Vacancy-mediated structural changes in Au–Cu nanoparticles

We report the formation of new phases in bimetallic Au–Cu nanoparticles. These phases were observed in nanoparticle synthesised by adopting a three-step protocol in a single pot. Nanoparticles at 180°C for 1?h led to the formation of single-phase solid solution of Cu in Au. Subsequent heat treatment at 290°C for 2?h of these Au–Cu nanoparticles revealed three new phases. One of them relates to the modification of occupancy of Cu in an ordered AuCu tetragonal phase (tP4). This cell although retains tetragonal symmetry but displays metrical properties akin to that of a cube. The other two relates to vacancy ordering along <111> directions in the {111} planes of an ordered AuCu3 cubic phase (cP4). On the one hand, statistical occupancy of vacancy on Cu site in this cell leads to the reduction of cell size from ～3.75?Å to ～3.5?Å whereas ordering of vacant layer on the other hand gives rise to symmetry breaking. Former continues to display cubic symmetry whereas latter transforms to a trigonal cell.     

Influence of Zn incorporation on the microstructural and magnetic properties of La0.67Sr0.33Mn1−xZnxO3 nanoparticles synthesised by the sol–gel method

Perovskite manganite nanoparticles with the chemical formula La_0.67Sr_0.33Mn_1?xZn_xO₃ (x = 0, 0.1 and 0.2) were prepared by the sol–gel process and the influence of Zn substitution on their microstructural and magnetic properties studied in detail. X-ray diffractometry (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed for crystal structure determination and microstructural analysis. The results of XRD analysis confirmed the polycrystalline nature and rhombohedral crystal structure with space group R(-3c) for all compositions. SEM micrographs of the samples revealed an agglomeration/well-connected appearance of the particles. The composition and uniform distribution of all the elements were established by energy-dispersive spectroscopy. TEM images clearly confirmed an almost spherical shape of the nanoparticles with an average particle size of about 11, 14 and 13 nm for the 0, 10 and 20% Zn-doped samples, respectively. The magnetic behaviour of the nanoparticles was studied at room temperature with a vibrating sample magnetometer (VSM) up to a field of 1.8 Tesla. These measurements established a superparamagnetic nature with a variation in the saturation magnetization (M_s) with Zn content.     

Effect of metastable Cr(Mo)s/Cr(Mo)a powders on mechanical alloying the immiscible Cu–Mo–Cr system

Metastable-state alloy powders are usually synthesised by milling and occur as products of mechanical alloying (MA), but they are rarely used as starting materials for other MA processes. In this work, metastable-state alloy powders, including supersaturated solid-solution Cr(Mo)s and amorphous Cr(Mo)a were prepared in advance. Then, the Cr(Mo)s/Cr(Mo)a powder mixture was mechanically alloyed with elemental Cu to form Cu–Mo–Cr alloy. The effects of the metastable-state powder Cr(Mo)s/Cr(Mo)a on MA of the immiscible Cu–Mo–Cr system were evaluated. Phases and microstructures of the milled powders were analysed by XRD and TEM, respectively. The results show that amorphous Cu-60wt.%Cr(Mo) and supersaturated solid-solution Cu-20wt.%Cr(Mo) alloy powders can be synthesised by MA. It is concluded that MA of the Cu–Mo–Cr ternary alloy system is significantly promoted when elemental Cu powder is milled with metastable-state alloy powder Cr(Mo)s/Cr(Mo)a. Furthermore, the promoting effect of amorphous Cr(Mo)a on MA the Cu–Mo–Cr alloy system is much greater than that of supersaturated solid-solution Cr(Mo)s, during the milling process.     

Visuospatial processing in adolescents with critical congenital heart disease: Organization,integration, and implications for academic achievement

Among the most significant factors affecting quality of life in individuals with critical congenital heart disease (CCHD) are neurodevelopmental challenges, including deficits in visuospatial processing and academic achievement. Few studies have compared outcomes across CCHD subgroups, despite their significant differences in anatomy/physiology and medical/surgical courses. This study compared visuospatial processing abilities using the Developmental Scoring System for the Rey–Osterrieth Complex Figure (DSS-ROCF) across groups of adolescents with CCHD (d-transposition of the great arteries [TGA, n = 139], Tetralogy of Fallot [TOF, n = 68], single-ventricle cardiac anatomy requiring the Fontan operation [SVF, n = 145]) and a group of healthy controls (CTR, n = 111), and examined the validity of visuospatial processing in predicting concurrent academic outcomes. The CCHD subgroups were found to differ in Organization, ps < .001, Structural Accuracy, ps < .001, and Incidental Elements Accuracy scores, ps ≤ .008; the post hoc analyses show that the SVF group tended to underperform compared to the other CCHD groups. With respect to academic skills, all CCHD groups scored lower than the CTR group, ps ≤ .007; however, the CCHD groups were not different from each other, ps > .23. The regression results showed that the DSS-ROCF Style rating (reflecting integration) accounted for a small yet statistically significant portion of unique variance in “assembled” academic outcomes, over and above the variance already accounted for by DSS-ROCF Organization, p < .01. These findings support the need for comprehensive neuropsychological assessment and monitoring of children and adolescents with CCHD, as well as targeted intervention for organization and integration deficits that may increase their risk for academic underachievement.     

