Magnetic-field effects on the fragile antiferromagnetism in YbBiPt.

We present neutron-diffraction data for the cubic-heavy-fermion YbBiPt that show broad magnetic diffraction peaks due to the fragile short-range antiferromagnetic (AFM) order persist under an applied magnetic-field H . Our results for H ⊥ [ 1 ¯ 1 0 ] and a temperature of T = 0.14 1 K show that 1 2 , 1 2 , 3 2 ) magnetic diffraction peak can be described by the same two-peak line shape found for µ 0 H = 0 T below the Néel temperature of T N = 0.4 K . Both components of the peak exist for µ 0 H ≲ 1.4 T , which is well past the AFM phase boundary determined from our new resistivity data. Using neutron-diffraction data taken at T = 0.13 ( 2 ) K for H ∥ 0 0 1 taken at or 1 1 0 , we show that domains of short-range AFM order change size throughout the previously determined AFM and non-Fermi liquid regions of the phase diagram, and that the appearance of a magnetic diffraction peak at 1 2 , 1 2 , 1 2 at µ 0 H ≈ 0.4 T signals canting of the ordered magnetic moment away from 1 1 1 . The continued broadness of the magnetic diffraction peaks under a magnetic field and their persistence across the AFM phase boundary established by detailed transport and thermodynamic experiments present an interesting quandary concerning the nature of YbBiPt's electronic ground state.

Effect of Biaxial Strain on the Phase Transitions of Ca(Fe_{1-x}Co_{x})_{2}As_{2}.

We study the effect of applied strain as a physical control parameter for the phase transitions of Ca(Fe_{1-x}Co_{x})_{2}As_{2} using resistivity, magnetization, x-ray diffraction, and ^{57}Fe Mössbauer spectroscopy. Biaxial strain, namely, compression of the basal plane of the tetragonal unit cell, is created through firm bonding of samples to a rigid substrate via differential thermal expansion. This strain is shown to induce a magnetostructural phase transition in originally paramagnetic samples, and superconductivity in previously nonsuperconducting ones. The magnetostructural transition is gradual as a consequence of using strain instead of pressure or stress as a tuning parameter.

Tropospheric volatile organic compounds in China.

Photochemical smog, characterized by high concentrations of ozone (O3) and fine particles (PM2.5) in the atmosphere, has become one of the top environmental concerns in China. Volatile organic compounds (VOCs), one of the key precursors of O3 and secondary organic aerosol (SOA) (an important component of PM2.5), have a critical influence on atmospheric chemistry and subsequently affect regional and global climate. Thus, VOCs have been extensively studied in many cities and regions in China, especially in the North China Plain, the Yangtze River Delta and the Pearl River Delta regions where photochemical smog pollution has become increasingly worse over recent decades. This paper reviews the main studies conducted in China on the characteristics and sources of VOCs, their relationship with O3 and SOA, and their removal technology. This paper also provides an integrated literature review on the formulation and implementation of effective control strategies of VOCs and photochemical smog, as well as suggestions for future directions of VOCs study in China.

Evaluation of the effectiveness of air pollution control measures in Hong Kong.

From 2005 to 2013, volatile organic compounds (VOCs) and other trace gases were continuously measured at a suburban site in Hong Kong. The measurement data showed that the concentrations of most air pollutants decreased during these years. However, ozone (O3) and total non-methane hydrocarbon levels increased with the rate of 0.23 ± 0.03 and 0.34 ± 0.02 ppbv/year, respectively, pointing to the increasing severity of photochemical pollution in Hong Kong. The Hong Kong government has ongoing programs to improve air quality in Hong Kong, including a solvent program implemented during 2007-2011, and a diesel commercial vehicle (DCV) program since 2007. From before to after the solvent program, the sum of toluene, ethylbenzene and xylene isomers decreased continuously with an average rate of -99.1 ± 6.9 pptv/year, whereas the sum of ethene and propene increased by 48.2 ± 2.0 pptv/year from before to during the DCV program. Despite this, source apportionment results showed that VOCs emitted from diesel exhaust decreased at a rate of -304.5 ± 17.7 pptv/year, while solvent related VOCs decreased at a rate of -204.7 ± 39.7 pptv/year. The gasoline and liquefied petroleum gas vehicle emissions elevated by 1086 ± 34 pptv/year, and were responsible for the increases of ethene and propene. Overall, the simulated O3 rate of increase was lowered from 0.39 ± 0.03 to 0.16 ± 0.05 ppbv/year by the solvent and DCV programs, because O3 produced by solvent usage and diesel exhaust related VOCs decreased (p < 0.05) by 0.16 ± 0.01 and 0.05 ± 0.01 ppbv/year between 2005 and 2013, respectively. However, enhanced VOC emissions from gasoline and LPG vehicles accounted for most of the O3 increment (0.09 ± 0.01 out of 0.16 ± 0.05 ppbv/year) in these years. To maintain a zero O3 increment in 2020 relative to 2010, the lowest reduction ratio of VOCs/NOx was ∼1.5 under the NOx reduction of 20-30% which was based on the emission reduction plan for Pearl River Delta region in 2020.

