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Notes: A study has been made of the vibrational energy flow mechanisms and time scales pertaining to the overtone stretch excitations of methyl and acetylenic CH stretches in propyne. Classical trajectories are used to interpret the experimental data for the overtone linewidths, as well as to analyze the role that individual modes play in determining energy flow. The full anharmonic potential surface for these calculations, including all modes, has been developed from spectroscopic and structural information, including the linewidth data. The principal results are: (1) The trajectory calculations show a localization transition, corresponding to a switch over from normal-mode behavior for CH3 excitations up to v≅3 to a local-mode CH excitation within the CH3 moiety for excitations of v(approximately-greater-than)6, with transition behavior for v=4,5. (2) The acetylenic CH shows local-mode behavior from v=1. Extremely long lifetimes are found for the excitations of this mode, and the trajectories indicate that the experimental width is predominantly rotational. (3) The rocking and deformation modes are dominant receiving modes in the relaxation of the methyl stretch. (4) A shorter lifetime is calculated for the v=6 vs the v=5 or v=7 overtones of the methyl C–H stretch. Experimental results are qualitatively consistent with this prediction. The origin of this shorter lifetime is a band of resonances between the stretch excitation and combinations of rocking, deformation, and pseudorotation modes. (5) CH3 internal rotation figures importantly in the relaxation of some levels (v=5, 8 of CH3) where it "closes the energy gap'' for achieving resonant energy transfer. (6) For v=8 of the methyl CH, some direct energy transfer to both C–C(Triple Bond)C stretching modes is seen. The switching on of the stretches as receiving modes is a consequence of sufficiently strong interactions between the excited H and the C–C(Triple Bond)C chain, which take place at these high vibrational energies. (7) Evidence is found for long distance "through-space'' energy transfer due to long-range dipole–dipole forces. This transfer occurs from the acetylenic to the methyl CH stretches. This result is illustrated for the v=2 excitation of the acetylenichydrogen, and constitutes a direct demonstration of intramolecular long-distance, through-space v–v energy transfer. These results demonstrate the potential importance of large amplitude modes such as rocking and deformation as initial receiving modes for vibrational energy from excited CH overtones. On the time scale probed here (∼1 ps), despite the availability of many degrees of freedom, the transfer process is dominated by specific energy transfer channels and by the specific behavior of individual modes, rather than by statistical considerations, which will certainly prevail on longer time scales.

Notes: The vibrational overtone spectra of the acetylenic and methyl C–H stretches of propyne were obtained for the v=1 to v=6 and v=1 to v=7 levels, respectively. Propyne-dl was also studied and the methyl C–H stretching overtones were measured from v=1 to the v=7 level. The C–D stretch was observed only in the fundamental and first overtone regions. Lower level overtones were obtained by standard infrared techniques, while higher absorptions (〉12 000 cm−1) were obtained by intracavity dye laser photoacoustic spectroscopy. The C–H stretches in both molecules were analyzed in terms of the local-mode model, and harmonic frequencies (ωi) and anharmonicities (Xii) were calculated. In propyne these values were (acetylenic C–H stretch) ω1=3384±5 cm−1 and X11=−50±1 cm−1 and (methyl C–H stretch) ωm =3037±5 cm−1 and Xmm =−65±2 cm−1. In propyne-dl the methyl C–H stretch parameters were ωm =3034±5 cm−1 and Xmm =−64±2 cm−1. For propyne, a hot band (ν9→ν9+vν1) accompanying the acetylenic C–H stretch was observed for v=1–6 and the anharmonic interaction constant (X19=−23±7 cm−1) was calculated. A crossover from normal- to local-mode behavior has been observed for the methyl C–H stretches in propyne and propyne-dl at the v=3 and 4 levels. Below v=3 the symmetric and antisymmetric methyl C–H stretches are designated by the usual normal-mode notation (ν2 and ν6 in propyne; ν1 and ν6 in propyne-dl), while for v≥3 the single observed band is designated as a "methyl'' C–H stretch, vνm. Peak absorption cross sections have been measured for Δv1=1–5, Δvm =3–5, Δv2=1 and 2, and the parallel component of 2ν6 in propyne, and for Δv2=1 and 2, Δv1=1 and 2, Δvm =3 and 4, and the parallel component of 2ν6 in propyne-dl. During the course of this work the spectral constants of 3,3,3-trifluoropropyne were redetermined. The harmonic frequency ω1 is 3376±6 cm−1, the anharmonicityX11 is −49±1 cm−1, and the anharmonic interaction constant X17 is −17±6 cm−1.