South Asian American Daughter–Father Relationships in the Aftermath of Maternal Loss

ABSTRACT

In this transcendental phenomenological study, we interviewed five South Asian American daughter–father dyads regarding their experiences of coping and resiliency in the aftermath of maternal/spousal loss. Mothers play a crucial role in immigrant families as they serve not only as caregivers, but also as the main people who facilitate the transmission of culture. An untimely death of mothers in immigrant families can lead to confusion of roles within the family subsystems. Three main themes emerged for daughters from the interviews: (a) re-grieving, (b) coping/resiliency, and (c) daughter’s relationship with father following maternal loss. Three themes also emerged from the interviews with the fathers: (a) lack of traditional sources of familial support, (b) coping/resiliency, and (c) relationship with daughter following spousal loss. We utilized dyadic analysis to examine the dynamics of the daughter–father relationship. Overall, in the aftermath of maternal loss, the families experienced significant reorganization in its structure and reassignment of roles. For many of the daughters, cultural norms of patriarchy and traditional gender roles explained their pattern of assuming more responsibility in the household after the death of their mothers. Findings also showed how the intersection of gender, culture, and immigration status contributed to the process of complicated grief following maternal loss and the struggles experienced with reorganization of familial roles, rules, and expectations for South Asian American daughters and their fathers. Results from this study have implications for future research and clinical practice.     

Mirroring effects: Using psychodynamic-oriented video feedback to work on dyadic risk. A pilot experience

This study examines the qualitative and quantitative effects of a short-term, psychodynamically oriented video-feedback intervention in an Italian sample (n = 30) of non-clinical mothers with high potential dyadic risk due to work–family conflict. We adopted a psychodynamically informed and video-assisted approach based on theoretical and clinical assumptions that are used in psychodynamically oriented dialogue and observations. We proposed a cycle of four clinically oriented consultations including a single video feedback session, using the CARE-Index for both assessment and intervention. Independent t-tests were computed to evaluate how effective the programme was in reducing parental stress. We present two case examples in order to discuss the process of change in maternal attitudes activated by the programme. Quantitative findings revealed a drastic reduction of the participants’ resistance in recognising conflictual aspects of their parenting experience. From a qualitative perspective, the video feedback programme solicited three psychic functions: mirroring, resignifying and repairing. We highlight the key role of the observer’s countertransference and of her relationship with the mother in creating a safe and transformative setting. Results are encouraging in using our programme to help mothers to improve their holding function. We discuss possibilities for reinforcing the relevant changes obtained by extending the programme.     

The messianic temporality of theatre in I. L. Peretz’s At Night in the Old Marketplace

Theatre, as an art form that unfolds through time and moulds temporal experience, engages with its surrounding culture’s temporal imagination, the ways in which society conceives time, its movement, structures, and meaning. I. L. Peretz’s enigmatic and avant-garde Yiddish drama, At Night in the Old Marketplace, utilizes this potential of the theatre to tackle the question of messianic time and the ways in which it can be realized on the stage. By evoking Jewish traditions regarding the Messiah, religious nocturnal rituals, and the dynamics of Carnival, Peretz reconfigures messianic time as a radical, recurring yet fleeting, temporal experience. Theatrical temporality has affinities with messianic time because both are transitory and charged, condensed and ephemeral, and disjointed from the experience of time in everyday life. Rather than imagining messianic time as an eternal future to be awaited, Peretz’s play invites us to ponder in the theatre about the possibility of a messianically charged, albeit always fleeting, present.     

Why Bioethics Should Be Concerned With Medically Unexplained Symptoms

Biomedical diagnostic science is a great deal less successful than we've been willing to acknowledge in bioethics, and this fact has far-reaching ethical implications. In this article I consider the surprising prevalence of medically unexplained symptoms, and the term's ambiguous meaning. Then I frame central questions that remain answered in this context with respect to informed consent, autonomy, and truth-telling. Finally, I show that while considerable attention in this area is given to making sure not to provide biological care to patients without a need, comparatively little is given to the competing, ethically central task of making sure never to obstruct access to biological care for those with diagnostically confusing biological conditions. I suggest this problem arises from confusion about the philosophical value of vagueness when it comes to the line between biological and psychosocial needs.     

Sense of Coherence and Posttraumatic Growth: The Moderating Role of Value Orientation in Chinese and Swiss Bereaved Parents

Sense of Coherence–Revised (SOC-R) and posttraumatic growth (PTG) can be understood as two metaheuristics that are closely linked to resilience and adaption to adversity. This study investigated the association between SOC-R and PTG, as well as the moderating role of value orientations, in a sample of 67 Chinese and Swiss parents who lost their child. Results showed that, cross-culturally, the value of conservation was negatively associated with PTG, and self-transcendence showed a significant moderation effect to enhance the positive relationship between SOC-R and PTG. Implications for clinical practice to facilitate growth by focusing on SOC-R and value orientations were discussed.