Aqueous solutions of polyoxometalates (POMs) have been shown to have potential as high-capacity energy storage materials due to their potential for multi-electron redox processes, yet the mechanism of reduction and practical limits are currently unknown. Herein, we explore the mechanism of multi-electron redox processes that allow the highly reduced POM clusters of the form {MO} to absorb electrons in aqueous solution, focusing mechanistically on the Wells-Dawson structure X[PWO], which comprises 18 metal centers and can uptake up to 18 electrons reversibly ( = 18) per cluster in aqueous solution when the countercations are . This unconventional redox activity is rationalized by density functional theory, molecular dynamics simulations, UV-vis, electron paramagnetic resonance spectroscopy, and small-angle X-ray scattering spectra.
View Article and Find Full Text PDFChecklists can improve adherence to standardized procedures and minimize human error. We aimed to test if implementation of a checklist was feasible and effective in enhancing patient care in an emergency department handling internal medicine cases. We developed four critical event checklists and confronted volunteer teams with a series of four simulated emergency scenarios.
View Article and Find Full Text PDFA family of six polyoxometalate-based magnetic compounds were synthesized by anchoring N-oxide type TEMPO radicals onto an Anderson type polyoxometalate cluster. The complexes were structurally characterised by single crystal X-ray diffraction and the intramolecular paramagnetic interactions between TEMPO radicals and Mn ions of the resulting hybrids were investigated in detail by electron paramagnetic resonance and the Evans NMR method.
View Article and Find Full Text PDFStandard procedures and guidelines provide specific instructions for basic and advanced cardiac life support. Recommendations for the admission of patients from preclinical into clinical structures after successful cardiopulmonary resuscitation (CPR) are available, but only a few are detailed. In the presence of ST-elevation myocardial infarction after return of spontaneous circulation (ROSC), coronary angiography must be performed as soon as possible.
View Article and Find Full Text PDFImportance: Therapeutic hypothermia may increase survival with good neurologic outcome after cardiac arrest. Trans-nasal evaporative cooling is a method used to induce cooling, primarily of the brain, during cardiopulmonary resuscitation (ie, intra-arrest).
Objective: To determine whether prehospital trans-nasal evaporative intra-arrest cooling improves survival with good neurologic outcome compared with cooling initiated after hospital arrival.
The aims of this study are (1) to assess changes in infant WHO growth indicators (weight-for-age, weight-for-length, and head circumference z-scores) from birth to 12 months of age as a function of feeding practices (FP) and (2) to describe the proportion of infants experiencing rapid weight gain (RWG; defined as change in weight-for-age z-score of ≥0.67 between birth and six months) among different FP. The modified Infant Feeding Practices Study II questionnaire was administered to 149 diverse caretakers/mothers of infants who were less than six months of age in a pediatric outpatient clinic.
View Article and Find Full Text PDFBackground: Delirium is frequent in elderly patients presenting in the emergency department (ED). Despite the severe prognosis, the majority of delirium cases remain undetected by emergency physicians (EPs). At the time of our study there was no valid delirium screening tool available for EDs in German-speaking regions.
View Article and Find Full Text PDFDtsch Med Wochenschr
February 2018
The use of Point-of-care ultrasonography (POC Ultrasonography) is getting more and more important in the bedside care of patients, especially in emergency- and intensive care units. In addition to the focused sonography of the heart, lungs and abdomen, the POC Ultrasonography recently includes also cases in prehospital care. Increasingly special applications in intensive care, e.
View Article and Find Full Text PDFBackground: During the last decade target temperature management has become an integral part of postresuscitation care. Within recent years there was a strong debate about the optimal target temperature, which might have effects on the preclinical induction of hypothermia. The present investigation focuses on the use of mild therapeutic hypothermia by emergency services in the state of Baden-Württemberg (Germany) and compares it to results of a prior study in 2008.
View Article and Find Full Text PDFWe report a {Cu} embedded within a {W} cluster containing four cubane-like [CuO] units within an isopolyoxotungstate (isoPOT) in a {NaCu[(HWO) (CHCOO)(OH)]}·88HO (1) and a polyanion Cu-linked {W} chain NaCu[(HWO)(CHCOO)(OH)]·26HO (2). Electronically, the redox properties show that both compounds 1 and 2 undergo irreversible reductions resulting in the demetalation of the compounds, whilst the magnetic behavior of 1 and 2 shows a weak antiferromagnetic and a stronger ferromagnetic coupling, respectively.
View Article and Find Full Text PDFPoint-of-care ultrasound in acute care medicine is a prerequisite for diagnosis and therapy monitoring of critically ill patients. There is currently no uniform education strategy for medical intensive care and emergency medicine. As part of the basic level, the trainee takes theoretical and clinical training covering abdominal and thoracic ultrasonography and focused cardiovascular ultrasound.