Notes: In view of an increasing tendency in prosthetic management of haemophilic arthropathy, we intended to evaluate the efficacy of corrective osteotomy of the hip, specifically taking long-term clinical and radiographic results into consideration. Eleven hips affected by haemarthropathy in nine patients suffering from severe haemophilia A were treated with an intertrochanteric varus osteotomy. The average follow-up period was 15·4 years. The preoperative clinical score of the Advisory Committee of the World Federation of Haemophilia was 5·3 points (range 4–7) and the Pettersson score was 6·4 points (range 2–10). The average WFH score at follow-up had increased to 3·6 points. Seven hips showed clinical improvement, two hips showed a postoperative deterioration while a further two hips remained unchanged. The Petterson score increased to an average of 7·7 points. Here the radiographs of six patients indicated postoperative deterioration, three remained unaltered and two showed improvement. Our study cannot conclusively answer whether intertrochanteric varus osteotomy for haemophilic arthropathy of the hip is always a feasible alternative to joint arthroplasty. The decision for or against this procedure must be individually assessed and the patient must be thoroughly informed about the advantages and disadvantages of both procedures.

Notes: The in vitro stability of porcine factor VIII (PF VIII) was evaluated when it was reconstituted with sterile water (PF VIIISW) to ≈ 30 U PFVIII mL−1, as per the manufacturer’s recommendations, and stored in plastic syringes at room temperature, with and without heparin and at four different dilutions. PF VIII was prepared antiseptically without laminar airflow and remained sterile at room temperature for 1 week. PF VIIISW retained at least 88% of baseline activity for 48 h and 74–86% for 72 h. Addition of heparin 1 unit mL−1 solution resulted in a decrease in the stability of PF VIIISW to 72–74 % of baseline values by 24 h. Reconstituted PF VIIISW, further diluted with normal saline to 10–24 U PF VIII mL−1, retained 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:13518216:HAE114:ges" location="ges.gif"/〉 98% of baseline activity for 48 h and 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:13518216:HAE114:ges" location="ges.gif"/〉 84% of baseline for 72 h. PF VIII diluted to 6 U mL−1, however, retained 100% baseline activity for only 24 h, and declined to 71% and 64 % of baseline by 48 and 72 h, respectively. PF VIII reconstituted with normal saline, instead of sterile water, retained 90% or more of baseline activity for a minimum of 4 days. Once reconstituted, PF VIII appeared to be more stable at room temperature than when stored in the refrigerator.These in vitro stability studies confirm that PF VIII (30 U mL−1) can be given effectively by prolonged continuous infusion, since it retains 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:13518216:HAE114:ges" location="ges.gif"/〉 88% baseline activity at room temperature in a plastic syringe for a minimum of 48 h, remains sterile and will maintain baseline PF VIII levels when further diluted with saline.

Notes: Summary.  In this study the long-term value of corrective osteotomy around the knee was evaluated by means of clinical and radiographic parameters. Between 1974 and 1984 we performed 52 corrective osteotomies in the vicinity of the knee on patients affected by haemophilic arthropathy. Forty-two patients (45 osteotomies) were adequately followed-up at an average 11.6 years postoperatively. Using the clinical score of the Advisory Committee of the World Federation of Haemophilia, 38 patients showed a postoperative improvement, five remained clinically unchanged and two showed deterioration. Range of motion of the knee joint did not significantly improve postoperatively. The radiographic Pettersson score showed only a marginal decrease by an average 0.003 points at the time of follow-up. Only one patient needed subsequent joint replacement of both knees, on the left side 13 years after osteotomy and on the right side 8 years after osteotomy.Even in cases of marked radiographic joint destruction, corrective osteotomy shows acceptable long-term clinical results, underlining the feasibility of this management option in the treatment of haemophilic arthropathy of the knee. Although moderate cartilage degenerations in the femoropatellar complex and in the contralateral compartment can be tolerated, this therapy should primarily be contemplated for those patients where damage is unicompartmental and a corresponding axial deviation is found. Particularly the younger patient can benefit from this treatment option in that joint replacement may possibly wholly be avoided or at least postponed to a later stage of life.