Derivation of the respiratory rate signal from a single lead ECG

It has been long established that respiration has an influence on heart rate, and this effect is called respiratory sinus arrhythmia. As a result, two inferences can be postulated: first respiration information can be derived from cardiac activity, and second this effect offers the potential of removing the respiration effect that suppresses cardiac information which is of clinical significance. As a result of research performed at NJIT, there is a significant amount of data on exercise and heart rate recovery, but not the associated respiration signal. The motivation of this research was to compare and implement an optimal ECG derived respiration program, develop an adaptive peak detector algorithm to process the complex respiration signal and produce a usable respiration rate waveform. Three methods for deriving respiration from a single lead ECG were identified and implemented in LabVIEW. The three methods were R wave amplitude modulation (RWA), R wave duration (RWD), and the multiplication of RWA and RWD signals. Data analysis was carried out by comparing actual paced breathed respiration signal with lead I ECG derived respiration of ten normal subjects. The data analysis suggests that RWA is the best method with a correlation of 0.95. Then an algorithm to derive a continuous respiration rate signal from actual respiration signal with a high level of accuracy was developed. As a result of this research a program has been developed which provides respiratory information of clinical significance from ordinary single lead ECG for situations in which ECG but respiration is not routinely monitored

Microencapsulation of Diclofenac Sodium by Nonsolvent Addition Technique

Purpose: To prepare, using non-solvent addition technique, diclofenac sodium-ethylcellulose microparticles with modified drug release properties.Methods: Microparticles were prepared by non-solvent addition phase separation method and characterized by micromeritics, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), dissolution test and thermal analysis.Results: The microparticles were whitish, irregular, aggregated, and in the size range of 390 - 442 μm size. Drug embedment efficiency was 89 - 91 %. Characterisation studies indicate that there was no strong chemical interaction between the drug and the polymer in the microparticles. Polymer concentration and sustained release behavior were directly proportional.Conclusion: Non-solvent addition phase separation is a suitable method for preparing diclofenac sodium-ethylcellulose multi-unit controlled release drug delivery system.Keywords: Phase separation, Diclofenac sodium, Ethylcellulose, Non-solvent addition, Characterisation

1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-aminium chloride–thio­urea (1/1)

In the title compound, C11H14N3O+·Cl−·CH4N2S, the components are connected into a two-dimensional polymeric structure parallel to (001) via N—H⋯Cl, N—H⋯O, N—H⋯S and C—H⋯S hydrogen bonds. The dihedral angle between the phenyl and 2,3-dihydro-1H-pyrazole rings is 44.96 (7)°

2-Benzoyl-1,1-diethyl-3-phenyl­guanidine

In the title tetrasubstituted guanidine, C18H21N3O, the guanidine and carbonyl groups are not coplanar, as reflected by the torsion angles involving the N=C atoms [17.6 (3), −141.68 (17) and 42.2 (3)°]. This is probably due to the absence of an intra­molecular N—H⋯O hydrogen bond, forming a six-membered ring, and is commonly observed in this class of compounds. In the crystal structure, centrosymmetric dimers are formed via pairs of inter­molecular N—H⋯O hydrogen bonds. The dihedral angles between the guanidine plane and the phenyl ring and benzoyl plane are38.06 (9) and 41.54 (7)°, respectively