bluuebunny/crossref_metadata_2025 huggingface dataset:
Fertility Decline in Paraguay
Authors: Ishida Kanako , Stupp Paul , Melian Mercedes
Published: August 2009

Recent reproductive health surveys show that the fertility rate in Paraguay decreased precipitously from 4.3 lifetime births per woman in 1995–98 to 2.9 births in 2001–04. In this study, we establish data consistency between the 1998 and 2004 surveys by comparing a series of cohort‐specific period rates and use the Bongaarts framework of proximate determinants of fertility to demonstrate that an increase in the contraceptive prevalence rate (CPR) between 1998 and 2004 fully accounts for the fertility decline. Decomposition of rates shows that changes in group‐specific CPRs explain a greater proportion of the change in the overall CPR than do changes in population composition by educational attainment, urban residence, region, and language spoken at home. Finally, we show that younger cohorts of women in 2004 reported ideal completed fertility desires of less than 2.9 births, suggesting that the fertility rate is likely to continue to decrease.
Carbon Sequestration in Two Alpine Soils on the Tibetan Plateau
Authors: Tian Yu‐Qiang , Xu Xing‐Liang , Song Ming‐Hua , Zhou Cai‐Ping , Gao Qiong , Ouyang Hua
Published: August 2009

Soil carbon sequestration was estimated in a conifer forest and an alpine meadow on the Tibetan Plateau using a carbon‐14 radioactive label provided by thermonuclear weapon tests (known as bomb‐14C). Soil organic matter was physically separated into light and heavy fractions. The concentration spike of bomb‐14C occurred at a soil depth of 4 cm in both the forest soil and the alpine meadow soil. Based on the depth of the bomb‐14C spike, the carbon sequestration rate was determined to be 38.5 g C/m2 per year for the forest soil and 27.1 g C/m2 per year for the alpine meadow soil. Considering that more than 60% of soil organic carbon (SOC) is stored in the heavy fraction and the large area of alpine forests and meadows on the Tibetan Plateau, these alpine ecosystems might partially contribute to “the missing carbon sink”.
Can ice survive in main-belt comets? Long-term evolution models of comet 133P/Elst-Pizarro
Authors: Prialnik Dina , Rosenberg Eric D.
Published: August 2009

We present detailed evolutionary calculations spanning 4.6 × 109 yr for a model representing main-belt comet 133P/Elst-Pizarro, considering different initial compositions: mixtures of ices and dust. We find that only crystalline H2O ice may survive in the interior of the nucleus, and may be found at depths ranging from ∼50 to 150 m. Other volatiles will be completely lost. We further show, by means of fully three-dimensional evolutionary calculations, that if the ice is exposed, say as a result of a collision, the resulting activity is similar to the observed pattern of the behaviour of the comet for a large spin axis inclination, even if only a patch of ice is exposed.
Altruism and Self Interest in Medical Decision Making
Authors: Rubin Paul H.
Published: August 2009

It is not from the benevolence of the butcher, the brewer, or the baker that we expect our dinner, but from their regard to their own interest.

Adam Smith, Wealth of Nations

As the quote above indicates, economists generally are more comfortable with self interest as a motivating force for social benefit than with altruism. This is because in most instances in a market economy, self interest will lead agents to provide benefits for others. Ultimately this is because the butcher or baker will not get paid unless he does something that others are willing to pay for. This is the source of the famous “invisible hand,” also discussed by Adam Smith.

This might sound trivial, except that in discussing aspects of medicine we seem to lose sight of this mechanism and rely on other tools to provide benefits. These tools do not work as well as naked self interest would. Some might say that medicine and medical progress is too important to depend on the market.
Drug Reps Off Campus! Promoting Professional Purity by Suppressing Commercial Speech
Authors: Stell Lance K.
Published: August 2009

In purity and holiness I will guard my life and my art.

Every physician-patient encounter is a conflict of interest. Every physician-payer encounter is also a conflict of interest.

Wide-spread criticism of the pharmaceutical industry’s extravagant marketing practices and some doctors’ undignified, even appalling eagerness to stuff themselves, their pockets and their offices with the industry’s “stuff,” prompted physician groups, the drug and device industry itself (albeit synergized by the federal government’s ominous shadow) to institute reforms designed better to limit industry influence on physicians.

But according to Troyen Brennan and his coauthors, the reforms, while reducing some of the most egregious instances of industry influence peddling and physicians’ self-debasement, were doomed fundamentally, for three reasons. First, they were based on common sense but incorrect assumptions about the mechanism of industry influence and on myths about the efficacy of disclosure as an ethical disinfectant. Second, they relied on voluntary adherence and so failed to pinpoint responsibility for monitoring compliance and enforcement.
DTC Advertising Harms Patients and Should Be Tightly Regulated
Authors: Lurie Peter
Published: August 2009

Like all interventions in health care, direct-to-consumer (DTC) advertising should be evaluated by comparing its risks to its benefits, in the context of the available or potentially available alternatives. The objective, of course, is to realize any unique benefits while minimizing the risks. On balance, the adverse effects of DTC advertising outweigh the still-undemonstrated benefits of the advertising.

