Non-interferometric Test of Collapse Models in Optomechanical Systems

The test of modifications to quantum mechanics aimed at identifying the fundamental reasons behind the un-observability of quantum mechanical superpositions at the macro-scale is a crucial goal of modern quantum mechanics. Within the context of collapse models, current proposals based on interferometric techniques for their falsification are far from the experimental state-of-the-art. Here we discuss an alternative approach to the testing of quantum collapse models that, by bypassing the need for the preparation of quantum superposition states might help us addressing non-linear stochastic mechanisms such as the one at the basis of the continuous spontaneous localisation model.Comment: 6 pages, accepted for publication in Phys. Rev. Lett.

Thermal Assessment of Convective Heat Transfer in Air- Cooled PEMFC Stacks: An Experimental Study

AbstractThis study presents an experimental stack-level thermal and hydrodynamic assessment of a model air-cooled PEM fuel cell. To mimic the heat generation inside the MEA, rubber heater films are used. Pressure drop along the stack channels and temperature distribution on the bipolar plate surface are measured for the channel Reynolds number range of 200-500 and the stack input power range of 100-250W. Tests are performed with and without gas diffusion layers (GDL) to investigate the effect of GDL and its surface characteristics on the pressure drop and heat transfer. Our results indicate that, with the existing length of bipolar plates, a major part of plate minichannel is filled with the developing region. This leads to a higher heat transfer rates, thus more uniform stack temperature can be obtained with the penalty of higher fan power. The minimum measured temperature difference is about 10°C and the values become more pronounced when the Reynolds number decreases. The existence of the GDL is observed to have negligible effect on the pressure drop

Effect of fasting on levels of subjective stress among nurses working in emergency departments of hospitals in chahar mahal and bakhtiari‏

Background: High levels of stress in nurses, known as a factor influencing the level of job satisfaction and can result in poor performance and dissatisfaction of patients. Therefore, the use of stress reduction programs, such as adherence to religion and religious teachings seriously, to protect and prevent health problems, it is very necessary and inevitable. Objectives: The aim of this study is to investigate the effect of fasting on the subjective stress level of nurses working in emergency departments is subjective. Materials and Methods: This study was a prospective study that performed on 110 nurses working in emergency departments of hospitals in Chahar Mahal and Bakhtiari. Sampling method was Simple and the sample of this study was the same. To gathering of information demographic and subjective stress questionnaire was used to measure subjective stress. Questionnaires completed in 3 phases: before, half and after the Ramadan. For data analyzing descriptive and inferential statistics such as t-test and the test based on Friedman repeated SPSS software data were used. Results: The results of this study showed before Ramadan, subjective stress level of emergency nurses was 23.48 ± 14.52 and in the middle of Ramadan 20.65 ± 9.96 and after Ramadan 7.55 ± 4.64.These figures indicate the end of Ramadan, the subjective stress level as low as emergency nurses as it has been before and middle of Ramadan. Discussion: The results of this study showed that a positive impact of Ramadan fasting on improving the subjective health of emergency nurses. Due to the sensitivity of Professional nurses, are constantly affected by stress and if this group, note not to physical and mental health, this would in turn improve

Are collapse models testable with quantum oscillating systems? The case of neutrinos, kaons, chiral molecules

Collapse models provide a theoretical framework for understanding how classical world emerges from quantum mechanics. Their dynamics preserves (practically) quantum linearity for microscopic systems, while it becomes strongly nonlinear when moving towards macroscopic scale. The conventional approach to test collapse models is to create spatial superpositions of mesoscopic systems and then examine the loss of interference, while environmental noises are engineered carefully. Here we investigate a different approach: We study systems that naturally oscillate --creating quantum superpositions-- and thus represent a natural case-study for testing quantum linearity: neutrinos, neutral mesons, and chiral molecules. We will show how spontaneous collapses affect their oscillatory behavior, and will compare them with environmental decoherence effects. We will show that, contrary to what previously predicted, collapse models cannot be tested with neutrinos. The effect is stronger for neutral mesons, but still beyond experimental reach. Instead, chiral molecules can offer promising candidates for testing collapse models.Comment: accepted by NATURE Scientific Reports, 12 pages, 1 figures, 2 table

Heterogeneous catalytic ozonation of 2, 4-dinitrophenol in aqueous solution by magnetic carbonaceous nanocomposite: catalytic activity and mechanism

