Tunable optofluidic birefringent lens.

An optofluidic birefringent lens is demonstrated using hydrodynamic liquid-liquid (L(2)) interfaces in a microchannel. The L(2) lens comprises a nematic liquid crystal (NLC) phase and an optically isotropic phase for the main stream and the surrounding sub-stream, respectively. When the optofluidic device is subjected to a sufficiently strong electric field perpendicular to the flow direction, NLCs are allowed to orient along the external field rather than the flow direction overcoming fluidic viscous stress. The characteristics of the optofluidic birefringence lens are investigated by experimental and numerical analyses. The difference between the refractive indices of the main stream and the sub-stream changes according to the polarization direction of incident light, which determines the optical behaviour of the lens. The incidence of s-polarized light leads to a short focal point, while p-polarized light has a relatively long focal distance from the same L(2) interface. The curvatures and focal lengths of the lens are successfully evaluated by a hydrodynamic theory of NLCs and a simple ray-tracing model.

The role of copper in the thermal conductivity of thermoelectric oxychalcogenides: do lone pairs matter?

Understanding the underlying mechanisms that suppress thermal conduction in solids is of paramount importance for the targeted design of materials for thermal management and thermoelectric energy conversion applications. Bismuth copper oxychalcogenides, BiOCuQ (Q = Se, Te), are highly crystalline thermoelectric materials with an unusually low lattice thermal conductivity of ∼0.5 Wm(-1) K(-1), a value normally found in amorphous materials. Here we unveil the origin of the unusual thermal transport properties of these phases. First principles calculations of the vibrational properties combined with analysis of in-situ neutron diffraction data, demonstrate that weak bonding of copper atoms within the structure leads to an unexpected vibrational mode at low frequencies, which is likely to be a major contributor to the low thermal conductivity of these materials. In addition, we show that anharmonicity and the large Grüneisen parameter in these oxychalcogenides are mainly related to the low frequency copper vibrations, rather than to the Bi(3+) lone pairs.

Predictors of psychological adjustment, experienced parenting burden and chronic sorrow symptoms in parents of children with cerebral palsy.

AIM: To investigate the role of child behaviour, parental coping and experiential avoidance in predicting the psychological outcomes of: (i) psychological symptoms; (ii) chronic sorrow symptoms; and (iii) experienced parenting burden in parents of children with cerebral palsy (CP). METHOD: This study is a cross-sectional, correlational study. Ninety-four parents of children (aged 2-12 years) with CP (various levels of motor functioning GMFCS I-V) participated. RESULTS: Together, the three predictors of child behaviour, parental coping and experiential avoidance explained 36.8% of the variance in psychological symptoms with child behavioural problems and experiential avoidance as significant unique predictors. In addition, 15.8% of the variance in chronic sorrow symptoms was explained by the three predictors with experiential avoidance alone as a significant unique predictor. Lastly, the predictors together explained 24.3% of the variance in experienced parenting burden with child behavioural problems and experiential avoidance as significant unique predictors. CONCLUSIONS: This study demonstrates a relationship between child behavioural problems and parental psychological symptoms and experienced parenting burden as well as a relationship between experiential avoidance and parental psychological symptoms, experienced parenting burden and chronic sorrow symptoms.

Salivary duct carcinoma: what is already known, and can we improve survival?

Salivary duct carcinoma is an aggressive malignancy with a high mortality rate, which phenotypically resembles high-grade breast ductal carcinoma. The parotid gland is the most common location. Standard treatment is surgery to the primary tumour together with post-operative radiotherapy. Despite this, there is a high rate of local recurrence, cervical nodal involvement and distant metastasis. Chemotherapy is currently considered only for end-stage, disseminated disease; however, current evidence indicates that chemotherapy used with radiotherapy may result in improved disease control and survival.Human epidermal growth factor receptor-2 is a proto-oncogene which is over-expressed in both breast ductal carcinoma and salivary duct carcinoma. Clinical studies of patients with metastatic breast cancer, using trastuzumab, a monoclonal antibody directed against human epidermal growth factor receptor-2, have shown significant efficacy in tumour response, resulting in improved survival. Such advances in immunohistochemistry, and in targeted immunotherapy for breast ductal carcinoma, should be applied to the treatment of salivary duct carcinoma.