DTC advertising must be seen in the context of overall pharmaceutical company expenditures on advertising. In 2005, the industry spent $29.9 billion dollars on promotions (up from $11.4 billion in 1996), of which a relatively small fraction, $4.2 billion (14.2%), was spent on DTC advertising. The percentage spent on DTC advertising has been relatively constant this decade. Promotions to professionals (24.2%) and samples (61.8%) accounted for far larger percentages of total promotional spending in 2005.
The Ethical Health Lawyer: An Empirical Assessment of Moral Decision Making
Authors: Perry Joshua E. , Moore Ilene N. , Barry Bruce , Clayton Ellen Wright , Carrico Amanda R.
Published: August 2009

The empirical literature exploring lawyers and their moral decision making is limited despite the “crisis” of unethical and unprofessional behavior in the bar that has been well documented for over a decade. In particular we are unaware of any empirical studies that investigate the moral landscape of the health lawyer’s practice. In an effort to address this gap in the literature, an interdisciplinary team of researchers at Vanderbilt University designed an empirical study to gather preliminary evidence regarding the moral reasoning of health care attorneys. The primary research question was how health lawyers respond when they encounter ethical or moral dilemmas in their practice for which the law fails to offer a bright-line solution. In exploring this question, we sought to understand better what motivations or influences guide action when health lawyers confront ethical quandaries, and whether there are specific differences, e.g., gender, experience, or religiosity, that are associated with specific responses to situations testing ethical or moral boundaries.
Tax Credits for Health Insurance
Authors: Goldberg Fred T. , Camic Susannah
Published: August 2009

This Legal Solutions in Health Reform paper discusses the role that tax law can play in the implementation of health reform. The tax code has served as the primary vehicle for subsidizing health care in the U.S. for most of the last century and will likely play a role in any future reform efforts. However, the interplay between tax law and health policy presents a series of critical design and implementation challenges with which any health care reform package — be they liberal or conservative — must grapple. This paper considers some of the most pressing of these issues. While it does not prescribe a particular outcome, it will attempt to identify potential tax solutions that might receive broad support and to observe the policy and administrative design questions that any discussion of these solutions should take into account.
Classical Mindfulness
Authors: Rapgay Lobsang , Bystrisky Alexander
Published: August 2009

Among the modern versions of mindfulness, mindfulness based stress reduction (MBSR) has played the key role in introducing mindfulness practice to the field of psychology and medicine. In fact, the efforts to integrate mindfulness into psychology have resulted in further adaptation of MBSR into more secular and psychological forms as well as the creation of a number of mindfulness measures such as the Mindful Attention Awareness Scale, the Freiburg Mindfulness Inventory, the Kentucky Inventory of Mindfulness Skills, and the Cognitive and Affective Mindfulness Scale. At the same time there is increasing scrutiny of mindfulness that goes beyond the initial positive efficacy studies resulting in several important questions being raised. These range from the absence of an operational definition of mindfulness as well as little evidence for the mechanisms of mindfulness that account for outcome changes for various psychopathology and medical conditions. Questions about the defining characteristics of mindfulness are also being raised such as the lack of differentiation between the features called attention and awareness and the interchangeable use of the two terms in modern descriptions of mindfulness. Such questions resonate with traditional practitioners of Buddhist contemplative psychology for whom attention signifies an every‐changing factor of consciousness, while awareness refers to a stable and specific state of consciousness.
Regeneration and Repair
Authors: Friedman Rachel S. C. , Krause Diane S.
Published: August 2009

When it comes to the capacity to regenerate damaged parts of the body, humans are by no means the most advanced among animal species. At the level of single cell populations, humans do exhibit some degree of regenerative potential‐‐for example, hepatocytes have the ability to restore up to 75% of a surgically removed or damaged liver. However, as every schoolchild knows, salamanders and starfish can regrow entire amputated appendages, a remarkable feat well beyond the scope of human capacity. Accordingly, the standing consensus position of the scientific community has deemed mammals fundamentally and unalterably different from those more “primitive” yet regeneration‐competent species.1 Current approaches for the restoration of organ function in humans have therefore been limited to allogeneic organ or cell transplantation—strategies that, while effective, nonetheless exhibit major limitations based on availability of donor tissues and the risk of rejection unless extensive immunosuppression is induced.
Can Meditation Slow Rate of Cellular Aging? Cognitive Stress, Mindfulness, and Telomeres
Authors: Epel Elissa , Daubenmier Jennifer , Moskowitz Judith Tedlie , Folkman Susan , Blackburn Elizabeth
Published: August 2009

Understanding the malleable determinants of cellular aging is critical to understanding human longevity. Telomeres may provide a pathway for exploring this question. Telomeres are the protective caps at the ends of chromosomes. The length of telomeres offers insight into mitotic cell and possibly organismal longevity. Telomere length has now been linked to chronic stress exposure and depression. This raises the question of mechanism: How might cellular aging be modulated by psychological functioning? We consider two psychological processes or states that are in opposition to one another–threat cognition and mindfulness–and their effects on cellular aging. Psychological stress cognitions, particularly appraisals of threat and ruminative thoughts, can lead to prolonged states of reactivity. In contrast, mindfulness meditation techniques appear to shift cognitive appraisals from threat to challenge, decrease ruminative thought, and reduce stress arousal. Mindfulness may also directly increase positive arousal states. We review data linking telomere length to cognitive stress and stress arousal and present new data linking cognitive appraisal to telomere length. Given the pattern of associations revealed so far, we propose that some forms of meditation may have salutary effects on telomere length by reducing cognitive stress and stress arousal and increasing positive states of mind and hormonal factors that may promote telomere maintenance. Aspects of this model are currently being tested in ongoing trials of mindfulness meditation.
Positive Affects and the Transformation of Suffering into Flourishing
Authors: Fosha Diana
Published: August 2009