Herein, the catalytic properties of a carbonaceous nanocomposite in the catalytic ozonation process (COP) of 2, 4-dinitrophenol (2, 4-DNP) were investigated and the results were compared with those obtained from single ozonation process (SOP). Magnetic carbonaceous nanocomposite, as a novel catalyst, was applied to optimize the condition for the removal of 2, 4-DNP in the COP, and the influential parameters such as pH, catalyst dosage, addition of radical scavengers, and durability were all evaluated. The results showed that the degradation efficiency of 2, 4-DNP and COD in the COP (98.2, 92) was higher compared to the SOP (75, 61) and the highest catalytic potential was achieved at an optimal pH of 6. The first-order modeling demonstrated that the reactions were dependent on the concentration of the catalyst, with the kinetic constants varying from 0.022 (1/min) in the SOP to 1.377 (1/min) in the COP at the catalyst dosage of 4 g/L and the optimum concentration of catalyst (2 g/L). The addition of radical scavenger noticeably diminished the removal efficiency of 2, 4-DNP in the SOP from 75 down to 54, while the corresponding values for the COP dropped from 98.2 to 93. Furthermore, a negligible reduction in the catalytic properties of the catalyst was observed (~5) after five-time reuse. The results also revealed that the applied method is effectively suitable for the removal of 2, 4-DNP contaminant from industrial wastewaters. © 2015 Balaban Desalination Publications. All rights reserved

The effects of Anethum graveolens essence on scopolamine-induced memory impairment in mice

Since Anethum graveolens (Dill) has phytoestrogenic compounds and it is proven that estrogens exert beneficial effects on cognition; the aim of this study was to understand if this plant can improve memory performance. Male Balb/c mice weighing 25-30 g were used in this study and memory was assessed by the novel object recognition task. In this method, the difference in the exploration time between a familiar object and a novel object is taken as an index of memory performance (recognition index, RI). Scopolamine significantly reduced memory index (RI = -15.5% ± 3.0). Dill essence (100 mg/kg, ip) prevented the harmful effects of scopolamine on memory (RI = 40% ± 5.5), thus RI did not differ with control animals (RI = 50% ± 5.8). In addition, 17-β estradiol also prevented memory impairment in animals (0.2 mg/kg, ip; RI = 35.8% ± 6.5). Nevertheless, the beneficial effects of dill essence were antagonized by prior injection of tamoxifen (1 mg/kg, ip; RI = -30% ± 7.8). Although phytoesrogens are not steroids, the beneficial effect of dill on memory, at least in part, may have been achieved by estrogenic receptors present in the brain. Thus dill essence could be promising in improving memory and cognition, mainly in postmenopausal women

The effectiveness of a supportive educative group intervention on family caregiver burden of patients with heart failure.

BACKGROUND Living with heart failure patients is a complex situation for family caregivers. Few studies have been conducted to examine the effects of interventional programs to ease this condition. The purpose of this study was to determine the effectiveness of a supportive educative group intervention in reducing family caregivers' burden of caregiving. MATERIALS AND METHODS This randomized clinical trail was conducted at a selective teaching hospital in Isfahan, Iran in 2012. The intervention consisted of four weekly multimedia training sessions of 2 h that included education and family support for 50 family caregivers. Caregiver burden was measured using the Zarit Burden Interview (ZBI). Paired t-test, Student's t-tests, and repeated measures analysis of variance (ANOVA) were used to test for significant differences of the mean scores of burden between the intervention and control groups over a 3-month period. RESULTS The intervention was successful in reducing caregiver burden over time both at the end of the intervention period (P = 0.000) and 3 months after the intervention (P = 0.000). CONCLUSIONS Nurses and other healthcare providers can use the findings of this study in order to implement effective programs to reduce family caregivers' challenges and to provide them more support

Caregiver burden among Iranian heart failure family caregivers: A descriptive, exploratory, qualitative study

Background: Living with patients of chronic diseases such as heart failure (HF) is a diffi cult situation for the caregivers. This study explored the Iranian family caregivers’ burden of caregiving for patients with HF. Materials and Methods: Eighteen family caregivers of the HF patients from two governmental medical training centers in Isfahan, Iran were recruited using purposive sampling. Data were collected through face-to-face semi-structured interviews. Each interview was transcribed verbatim and was thematically analyzed concurrently. Results: Four major themes emerged from the analysis of the transcripts: Lack of care-related knowledge, physical exhaustion, psychosocial exhaustion, and lack of support. Family caregivers believed that they have little knowledge about the patients’ disease, drugs, and how to perform caregiving roles. They experienced negative physical and psychosocial consequences of full-time and highly extended caregiving roles, such as musculoskeletal disorder, fatigue, and sleep disturbance, and a high level of anxiety, stress, and social isolation. Caregivers believed that they receive little familial and organizational support on the emotional and fi nancial dimensions of caregiving. Conclusions: The fi ndings of this study can be used by healthcare providers, especially nurses, to provide more effective social, informational, and professional support for family caregivers