Systematic review of the efficacy of parenting interventions for children with cerebral palsy.

This systematic review aims to evaluate the efficacy of parenting interventions (i.e. behavioural family intervention and parent training) with parents of children with cerebral palsy (CP) on child behavioural outcomes and parenting style/skill outcomes. The following databases were searched: Medline (1950-April 2010), PubMed (1951-April 2010), PsycINFO (1840-April 2010), CINAHL (1982-April 2010) and Web of Science (1900-April 2010). No randomized clinical trials of parenting interventions with parents of children with CP were identified. Three studies were identified that involved the examination of a targeted parenting intervention via a pre-post design. Interventions utilized included the implementation of parenting interventions in conjunction with behavioural intervention and oral motor exercises for children with CP and feeding difficulties, the Hanen It Takes Two to Talk programme and a Functional Communication Training programme for parents. All studies found changes in relevant child behavioural outcomes. The studies reviewed suggest that parenting interventions may be an effective intervention for parents of children with CP. However, the current research is limited to pre-post designs of targeted parenting interventions (e.g. parenting interventions focused upon communication). A randomized controlled trial of parenting interventions for families of children with CP is urgently needed to address this paucity in the literature and provide families of children with CP with an evidence-based intervention to address child behavioural and emotional problems as well as parenting challenges.

Adult chiari malformation presenting as bilateral vocal cord paralysis.

In the Chiari malformations, herniation of the cerebellar tonsils through the foramen magnum into the cervical spinal canal can often result in headaches and spinal cord deficits. Bilateral vocal cord paralysis has been reported as a result of Chiari malformation but is rare and the vast majority of reports have been in the paediatric population. We report a case in a 68-year-old man with adult Chiari malformation where aspiration pneumonia from bilateral vocal cord palsy was the only manifestation of this malformation.

Endoscopic ligation of the sphenopalatine artery for refractory posterior epistaxis.

The management of patients with posterior epistaxis remains a challenging problem for the ENT surgeon. In most units, failure of conservative management results in more invasive techniques, involving either major artery ligation or percutaneous embolization of the internal maxillary artery. However, there are complications in more than 25% of patients undergoing these techniques. Endoscopic ligation of the sphenopalatine artery (ELSPA) is emerging as a minimally invasive alternative. We report our experience of ELSPA in 13 patients with a mean follow-up of 13 months. Epistaxis was controlled in 92% and to date no complications have been associated with the procedure. We conclude that ELSPA is a treatment option that is easy to perform and is safe and effective for patients with refractory posterior epistaxis.

The effects of critical incident stress debriefing (CISD) on emergency medical services personnel following the Los Angeles Civil Disturbance.

This study examined the effects of Critical Incident Stress Debriefing (CISD) upon technicians who provided emergency medical services in South Central Los Angeles during the 1992 Los Angeles Civil Disturbance. The relationships between exposure, debriefing and symptoms of stress were identified and examined. The Frederick Reaction Index-Adult (FRI-A) was used to measure the presence of symptoms characteristic of posttraumatic stress disorder. EMTs who had the opportunity to participate in Critical Incident Stress Debriefings (n = 42) following the incident reported fewer symptoms and scored significantly lower on the FRI-A than those not participating in Critical Incident Stress Debriefing (n = 23).

Pseudo-tumor cerebri and acne.

A case of pseudo-tumor cerebri is reported in a woman being treated with minocycline and tretinoin for acne who also ingested liver as a self-treatment for her condition. A possible cumulative effect between these agents is postulated.

Choriocarcinoma following term pregnancy--a case report.

A patient, with two previous term deliveries, presented with post-partum haemorrhage and spontaneous uterine perforation due to choriocarcinoma, requiring emergency laparotomy. Choriocarcinoma following term pregnancy is a rare form of gestational trophoblastic disease. Such tumour appears to follow a more aggressive course with a more extensive metastatic spread and is less responsive to chemotherapy resulting in a poorer prognosis. Choriocarcinoma presenting as postpartum haemorrhage, and spontaneous tumour perforation with intra-abdominal haemorrhage is even rarer. Early diagnosis is an important factor for the patient's survival. A high index of suspicion is required as the tumour may be overlooked. An aggressive chemotherapeutic regime has improved the overall survival.