min mmHg)-1 (SD=0·00137). This filtration capacity (Kf) represents that of fast flowing regions in the forearm muscles, but it is of the same order of magnitude as the capillary filtration coefficient (CFC) determined plethysmographically for the entire forearm by the venous stasis technique.