Three investigative realms with widely divergent methodologies arrive at uncannily similar conclusions about the vital role of positive affective phenomena in optimal adaptation, resilience, affect regulation, cardiac health, and subjective well‐being: research on resilience and human flourishing; Indo‐Tibetan practices and the emergent yogic sciences; and the practice of AEDP (Accelerated Experiential Dynamic Psychotherapy), a healing‐oriented, transformation‐based model of psychotherapy. AEDP has explored the vital role of positive emotions in the process of change in general, and, more specifically, in therapeutic work with painful and overwhelming emotional experience, and has identified and descried a phenomenology of positive affective experiences, including the healing affects, and core state, which signal the operation of healing transformational processes. This chapter focuses on how, in the course of one therapeutic hour – through the moment‐to‐moment tracking of bodily rooted experience and dyadic affect regulation in the context of a relationship in which the individual feels safe and known – the processing of suffering, i.e., stress‐based, traumatizing, painful emotional experiences naturally culminates in flourishing, i.e., deeply positive experiences of aliveness, hope, faith, clarity, agency, simplicity, compassion, joy, and truth. Key to this is the focus on and experiential processing of the experience of healing transformation. Thus, there unfolds a series of cascading transformations, with each transition somatically marked by positive transformational affects, until we arrive at core state, a state characterized by the positive affective phenomena that underlie some of our highest strivings and deepest joys.
Bioelectromagnetic and Subtle Energy Medicine
Authors: Rosch Paul J.
Published: August 2009

The concept of a “life energy” can be found in many cultures in the present time, as well as in past eras reaching back to the ancients. Variously called qi (chi), ki, the “four humors,”prana, “archaeus,”“cosmic aether,”“universal fluid,”“animal magnetism,” and “odic force,” among other names, this purported biofield is beginning to yield its properties and interactions to the scientific method. Subtle energy is the term used in this chapter, which traces the recent history of subtle energy studies from Harold Saxton Burr and Björn Nordenström to Jim Oschman and Jacques Benveniste. This work takes signaling in living systems from the chemical/molecular to the physical/atomic level of communication. Effects on heart rate variability, stress response, inflammation, and the vagus nerve have been demonstrated and raise the question ‐ Can the power of subtle energies be harnessed for health enhancement? It is fully accepted that good health depends on good communication both within the organism and between the organism and its environment. Sophisticated imaging procedures brought to bear on telomere, stem cell, and genetic research are confirming the ability of meditation and some other traditional practices to promote optimal health through stress reduction.
Lifetime history of substance misuse in first‐episode psychosis: prevalence and its influence on psychopathology and onset of psychotic symptoms
Authors: Kamali Moayyad , McTigue Orfhlaith , Whitty Peter , Gervin Maurice , Clarke Mary , Browne Stephen , Larkin Conall , O'Callaghan Eadbhard
Published: August 2009

Introduction: Substance misuse (SM) (drug/alcohol dependence or abuse) in psychotic illness is an increasingly recognized problem. We aimed to estimate the prevalence and examine the influence of SM on age at onset of psychosis and psychopathology among patients with first‐episode psychosis.

Method: One hundred seventy‐one consecutive patients with first‐episode psychosis were assessed. SM, age of onset of psychosis and psychopathology were determined using valid instruments.

Results: Seventy‐seven (46%) patients had a lifetime history of SM and were predominately males, had more positive symptoms, and in the majority of cases (84%), started misusing substances before the onset of psychosis (SM‐BP). There was no difference in age of onset between patients with SM‐BP and the rest of the sample.

Conclusion: Lifetime history of SM is common and may influence psychopathology, but does not appear to influence or bring forward the age at onset of psychotic symptoms.
Engagement and early termination of contact with a community‐based early intervention service for personality disorder in young adults
Authors: Farrand Paul , Booth Nicholas , Gilbert Tony , Lankshear Gloria
Published: August 2009

Background: Few studies have examined factors associated with continuity of care in a community‐based early intervention service for personality disorder in patients aged 16–25.

Aims: To estimate the probability of dropping out of care in patients attending an early intervention service for personality disorder and identify patient characteristics associated with those who drop out, are discharged or continue using the service.

Method: A 24‐month cohort of first‐contact patients attending the early intervention service was followed up for 12 months to identify drop‐outs, discharges and those still using the service.

Results: One hundred eighty‐three first contact patients were referred/self‐referred during the study timescale. After 12‐month follow‐up, 83 (45%) were discharged, 39 (21%) still using the service and 61 (33%) dropped out. Drop out was most likely among patients aged 21–25, from higher socio‐economic groups and highest during months 3–5 of service use. No discharges occurred until at least 3 months into the service, with a peak at 6–8 months.