View Article and Find Full Text PDFBy incorporating phosphorus(III)-based anions into a polyoxometalate cage, a new type of tungsten-based unconventional Dawson-like cluster, [W18O56(HP(III)O3)2(H2O)2](8-), was isolated, in which the reaction of the two phosphite anions [HPO3](2-) within the {W18O56} cage could be followed spectroscopically. As well as full X-ray crystallographic analysis, we studied the reactivity of the cluster using both solution-state NMR spectroscopy and mass spectrometry. These techniques show that the cluster undergoes a structural rearrangement in solution whereby the {HPO3} moieties dimerize to form a weakly interacting (O3PH⋅⋅⋅HPO3) moiety.
View Article and Find Full Text PDFFlash memory devices--that is, non-volatile computer storage media that can be electrically erased and reprogrammed--are vital for portable electronics, but the scaling down of metal-oxide-semiconductor (MOS) flash memory to sizes of below ten nanometres per data cell presents challenges. Molecules have been proposed to replace MOS flash memory, but they suffer from low electrical conductivity, high resistance, low device yield, and finite thermal stability, limiting their integration into current MOS technologies. Although great advances have been made in the pursuit of molecule-based flash memory, there are a number of significant barriers to the realization of devices using conventional MOS technologies.
View Article and Find Full Text PDFWe explore the concept that the incorporation of polyoxometalates (POMs) into complementary metal oxide semiconductor (CMOS) technologies could offer a fundamentally better way to design and engineer new types of data storage devices, due to the enhanced electronic complementarity with SiO2, high redox potentials, and multiple redox states accessible to polyoxometalate clusters. To explore this we constructed a custom-built simulation domain bridge. Connecting DFT, for the quantum mechanical modelling part, and mesoscopic device modelling, confirms the theoretical basis for the proposed advantages of POMs in non-volatile molecular memories (NVMM) or flash-RAM.
View Article and Find Full Text PDFThe new tungstatoiodate, α-[H5W18O59(IO3)](6-), containing I(V)O3(-) within a {W18O54} metal oxide framework has been prepared and shown by X-ray crystallography and mass spectrometry to be derived from the fully oxidised [H3W18O56(IO6)](6-) by two-electron reduction accompanied by a redox-triggered structural rearrangement where three I-O covalent bonds are broken.
View Article and Find Full Text PDFNaphthoxanthenyl 1 is a new stable phenalenyl-type radical. Electrochemical studies indicate that 1 has two reversible redox processes that occur on comparatively short time scales. Crystals containing 1 can be grown by electrocrystallization, suggesting that they are conductive.
View Article and Find Full Text PDFThe synthesis of a series of discrete lanthanide-capped polyoxovanadate cages is presented along with magnetic and electrochemical measurements which reveal a redox active dodecavanadate cluster with potential as a new functional building unit in polyoxovanadate chemistry.
View Article and Find Full Text PDFTwo near isomeric clusters containing a novel {Mn(8)W(4)} Keggin cluster within a [W(36)Mn(10)Si(4)O(136)(OH)(4)(H(2)O)8](24-) cluster are reported: K(10)Li(14)[W(36)Si(4)O(136)Mn(II)(10)(OH)(4)(H(2)O)(8)] (1) and K(10)Li1(3.5)Mn(0.25)[W(36)Si(4)O(136)Mn(II)(10)(OH)(4)(H(2)O)(8) ] (1').
View Article and Find Full Text PDFWe show how an array of ion-sensitive-field-effect-transistors can be used to both spatially and temporally image the oscillating pH/ion waves produced by the Belousov-Zhabotinsky (BZ) reaction with high resolution.
View Article and Find Full Text PDFReal-time ion flux imaging: an ion-sensitive field-effect transistor (ISFET) array is coupled with optical microscopy to image the growth of, and ion flux through, micrometer-scale tubes and membranes built from polyoxometalate clusters. The correlation between the optical and ionic imaging data is excellent, showcasing the use of ISFET arrays for high-resolution spatial and temporal mapping of ionic movements.
View Article and Find Full Text PDFThe reaction of the hexacyanometalates K3[M(1)(CN)6] (M(1) = Cr(III), Fe(III), Co(III)) with the bispidine complexes [M(2)(L(1))(X)](n+) and [M(2)(L(2))(X)](n+) (M(2) = Mn(II), Ni(II), Cu(II); L(1) = 3-methyl-9-oxo-2,4-di-(2-pyridyl)-7-(2-pyridylmethyl)-3,7-diazabicyclo[3.3.1]nonane-1,5-dicarboxylic acid dimethyl ester; L(2) = 3-methyl-9-oxo-7-(2-pyridylmethyl)-2,4-di-(2-quinolyl)-3,7-diazabicyclo[3.
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