Investigation of Opto-Mechanics in Thin-Film Photonic Crystal Membranes

Opto-mechanical interactions in photonic crystals (PC) require further investigation for their realization in practical applications. In particular their dynamic response and opto-mechanical coupling is not well understood. The static response of a thin-film 2D PC membrane was studied and the mechanical sensitivity of a static pressure sensor was increased by a factor of 4.9 times. A novel model formulation, correctly accounting for the fluid-structure interaction and the influence of nano-features, was developed to describe the dynamic response of a thin-film 2D PC membrane. The model accurately predicted damping response to within 10% as compared to experimental measurements. A novel 2D PC device was designed to evaluate the different coupling regimes of the opto-mechanical interaction by altering mechanical (Gamma) and optical (kappa) loss. A maximum bare opto-mechanical coupling coefficient of 12.78MHz was obtained

Numerical study of stability and connectivity of vertical goaf drainage holes

During underground longwall coal extraction, overburden strata deformation may result in vertical goaf drainage holes, which are drilled in advance of mining for tail gate gas management, to fail. The performance of these vertical goaf drainage holes is controlled by mine design parameters and local geomechanical properties. This paper investigates the use of advanced 3D finite element modelling and 2D discrete element modelling simulation techniques to understand the fundamentals of vertical goaf drainage hole failure mechanism due to strata shear at a currently operating gassy Australian mine site. Finite element modelling is used to investigate the location of high shear in the overburden strata at the vertical goaf gas drainage hole region during longwall mining and the discrete element modelling is used to examine connectivity from the goaf region to the goaf-gas drainage system.The Anglo-American Metallurgical Coal, Australiahttp://link.springer.com/journal/107062022-01-02hj2021Mining Engineerin

Fact or Factitious? A Psychobiological Study of Authentic and Simulated Dissociative Identity States

BACKGROUND: Dissociative identity disorder (DID) is a disputed psychiatric disorder. Research findings and clinical observations suggest that DID involves an authentic mental disorder related to factors such as traumatization and disrupted attachment. A competing view indicates that DID is due to fantasy proneness, suggestibility, suggestion, and role-playing. Here we examine whether dissociative identity state-dependent psychobiological features in DID can be induced in high or low fantasy prone individuals by instructed and motivated role-playing, and suggestion. METHODOLOGY/PRINCIPAL FINDINGS: DID patients, high fantasy prone and low fantasy prone controls were studied in two different types of identity states (neutral and trauma-related) in an autobiographical memory script-driven (neutral or trauma-related) imagery paradigm. The controls were instructed to enact the two DID identity states. Twenty-nine subjects participated in the study: 11 patients with DID, 10 high fantasy prone DID simulating controls, and 8 low fantasy prone DID simulating controls. Autonomic and subjective reactions were obtained. Differences in psychophysiological and neural activation patterns were found between the DID patients and both high and low fantasy prone controls. That is, the identity states in DID were not convincingly enacted by DID simulating controls. Thus, important differences regarding regional cerebral bloodflow and psychophysiological responses for different types of identity states in patients with DID were upheld after controlling for DID simulation. CONCLUSIONS/SIGNIFICANCE: The findings are at odds with the idea that differences among different types of dissociative identity states in DID can be explained by high fantasy proneness, motivated role-enactment, and suggestion. They indicate that DID does not have a sociocultural (e.g., iatrogenic) origin

Stress analysis of longwall top coal caving

Longwall top coal caving (LTCC) is a relatively new method of mining thick coal seams that is currently achieving high productivity and efficiency in application, particularly in China. The technique is similar to traditional longwall mining in that a cutting head slices coal from the lower section of the coal seam onto a conveyor belt installed in front of the hydraulic support near the cutting face. In modern LTCC an additional rear conveyor belt is located behind the support, to which the flow of the caved coal from the upper part of the seam can be controlled by a moveable flipper attached to the canopy of the support. The mining method relies on the fracturing of the top coal by the front abutment pressure to achieve satisfactory caving into the rear conveyor. This paper develops a yield and caveability criterion based on in situ conditions in the top coal in advance of the mining face (yield) and behind the supports (caveability). Yielding and caving effects are combined into one single number called caving number (CN), which is the multiplication result of caving factor (CF) and yield factor (YF). Analytical derivations are based on in situ stress conditions, Mohr-Coulomb and/or Hoek-Brown rock failure criteria and a non-associated elastoplastic strain softening material behaviour. The yield and caveability criteria are in agreement with results from both numerical studies and mine data. The caving number is normalised to mining conditions of a reference Chinese mine (LMX mine) and is used to assess LTCC performance at fourteen other Chinese working longwalls that have had varying success with the LTCC technology. The caving number is found to be in good agreement with observations from working LTCC mines. As a predictive model, results of this analytical/numerical study are useful to assess the potential success of caving in new LTCC operations and in different mining conditions. © 2009 Elsevier Ltd

Health professionals' detection of depression and anxiety in their patients with diabetes: the influence of patient, illness and psychological factors

This study examines how often depression and anxiety, in patients with diabetes, are detected by health professionals; and whether detection is influenced by patient characteristics (age, gender), illness factors (duration of illness, diabetes control), and self-reported levels of depression and anxiety. Prevalence rates of clinically significant depression and anxiety were high (57% and 36%, respectively); however, of those identified, only 44 and 36 per cent, respectively, were detected by staff as depressed or anxious. The only significant predictors of detection were severity of depressive and anxious symptoms. Patient and illness characteristics did not influence whether professionals identified emotional problems in their patients

Health professionals' detection of depression and anxiety in their patients with diabetes: the influence of patient, illness and psychological factors

This study examines how often depression and anxiety, in patients with diabetes, are detected by health professionals; and whether detection is influenced by patient characteristics (age, gender), illness factors (duration of illness,diabetes control), and self-reported levels of depression and anxiety. Prevalence rates of clinically significant depression and anxiety were high (57% and 36%,respectively); however, of those identified, only 44 and 36 per cent,respectively, were detected by staff as depressed or anxious. The only significant predictors of detection were severity of depressive and anxious symptoms. Patient and illness characteristics did not influence whether professionals identified emotional problems in their patients

School-based psychological screening in the aftermath of a disaster: are parents satisfied and do their children access treatment?

This study investigated parents' satisfaction with postdisaster school-based screening and whether satisfaction was related to follow-through with screening recommendations. From among 1,268 there were 224 children, ages 7–18 years (M = 10.97, SD = 2.44 years) screened for emotional distress 4 months after a flood and 130 parents who completed the screening evaluation. Of the 44 children who showed severe emotional distress, less than 50% of their parents reported concerns and only 29.5% had sought assistance. Following screening, 86.7% of these children completed treatment. Overall satisfaction ratings by parents were high, with 99.2% very or mostly satisfied