Conclusions: Although sharing many factors predicting increased levels of drop‐out, the rate of drop‐out among young adults aged between 16–25 attending an early intervention service for personality disorder was equivalent to that experienced by services for adults with a long history of personality disorder diagnosis. Concerns exist, however, concerning increased rates of drop‐out among patients reporting a greater number of difficulties, reporting a common mental health or substance abuse problem, and during months 3–5 of service use. Implications of the results for future service developments are discussed.
The Role of Climate and Human Influences in the Dry‐Up of the Jinci Springs, China1
Authors: Hao Yonghong , Zhu Yuen , Zhao Ying , Wang Wei , Du Xin , Yeh Tian‐Chyi J.
Published: August 2009

Abstract:  One of the largest karst springs in North China, the Jinci Springs, dried up and has remained dry since 1994. We develop a correlation analysis with time‐lag and a regression analysis with time‐lag to study the relation between spring flow and precipitation. This allows us to obtain a better understanding of karst hydrological processes by differentiating the contribution of variation in precipitation from anthropogenic impacts on the dry‐up of Jinci Springs. We divided the karstic hydrological processes into two phases: pre‐1961 and post‐1961. In the first phase (i.e., 1954‐1960) the groundwater recharge was affected by precipitation alone, and in the second phase (i.e., 1961‐1994) the groundwater recharge was influenced by both precipitation and human activities. Using precipitation and groundwater recharge data in the first phase, we set up a groundwater recharge model with time‐lags. By running the time‐lags model, we acquired the groundwater recharge likely to occur under the sole effect of precipitation in the second phase. Using a water‐balance calculation, we conclude that the groundwater recharge exhibited statistical stationarity, and the Jinci Springs dry‐up was the result of anthropogenic activities. At least three specific types of anthropogenic activities contributed to the drying‐up of Jinci Springs: (1) groundwater pumping accounts for 51%, (2) the dewatering from coal mining accounts for 33%, (3) and dam‐building 14%. The drying‐up of Jinci Springs meant that the groundwater drained from the aquifer’s fractures, and subsequently changed the structure of the karst aquifer. Although groundwater exploitation has been reduced, the flow at Jinci Springs has not reoccurred.
Science and Decision Making: Water Management and Tree‐Ring Data in the Western United States1
Authors: Rice Jennifer L. , Woodhouse Connie A. , Lukas Jeffrey J.
Published: August 2009

Abstract:  Growing populations, limited resources, and sustained drought are placing increased pressure on already over‐allocated water supplies in the western United States, prompting some water managers to seek out and utilize new forms of climate data in their planning efforts. One source of information that is now being considered by water resource management is extended hydrologic records from tree‐ring data. Scientists with the Western Water Assessment (WWA) have been providing reconstructions of streamflow (i.e., paleoclimate data) to water managers in Colorado and other western states (Arizona, New Mexico, and Wyoming), and presenting technical workshops explaining the applications of tree‐ring data for water management for the past eight years. Little is known, however, about what has resulted from these engagements between scientists and water managers. Using in‐depth interviews and a survey questionnaire, we attempt to address this lack of information by examining the outcomes of the interactions between WWA scientists and western water managers to better understand how paleoclimate data has been translated to water resource management. This assessment includes an analysis of what prompts water managers to seek out tree‐ring data, how paleoclimate data are utilized by water managers in both quantitative and qualitative ways, and how tree‐ring data are interpreted in the context of organization mandates and histories. We situate this study within a framework that examines the coproduction of science and policy, where scientists and resource managers collectively define and examine research and planning needs, the activities of which are embedded within wider social and political contexts. These findings have broader applications for understanding science‐policy interactions related to climate and climate change in resource management, and point to the potential benefits of reflexive interactions of scientists and decision makers.
Processing Instruction and Dictogloss: A Study on Object Pronouns and Word Order in Spanish
Authors: VanPatten Bill , Inclezan Daniela , Salazar Hilda , Farley Andrew P.
Published: August 2009

Abstract: In the current study, we present the findings of an experiment with 108 participants of Spanish as a second language in which we compared the effects of dictogloss (DG) and processing instruction (PI) and compared both sets of effects to a control group. Our findings do not support the results of a recent study, Qin (2008). In that study, DG and PI were found to be equally effective; however, we find that PI is superior overall to DG as an instructional intervention, a finding much more in line with the original research on which Qin based her study (e.g., VanPatten & Cadierno, 1993). We trace differences in results to materials and assessment tasks in Qin's study, which departed significantly from previous research.
Strain Uniformity in Biaxial Specimens is Highly Sensitive to Attachment Details
Authors: Eilaghi Armin , Flanagan John G. , Brodland G. Wayne , Ethier C. Ross
Published: August 2009