Computational investigation into the gas-phase ozonolysis of the conjugated monoterpene α-phellandrene.

Reaction with ozone is a major atmospheric sink for α-phellandrene, a monoterpene found in both indoor and outdoor environments, however experimental literature concerning the reaction is scarce. In this study, high-level G4(MP2) quantum chemical calculations are used to theoretically characterise the reaction of ozone with both double bonds in α-phellandrene for the first time. Results show that addition of ozone to the least substituted double bond in the conjugated system is preferred. Following addition, thermal and chemically activated unimolecular reactions, including the so-called hydroperoxide and ester or 'hot' acid channels, and internal cyclisation reactions, are characterised to major first generation products. Conjugation present in α-phellandrene allows two favourable Criegee intermediate reaction pathways to proceed that have not previously been considered in the literature; namely a 1,6-allyl resonance stabilised hydrogen shift and intramolecular dioxirane isomerisation to an epoxide. These channels are expected to play an important role alongside conventional routes in the ozonolysis of a-phellandrene. Computational characterisation of the potential energy surface thus provides insight into this previously unstudied system, and will aid future mechanism development and experimental interpretation involving α-phellandrene and structurally similar species, to which the results are expected to extend.

Photochemical trajectory modeling of ozone concentrations in Hong Kong.

In this study, tropical cyclones over the East and South China Seas were found to be the most predominant weather conditions associated with the occurrence of high ozone (O3) episodes in Hong Kong in 2005-2009. A photochemical trajectory model coupled with Master Chemical Mechanism (MCM) was adapted to simulate the O3 concentrations during two O3 pollution episodes. The results agreed well with the observed data. A representative backward air mass trajectory was used to determine the contribution of each volatile organic compound (VOC) to the O3 levels. After taking into account both reactivity and mass emission of each VOC, 10 species were found to be the key O3 precursors in Hong Kong. Further analysis identified solvent related products accounting for 70% of the modeled O3 concentration in Hong Kong. The results highlight the importance of considering together reactivity and source sector emissions in developing targeted VOC reduction for O3 abatement strategies.

Insight of scent: experimental evidence of olfactory capabilities in the wandering albatross (Diomedea exulans).

Wandering albatrosses routinely forage over thousands of kilometres of open ocean, but the sensory mechanisms used in the food search itself have not been completely elucidated. Recent telemetry studies show that some spatial behaviours of the species are consistent with the 'multimodal foraging strategy' hypothesis which proposes that birds use a combination of olfactory and visual cues while foraging at sea. The 'multimodal foraging strategy' hypothesis, however, still suffers from a lack of experimental evidence, particularly regarding the olfactory capabilities of wandering albatrosses. As an initial step to test the hypothesis, we carried out behavioural experiments exploring the sensory capabilities of adult wandering albatrosses at a breeding colony. Three two-choice tests were designed to investigate the birds' response to olfactory and visual stimuli, individually or in combination. Perception of the different stimuli was assessed by comparing the amount of exploration directed towards an 'experimental' display or a 'control' display. Our results indicate that birds were able to perceive the three types of stimulus presented: olfactory, visual and combined. Moreover, olfactory and visual cues were found to have additional effects on the exploratory behaviours of males. This simple experimental demonstration of reasonable olfactory capabilities in the wandering albatross supports the 'multimodal foraging strategy' and is consistent with recent hypotheses of the evolutionary history of procellariiforms.

A novel method of shortening an aortic graft.

We describe a simple method of shortening the abdominal aortic graft during an emergency procedure which is easy to perform and does not unduly delay the completion of the operation.

Pretreatment correlates of the therapeutic bond.

This study examined the association between pretreatment client characteristics and the therapeutic bond, which is defined as the emotional aspect of the therapeutic alliance. Three types of interpersonal problems and four indicators of emotional distress were measured and compared to the therapeutic bond and its subscales (role investment, empathic resonance, and mutual affirmation) measured early in treatment. Interpersonal problems related to being overly detached were associated with a poorer quality bond and, in particular, with a tendency to feel as if the therapist does not understand what the client is thinking and feeling (lower empathic resonance). Higher levels of distress were correlated negatively with the therapeutic bond. Analyses indicated that interpersonal problems were better predictors of the bond than was distress. The relevance of these findings for practitioners is discussed.

Syzygy, science, and psychotherapy: the Consumer Reports study.

Results from a Consumer Reports (CR) survey indicated that psychotherapy has proven to be quite effective and that longer-term therapy has been more effective than shorter-term therapy. Critiques of the methodology of this study have included the claim that (a) the self-selected sample was biased in favor of people who felt that they had benefited from psychotherapy, (b) the use of retrospective accounts led to a further positive bias, and (c) the validity of the outcome assessment was questionable. Supplemental data from other sources, including prospective data from a large sample of psychotherapy patients, are presented to augment the interpretation of the results of the CR study and to illustrate how some critiques of research results can be evaluated systematically.

