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A giant magnetocaloric effect induced by sodium-deficiency in a La0.8Na0.2-x□xMnO3 (0.00 ≤ x ≤ 0.15) polycrystalline sample is reported in the present research work. The ability to tune the temperature transition close to room temperature is revealed to be possible by changing the sodium-deficiency content as well. All samples were synthesized using solid-solid reaction. X-ray diffraction and magnetization measurements were performed to investigate their crystallographic structure and magnetocaloric properties. A rhombohedral structure with the R3[combining macron]c space group is deduced from pattern diffraction refinement of all samples. A second-order magnetic phase transition from the ferromagnetic to the paramagnetic state at the Curie temperature (Tc) is observed. Such a Tc decreased from 335 to 260 K when the sodium deficiency rate increased. Besides, the magnetic entropy change and the related Relative Cooling Power (RCP) values, sensitive to sodium-deficiency, were estimated. The magnetic entropy change ranges increased from 2.38 J kg(-1) K(-1) to 3.48 J kg(-1) K(-1) under a magnetic field of 2 T, whereas the RCP varied from 210 to 235 J kg(-1) under an applied magnetic field of 5 T, when x increased from 0.00 to 0.15. The comparison of the values reported in the reference Gd material underlines that the proposed oxide material has substantial advantages for magnetic refrigeration.

Introduction: An investigation of emergency department (ED) poisonings was conducted to characterize poisoning demographics and evaluate correlations with select co-morbidities., Methods: The study population evaluated consisted of 649 poisoning cases admitted between 2004 and 2007 to an inner-city, level 1 emergency department., Results: Ethnicity, age, and gender had a substantial impact on the population distribution as poisoning cases were predominantly African Americans (79.9%) between 36 and 45 years old with a 1:3 male to female ratio. Intentional illicit drug overdose was the most prevalent cause of poisoning, heroin being the most frequent substance found in 35.4% ( n = 230) of cases, followed by cocaine overdose at 31.7% ( n = 206), concomitant heroin and cocaine overdose at 4.3% ( n = 28), multiple drug poisoning at 5.5% ( n = 36), and antidepressant/antipsychotic poisoning at 6% ( n = 39). Significant correlations were found between heroin poisoning and asthma (F = 20.29, DF = 1, P = 0.0001), cocaine poisoning and hypertension (F = 33.34, DF = 1, P = 0.0001), and cocaine poisoning and cardiovascular disease (F = 35.34, DF = 1, P = 0.0001). A change in the pattern of illicit drug use from injection to inhalation was detected and the resulting increase of inhalation and insufflation of illicit substances may partially explain the correlation found between heroin use and asthma., Conclusions: These results provide supporting evidence that deliberate poisoning with illicit drugs remains a serious healthcare issue that significantly aggravates co-morbidities and raises treatment costs by increasing both the rate of hospitalization and hospital length of stay.

Titan, the largest satellite of Saturn, has a dense N2-CH4 atmosphere rich in organic compounds, both in gas and in aerosol phases. Its surface is probably covered by oceans of liquid methane-ethane mixtures, with many dissolved organics. This quasi planet appears as a natural laboratory to study chemical evolution toward complex organic systems in a planetary environment over a long time scale. With the Cassini-Huygens mission NASA and ESA will jointly send an orbiter (Cassini) around Saturn and a probe (Huygens) in the atmosphere of Titan. This mission, currently planned to be launched in 1996-1997 for a Saturn - Titan arrival in 2004, offers a unique opportunity to study in detail extra-terrestrial organic processes. Consequently, it has important implications in the field of exobiology and the origins of life.