Biaxial testing has been used widely to characterize the mechanical properties of soft tissues and other flexible materials, but fundamental issues related to specimen design and attachment have remained. Finite element models and experiments were used to investigate how specimen geometry and attachment details affect uniformity of the strain field inside the attachment points. The computational studies confirm that increasing the number of attachment points increases the size of the area that experiences sensibly uniform strain (defined here as the central sample region where the ratio of principal strains E11/E22<1.10), and that the strains experienced in this region are less than nominal strains based on attachment point movement. Uniformity of the strain field improves substantially when the attachment points span a wide zone along each edge. Subtle irregularities in attachment point positioning can significantly degrade strain field uniformity. In contrast, details of the apron, the region outside of the attachment points, have little effect on the interior strain field. When nonlinear properties consistent with those found in human sclera are used, similar results are found. Experiments were conducted on 6×6 mm talc-sprinkled rubber specimens loaded using wire “rakes.” Points on a grid having 12×12 bays were tracked, and a detailed strain map was constructed. A finite element model based on the actual geometry of an experiment having an off-pattern rake tine gave strain patterns that matched to within 4.4%. Finally, simulations using nonequibiaxial strains indicated that the strain field uniformity was more sensitive to sample attachment details for the nonequibiaxial case as compared to the equibiaxial case. Specimen design and attachment were found to significantly affect the uniformity of the strain field produced in biaxial tests. Practical guidelines were offered for design and mounting of biaxial test specimens. The issues addressed here are particularly relevant as specimens become smaller in size.
Nonlinear large deflection of nanopillars fabricated by focused ion-beam induced chemical vapor deposition using double-cantilever testing
Authors: Tanaka Hiro , Shinkai Masaki , Shibutani Yoji , Kogo Yasuo
Published: August 2009

Nanopillars with nanosized diameter and microsized length can be constructed by chemical vapor deposition using a focused ion beam. For a pillar consisting of an outer amorphous carbon ring and an inner gallium core, we performed the bending tests using the unique double-cantilever specimen joining two pillars together by an electron-beam deposition technique in a scanning electron microscope. The precise load-deflection curves indicate that the pillars have a nonlinear softening region after the linear response as the diameter increases. However, pillars finally become extremely hardened at the large deformation. Thus, the pillar intrinsically possesses much more flexibility and stable deflection for bending than expected, in contrast to tensile deformation. The bending rigidity obtained by the infinitesimal deflection corresponds well to that by the resonance vibration tests reported so far. It also certifies that the proposed double-cantilever bending method can maintain high accuracy for the nanoscaled materials testing.
Effects of tertiary MLC configuration on secondary neutron spectra from 18 MV x‐ray beams for the Varian 21EX linear accelerator
Authors: Howell Rebecca M. , Kry Stephen F. , Burgett Eric , Followill David , Hertel Nolan E.
Published: August 2009

The effect of the jaw configuration and the presence and configuration of the tertiary multileaf collimator (MLC) on the secondary neutron spectra for an 18 MV Varian 21EX linear accelerator (linac) is investigated in detail. The authors report the measured spectra for four collimator (jaw‐and‐MLC) configurations. These configurations represent the extreme settings of the jaws and MLC and should therefore describe the range of possible fluence and spectra that may be encountered during use of this linac. In addition to measurements, a Monte Carlo model was used to simulate the four collimator configurations and calculate the energy spectra and fluence at the same location as it was measured. The Monte Carlo model was also used to calculate the sources of neutron production in the linac head for each collimator configuration. They found that photoneutron production in the linac treatment head is dominated by the order in which the primary photon beam intercepts the high‐ material. The primary collimator, which has the highest position in the linac head (in a fixed location), is the largest source of secondary neutrons. Thereafter, the collimator configuration plays a role in where the neutrons originate. For instance, if the jaws are closed, they intercept the beam and contribute substantially to the secondary neutron production. Conversely, if the jaws are open, the MLC plays a larger role in neutron production (assuming, of course, that it intercepts the beam). They found that different collimator configurations make up to a factor of 2 difference in the ambient dose equivalent.
4D in‐beam positron emission tomography for verification of motion‐compensated ion beam therapy
Authors: Parodi Katia , Saito Nami , Chaudhri Naved , Richter Christian , Durante Marco , Enghardt Wolfgang , Rietzel Eike , Bert Christoph
Published: August 2009

Purpose:

Clinically safe and effective treatment of intrafractionally moving targets with scanned ion beams requires dedicated delivery techniques such as beam tracking. Apart from treatment delivery, also appropriate methods for validation of the actual tumor irradiation are highly desirable. In this contribution the feasibility of four‐dimensionally (space and time) resolved, motion‐compensated in‐beam positron emission tomography (4DibPET) was addressed in experimental studies with scanned carbon ion beams.

Methods:

A polymethyl methracrylate block sinusoidally moving left‐right in beam's eye view was used as target. Radiological depth changes were introduced by placing a stationary ramp‐shaped absorber proximal of the moving target. Treatment delivery was compensated for motion by beam tracking. Time‐resolved, motion‐correlated in‐beam PET data acquisition was performed during beam delivery with tracking the moving target and prolonged after beam delivery first with the activated target still in motion and, finally, with the target at rest. Motion‐compensated 4DibPET imaging was implemented and the results were compared to a stationary reference irradiation of the same treatment field. Data were used to determine feasibility of 4DibPET but also to evaluate offline in comparison to in‐beam PET acquisition.

Results:

4D in‐beam as well as offline PET imaging was found to be feasible and offers the possibility to verify the correct functioning of beam tracking. Motion compensation of the imaged ‐activity distribution allows recovery of the volumetric extension of the delivered field for direct comparison with the reference stationary condition. Observed differences in terms of lateral field extension and penumbra in the direction of motion were typically less than 1 mm for both imaging strategies in comparison to the corresponding reference distributions. However, in‐beam imaging retained a better spatial correlation of the measured activity with the delivered dose.