Characterization of the reactivities of volatile organic compounds using a master chemical mechanism.

A comprehensive description of the ozone-forming potentials of 101 organic compounds has been constructed under North American urban "averaged conditions" using a detailed master chemical mechanism and a simple air parcel trajectory model. This chemical mechanism describes the reactions of 3603 chemical species taking part in more than 10,500 chemical reactions. An index value has been calculated for each organic compound, which describes the increment in ozone concentrations found downwind of an urban area following the emission of a fixed increment in the mass emission of each organic compound. These indices, termed photochemical ozone creation potentials (POCPs), have been expressed on a scale relative to ethylene (ethene) = 100, and, a reactivity scale has been generated for alkanes, alkenes, and oxygenated and halogenated organic compounds. A high degree of correlation (R2 = 0.9) was found between these POCP values and the most widely accepted urban reactivity scale. While the reactivities of most of the 86 organic compounds compared fell within a consistent range, significant discrepancies were found for only 5 compounds. Single-day or multiday conditions appear to be important in establishing quantitative reactivity scales for the less reactive organic compounds.

Malignant T-cell lymphoma mimicking lepromatous leprosy.

We describe a 16-year-old Filipino boy who presented with skin lesions highly suggestive of lepromatous leprosy, but further assessment established a diagnosis of malignant T-cell lymphoma. This case emphasizes the extensive differential diagnosis of leprosy, as well as the importance of obtaining skin biopsies for diagnostic confirmation.

Clients' assessment of the affective environment of the psychotherapy session: relationship to session quality and treatment effectiveness.

This study investigated clients' affective experience during therapy. Clients (N= 268) completed Therapy Session Reports (TSR) in an early session of treatment. The two sections of the TSR that assess how the client felt and how the client perceived the therapist to be feeling were combined and factor analyzed. Six stable and meaningful factors were derived (Client Distressed, Client Remoralized, Reciprocal Intimacy, Therapist Confident Involvement, Client Inhibited, and Therapist Distracted). Affect scale scores were created and compared to session quality and treatment effectiveness. Clients' affective experience was highly correlated with patient-rated session quality. The association between clients' affective experience during the session and treatment effectiveness was fairly strong for relatively brief therapy but insignificant for relatively lengthy treatment. The implications for practitioners, who--in contrast to most measures of therapeutic process--have easy access to clients' in-session emotional experiences, are discussed.

Individual psychotherapy outcome and process research: challenges leading to greater turmoil or a positive transition?

Psychotherapy is facing challenges that relate to the emergence of managed health care, the possibility of a national health care system, and advances in biological psychiatry. These situations have created pressure to achieve a more accurate assessment of psychotherapeutic effectiveness. Psychotherapy has been proven to be generally effective; however, there is uncertainty as to why. The field is currently experiencing apparent turmoil in three areas: (a) theory development for psychotherapeutic effectiveness, (b) research design, and (c) treatment technique. This chapter reviews the dynamics within each of the areas and highlights the progress made in treating mental disorders. We conclude that recent advances in research design may provide a transition that will bring psychotherapy closer to becoming a unified paradigm with an acceptable theory of effectiveness.

Patterns of mental health service utilization.

How many and which individuals, with which psychiatric disorders, receive (and do not receive) mental health services from which professionals in what settings? This question falls within the purview of mental health services research, which is a multidisciplinary field that brings together the methodologies of epidemiology, econometrics, and clinical research. First, in this article, we present an explication of what is known about those individuals in need of psychotherapy and how they access services. Next, we describe the numbers, professional affiliations, and service sites of professionals who are engaged in the practice of psychotherapy. We summarize our current knowledge about the actual utilization of psychotherapy services relative to the needs of patients and the professional background of therapists. Finally, we identify aspects of psychotherapy service utilization that are, as yet, unaddressed.

A shooting incident in an elementary school: effects of worker stress on public safety, mental health, and medical personnel.

The effects of impact of event and five categories of worker stress were studied with 140 police, fire, medical, and mental health personnel who were involved in emergency service work following a shooting in an elementary school. A questionnaire distributed 6 months after the incident was utilized. Public safety personnel reported a recollection of significantly fewer intrusive thoughts than medical and mental health professionals immediately following the incident. Groups did not differ in intrusive or avoidance scores on the Impact of Event Scale 6 months after the event and all groups showed a significant decrease in both scores over time. Stepwise linear regression showed that a self-reported qualitatively heavy work load predicted intrusiveness and avoidance of thoughts both immediately after and at the 6-month anniversary of the incident. Additionally, time pressure and quantitatively heavy work load also predicted avoidance score at the time of the incident. Results are discussed in terms of control models of anxiety and as foci for debriefing with affected personnel.