Conclusions:

4DibPET is a feasible and promising method to validate treatment delivery of scanned ion beams to moving targets. Further investigations will focus on more complex geometries and treatment planning studies with clinical data.
Stable layers of oxyethylated alcohols adsorbed on the surface of a hanging mercury drop electrode under tensammetric conditions
Authors: Pawlak M. Krystyna
Published: August 2009

The stability of adsorbed layers on a hanging mercury drop electrode was examined for oxyethylated alcohols ( 18-14, 18-10, 18-6, 10-14 and 6-14 where the first number denotes the number of carbon atoms in the n-alkyl chain and the second, the number of oxyethylene sub-units), Triton X-100 and for 18-14/10-14 and 18-14/Trriton X-100 mixtures. The film stability was assessed in terms of the number of repetitions of the tensammetric peak recorded at the mercury drop after 5 or 10 min of adsorptive preconcentration. The most stable film is formed by the polyoxyethyleneoctadecyl monoethers, both alone and in the mixtures studied. The films are broken down by vigorous stirring of the solution for a certain time applying an electrode potential above the adsorption range of the surfactants.
Effect of Triton X-100 on the electrochemical reduction of N-methylnicotinic acid at a mercury electrode
Authors: Pérez Rafael , Rodriguez-Amaro Rafael , Avila José L. , Camacho Luis , Ruiz Juan J.
Published: August 2009

Reaction mechanism for pH ranges below and above 7.5 has been formulated. Theoretical i-E-c-t relationship has been proposed and discussed on the basis of the experimental results.
Stripping voltammetry of zinc/polyacrylate complexes: Influence of molar mass
Authors: Van den Hoop Marc A. G. T. , Leus Francisco M. R. , Van Leeuwen Herman P.
Published: August 2009

Differential pulse anodic stripping voltammetry (DPASV) has been applied to complex systems of zinc(II) and polyacrylic acid (PAA) for various molar masses of the polyacid. The Zn/PAA complex is voltammetrically labile over the whole range of metal-to-ligand ratios. Analysis of the data in terms of a mean diffusion coefficient, which decreases with increasing molecular mass, yields a consistent picture with molar mass-independent complex stabilities. The speciation of Zn(II) in such a polyelectrolyte system varies with the concentration of carboxylate groups and with the overall charge of the PAA, but it is invariant with the polyionic molar mass.
Transfer of trispolypyridineruthenium(II) chelates in their ground and excited states across the water/1,2-dichloroethane interface
Authors: Hanzlík Josef , Camus Anna Maria
Published: August 2009

Transfer of trispolypyridineruthenium(II) chelates of the type [Ru(chel)3]2+, where chel is 2,2’-bipyridine, 2,2’-bipyrimidine or 2,2’-bipyrazine, in their ground states across the water/1,2-dichloroethane interface was classified as the reversible transfer of a divalent cation. Thermodynamic and transport parameters characterizing this transfer were obtained from voltammetric measurements. Photoexcitation of these chelates gives rise to the photoinduced charge transfer across the water/1,2-dichloroethane interface.
Simultaneous determination of hemoglobin and cysteine based on Brdička catalytic currents
Authors: Kuik Marian , Krassowski Kazimierz
Published: August 2009

The effect of the concentration of ammonia on the catalytic currents of bovine and human hemoglobin, cysteine, cystine and glutathione was studied, and the concentration of 3.5 mol l-1 was found optimal for analytical purposes. Mixtures of hemoglobin and cysteine exhibited catalytic wave positions suitable for their simultaneous quantitation. In a buffer containing 3.5 M ammonia, the catalytic current of hemoglobin is virtually independent of the concentration of cysteine, and at a constant concentration of hemoglobin, the catalytic current of cysteine increases linearly with its concentration over the range studied. Statistical evaluation gave evidence that hemoglobin and cysteine can be determined simultaneously in the above buffer. When accounting for some interfering effects with respect to the catalytic currents of glutathione and cysteine, complexation phenomena and properties of the hemoglobin surface layer must be taken into consideration.
Electrolytic coatings (layers) deposited from palladium(II) salts
Authors: Hlavatý Jaromír , Volke Jiří
Published: August 2009

In contrast to a number of investigations concerning preparation of layers and coatings of palladium(II) oxides this communication describes a reproducible electrolytic preparation from activation baths containing Pd(II) ions of coatings with hydrated palladium oxides, in particular on platinum supports. The voltammetric curves of coatings formed in such a way are reproducible over the whole pH range and exhibit an irreversible cathodic-anodic couple of peaks. For the voltammetric curve on an active layer deposited on a platinum support from a solution of Pd(NO3)2 at pH 7.03 Ekp is + 0.02 V and Eap +0.33 V (vs SCE). The observed character of the pH dependences for the peak potentials and current densities with a similar, mostly linear, behaviour has been also observed with layers deposited on glassy carbon or nickel. The deposited layers containing hydrated palladium oxides exhibit oxidative activity as follows from voltammograms in slightly acidic to neutral and strongly alkaline region. These curves point to the ability to oxidize not only ethanol but also toluene used as a with difficulty oxidizable model substrate.
Rapid scanning voltammetry under steady-state conditions in a flow through thin layer cell with a microelectrode
Authors: Tait Russel J. , Bond Alan M. , Finnin Barrie C. , Reed Barry L.
Published: August 2009

A microelectrode based detector system has been developed for measurement of steady state voltammetric curves in flowing solutions. Two microprocessors operating in parallel allow the direct transfer of collected data to a floppy diskette. Long term experiments can then be performed, with individual voltammograms being rapidly obtained, recorded and stored. The system can be used with scan rates up to 10 V s-1 and with 1 mV resolution over a potential range of 2.5 V. When a 10 μm diameter micro-disk platinum electrode serves as the working electrode, rapid scan voltammetry (scan rate 1 to 10 V s-1) can be undertaken under steady state conditions for reversible processes with a flow rate in the range of 1 to 3 ml min-1 as evidenced by the observation of sigmoidal rather than the peak shaped curves obtained with previously described rapid scan systems. That is, complete voltammograms can be obtained with minimal distortion due to uncompensated resistance and charging current which is not the case when conventionally sized electrodes are used or when microelectrodes are used at excessively high scan rates where linear diffusion terms become important. The working microelectrodes were developed to suit a conventional thin-layer cell design and therefore permit ready adaptation to existing flow through electrochemical detection systems. The detection limits for the determination of ferrocene in methanol at flow rates up to 3 ml min-1 were 10-6 mol dm-3 after background correction, and the response was found to be linear over the concentration range 10-3 to 10-6 mol dm-3. Three-dimensional methods of data treatment and contour plots can be used to interpret results obtained from steady state or near steady state voltammograms of incompletely resolved chromatograms as demonstrated with range of biologically important compounds.
Photochemical reactions with a participation of diffusion
Authors: Hrdina Radim , Čepčiansky Igor , Luňák Stanislav , Nepraš Miloš
Published: August 2009

Influence of diffusion coefficients of reaction components on a course of simple photochemical reactions has been studied by numerical simulation. Diffusion coefficients have been varied in the range <0,∞>. Relationship between values of diffusion coefficients and parameters of photochemical reactions (entry concentrations and absorptivities of components, intensity of incident light and quantum yield of corresponding photochemical reactions) have been shown.
Interactions of components and elements of the surface free energy at interfaces
Authors: Kloubek Jan
Published: August 2009

A new hypothesis is suggested for the evaluation of the components (γd and γab) and the elements (γa and γb) of the surface free energy. The respective equations are introduced for the interactions at interfaces between a non-polar acid and non-polar base, a polar phase and non-polar acid or base, and two polar phases. The dispersion component, γd, equals the total surface free energy of non-polar phases. However, they can interact at the interface as an acid or a base through their single permanent elements γa or γb, respectively. Otherwise, induced elements γia and γib can also be effective. The surface free energy of polar phases is additively composed of the dispersion, γd, and acid-base components, γab = 2(γaγb)1/2. The proposed equation are verified using the known values of the surface and interfacial free energies for the liquid-liquid systems and they are applied to the solid-liquid interfaces. The values of the elements are determined for water, γwa = 67.7 and γwb = 10.6 mJ/m2, and for other liquids, such as glycerol, formamide, mercury, benzene, diethyl ether and trichloromethane.
Oxidation of cumene by dioxygen. The effect of radical initiators on the rate of the reaction catalyzed by 3d-transition metal 2,4-pentanedionates
Authors: Luňák Stanislav , Chmelíková Růžena , Lederer Pavel
Published: August 2009

The effect of cumene hydroperoxide, benzoin ethyl ether and dibenzoyl peroxide on the oxidation of cumene by dioxygen catalyzed by VO(II), Cr(III), Mn(II), Fe(III), Co(II), Co(III) and Cu(II) 2,4-pentanedionates was studied. The rate of the catalyzed oxidation of cumene by dioxgen can not only be increased but also decreased by the presence of radical initiators, whereas in the absence of the catalyst the oxidation rate is always increased by the radical initiators. Which effect takes actually place is determined by the kind and oxidation state of the transition metal ion catalyst as well as by the kind of the radical initiator.
Azo coupling kinetics of benzenediazonium ions with citrazinic acid
Authors: Horáčková Jaroslava , Kaválek Jaromír , Kulič Jiří , Štěrba Vojeslav
Published: August 2009

Azo coupling kinetics of 4-methoxybenzenediazonium ion with 1,2-dihydro-6-hydroxy-2-oxopyridine-4-carboxylic acid (citrazinic acid, Ia) have been measured in dilute solutions of hydrochloric acid and in chloracetate, ethoxyacetate, acetate, and dihydrogenphosphate buffers. The reaction is subject to general base catalysis, i.e. splitting off of the proton from the tetrahedral intermediate is the rate-limit step. The rate constants have been measured for the azo coupling reaction with monoanion III (splitting off of the proton from OH group) and dianion. The rate constant with the monoanion III is only 4x smaller than that with the dianion and practically the same as that with the anion of citrazinic acid ester VIII. The azo coupling rte constants of the monoanion III have been determined for various substituted benzenediazonium ions, the ρ value found is 4.85.
Synthesis and antibacterial activity of some 1-(2-propynyl) and 1-propadienyl derivatives of 1,4-dihydro-4-oxoquinoline-3-carboxylic acids and similar heterocycles
Authors: Rádl Stanislav , Kovářová Lenka , Holoubek Jiří
Published: August 2009

N-Alkylation of IIIa, IIIb, IIId - IIIf and 9-acridanone with 3-bromopropyne in dimethyl sulfoxide in the presence of potassium carbonate yielded N-(2-propynyl) derivatives IVa - IVe and VIa, respectively. Ethyl esters IVa, IVb, and IVe were hydrolyzed to IVf - IVh, respectively. Compounds IVf, IVg, IVctreated with bases yielded N-propadienyl derivatives Va - Vc. On the other hand 2-substituted compounds IVd and IVh did not change under the same conditions. Compound VIa treated with powdered potassium hydroxide in dimethyl sulfoxide at room temperature yielded N-(1-propynyl) derivative VII.
Potential antidepressants and inhibitors of 5-hydroxytryptamine and noradrenaline re-uptake in the brain: N,N-Dimethyl-(arylthio)thenylamines and N,N-dimethyl-2-(thienylthio)benzylamines
Authors: Šindelář Karel , Pomykáček Josef , Valchář Martin , Dobrovský Karel , Metyšová Jiřina , Polívka Zdeněk
Published: August 2009

3-(3-Methoxyphenylthio)thiophene-2-carboxylic acid (IV) and 2-(3-methoxyphenylthio)thiophene-3-carboxylic acid (VII) were transformed via acid chlorides and dimethylamides to the amines V and VIII which were demethylated to the phenolic amines VI and IX. N,N-Dimethyl-4-bromothiophene-3-carboxamide (XI) was reacted with 3-methoxythiophenol and the amide XII was reduced and demethylated to the amine XIV. 2-(2-Thienylthio)benzoic acid (XVa) and 2-(5-bromo-2-thienylthio)benzoic acid (XVb) were transformed via the isolated acid chlorides and N,N-dimethylamides to the amines XVIIIa and XVIIIb. The amines VI, IX, and XIV are thiophene isosters of moxifetin, the potent inhibitor of 5-hydroxytryptamine re-uptake in the brain structures. Out of the compounds prepared, only the methoxy amine VIII (VUFB-17697) showed a similar type of activity. The intermediate V, the phenolic amine VI, and the hydroxyl group lacking amine XVIIIa are selective inhibitors of noradrenaline re-uptake in the brain.
Potential antidepressants and selective inhibitors of 5-hydroxytryptamine re-uptake in the brain: Synthesis of several potential metabolites of moxifetin and of two A-ring fluorinated analogues
Authors: Šindelář Karel , Pomykáček Josef , Holubek Jiří , Svátek Emil , Valchář Martin , Dobrovský Karel , Metyšová Jiřina , Polívka Zdeněk
Published: August 2009

A series of potential metabolites of the potent inhibitor of 5-hydroxytryptamine re-uptake in the brain structures – moxifetin (I) – i.e. the O-methylated and hydroxylated, further methoxylated, and N-monodemethylated analogues (III – VII, IX, and X) was synthesized from the acids XV, XIX, XXIIIa, XXIIIb, XXVIIa, and XXVIIb. The synthesis of III and V proceeded with protection of one hydroxyl group by benzyl and by the final debenzylation by short heating with hydrobromic acid. Compound IV was obtained by partial demethylation of N,N-dimethyl-(3-,4-dimethoxyphenylthio)benzylamine with sodium 4-toluenethiolate. Synthesis of VI, VII, IX, and X proceeded without protection of the hydroxyl group via the mixed anhydrides of the mentioned acids and methanesulfonic acid which were coupled with dimethylamine and the dimethylamides obtained were directly reduced to the final products. Two A-ring fluorinated analogues of I, i.e. VIII and XI were prepared from the acids XXIIIc and XXVIIc via acid chlorides, dimethylamides, and amines XXVIc and XXXc. The final step was demethylation by heating with hydrobromic acid. The N-oxide XII was obtained by oxidation of I with hydrogen peroxide in ethanol. Compounds III (VUFB-18285) and especially XI (VUFB-17724) were found to be selective inhibitors of the 5-hydroxytryptamine re-uptake in the brain. Some compounds (IV, VI, VII, X) indicate a similar type of activity. In addition to II (described previously), compounds IV and V were found to be moxifetin metabolites in the animals.
Chemical analysis: Information contribution of results
Authors: Eckschlager Karel
Published: August 2009

In this review, analysis is treated as a process of gaining information on chemical composition, taking place in a stochastic system. A model of this system is outlined, and a survey of measures and methods of information theory is presented to an extent as useful for qualitative or identification, quantitative and trace analysis and multicomponent analysis. It is differentiated between information content of an analytical signal and information gain, or amount of information, obtained by the analysis, and their interrelation is demonstrated. Some notions of analytical chemistry are quantified from the information theory and system theory point of view; it is also demonstrated that the use of fuzzy set theory can be suitable. The review sums up the principal results of the series of 25 papers which have been published in this journal since 1971.