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Die suprakondylare Humerusfraktur ist eine typische Fraktur des Wachstumsalters. Ziel dieser Untersuchung war die Komplikationserfassung und die Evaluation der funktionellen Ergebnisse der im Katholischen Kinderkrankenhaus Wilhelmstift Hamburg operierten Kinder. Insgesamt 191 Patienten mit 194 dislozierten Frakturen wurden vom 1.7.2004–30.6.2009 operiert. Alle Frakturen wurden zeitnah am Unfalltag operiert und osteosynthetisch stabilisiert. Bei 17 Patienten (9%) war eine offene Reposition erforderlich. Eine Osteosynthese mit 2 gekreuzten Kirschner-Drahten erfolgte bei 92% der Patienten. Die Materialentfernung und Bewegungsfreigabe erfolgte nach 4 Wochen; 185 Patienten konnten mit einem Follow-up von 3 Monaten bis 3 Jahren nachuntersucht werden. Bei den Nachuntersuchungen wurden Beweglichkeit, Funktion, Nervenstatus und Achsenverhaltnisse kontrolliert. Bei 8 Patienten (4,3%) verblieb eine Fehlstellung in der Frontal- oder Sagittalebene zwischen 11–15°. Eine Indikation zur Korrekturosteotomie bestand bei strenger Indikationsstellung nicht. Nach dem Mayo Performance Score erzielten 182 Patienten (98,4%) die maximale Punktzahl. Traumatische Nervenschaden wurden bei 15 Patienten (8%) dokumentiert, iatrogene bei 6 Patienten(3%). Gefasinterventionen waren bei 5 Patienten (2,5%) erforderlich. Dislozierte instabile suprakondylare Humerusfrakturen sollten notfallmasig reponiert und stabilisiert werden. Mit der etablierten Kirschner-Draht-Osteosynthese werden gute Ergebnisse erzielt. Bei Trummerzonen sind verbleibende Fehlstellungen moglich. Iatrogene Nervenlasionen lassen sich durch Darstellung des N. ulnaris reduzieren. Moglicherweise kann die Komplikationsrate durch alternative Osteosynthese-Verfahren wie der elastischen stabilen intramedullaren Nagelung oder eines Fixateur externe weiter reduziert werden.

Introduction: Although the early defi nitive closure of gastroschisis is possible in many cases, there is an ongoing discussion about the advan- tages of staged reduction. Diff erent strategies and materials have been described to wrap the bowel for protection and reduce heat and fl uid loss. The variety of devices ranges from pros- thetic patches to biomaterials. We present use of the umbilical cord for temporary coverage in primarily irreducible gastroschisis. Method: After revision and reduction of as much gut as possible under constant monitoring of the bladder pressure, the remaining eviscer- ated intestine is covered by the longitudinally split umbilical cord. Over the following days the continued reduction of the bowel relies on grav- ity, assisted by progressive compression by the shrinking umbilical cord tissue. At 10 days after performing the umbilical cord fl ap, it is possible to close the fascia without complications using gentle pressure. Results: Since 1991 we have used this umbili- cal cord fl ap for staged reduction in 17 infants (10 females, 7 males) with giant gastroschisis. There were no complications related to use of the umbilical cord fl ap, no infections or NEC epi- sodes, and no mortality. Length of hospital stay was 5 weeks on average. In 3 patients the course was complicated by associated defects or an underlying malformation. Conclusion: Our experience confi rms the advantage of a staged reduction in giant gastro- schisis. The use of autogenic material such as the umbilical cord has advantages such as low infec- tion rates and easy availability.

π + and π − production cross sections for 800-MeV protons on C and Cu have been measured at laboratory angles of 0°, 3°, 5°, 7°, 10°, 15°, and 20°. Pions were analyzed using the High Resolution Proton Spectrometer (HRS) facility for momenta from 364 to 675 MeV/ c . Particle identification was made utilizing a time-of-flight method. We estimate the total systematic and statistical error to be ±15% for measurements at 0° and 3° and ±10% at other angles. These data have been used to determine the optimum energy and pion production angle for injection into a proposed superconducting accelerator for pions. Protons are the main source of contamination for a π + beam. Proton-to-pion ratios are given for laboratory angles of 5° and larger.

The conserved-vector-current hypothesis, together with measured nuclear-beta-decay rates, predicts a value of the rate for the decay ..pi../sup +/..--> pi../sup 0/e/sup +/..nu.. of 0.4027 +- 0.0018 s/sup -1/. With use of a decay-in-flight technique the authors have made the most precise measurement to date of this rate, obtaining the value 0.398 +- 0.015 s/sup -1/, in good agreement with the prediction.

A search has been performed for the muon-number--violating decay ..mu -->..e/sup +/e/sup +/e/sup -/. No candidate event has been found, the result yielding an upper limit for the branching ratio of B/sub mu3e/ ..e/sup +/e/sup +/e/sup -/..nu../sub e/nu-bar/sub ..mu../ events, eleven such events were observed. They agree in number and spectra with expectations based on standard electroweak theory.

A search with the Crystal Box detector shows no evidence for the lepton-family-number-nonconserving decays ..mu -->..e..gamma.., ..mu -->..e..gamma gamma.., or ..mu -->..eee. The search provides upper limits for the branching ratios of GAMMA(..mu -->..e..gamma..)/GAMMA(..mu -->..evv-italic-bar) ..e..gamma gamma..)/GAMMA(..mu -->..evv-italic-bar) ..eee)/GAMMA(..mu -->..evv-italic-bar)

We have analyzed 25 000 ${K}_{e3}$ decays, reconstructed to the center of mass by measurement of the ${{K}_{L}}^{0}$ momentum from time of flight and measurement of the $\ensuremath{\pi}$ and $e$ momenta with a spark-chamber-magnet spectrometer. Using the linear parametrization of the vector form factor ${f}_{+}({q}^{2})=1+{\ensuremath{\lambda}}_{+}(\frac{{q}^{2}}{{{m}_{\ensuremath{\pi}}}^{2}})$ we find ${\ensuremath{\lambda}}_{+}=0.0270\ifmmode\pm\else\textpm\fi{}0.0028$. Upper limits for the scalar (${f}_{s}$) and tensor (${f}_{t}$) form factors at the 68% confidence level are $\frac{{f}_{s}}{{f}_{+}}l0.04$, $\frac{{f}_{t}}{{f}_{+}}l0.23$, corresponding to intensity ratios $\frac{{I}_{s}}{{I}_{v}}=0.3%$ and $\frac{{I}_{t}}{{I}_{v}}l0.4%$.

The conserved-vector-current hypothesis, together with measured nuclear beta-decay rates, predicts a value of the rate for the decay ..pi../sup +/..--> pi../sup 0/e/sup +/..nu.. of 0.4027 +- 0.0018 s/sup -1/. Using a decay-in-flight technique we have made the most precise measurement to date of this rate, obtaining the value 0.394 +- 0.015 s/sup -1/, in good agreement with the prediction. This differs slightly from the value previously reported in W. K. McFarlane et al., Phys. Rev. Lett. 51, 249 (1983).

A search has been performed for the decays μ → eee, μ → e γ , and μ → eγγ with a sensitivity in the branching ratios at the level of 10 −10 . The experiment used a separated, 26 MeV/c μ + beam with an average intensity of 300kHz. A total of 2.2 × 10 11 muon decays were examined for the present result. The detector for the experiment Is the Crystal Box, which consists of a cylindrical drift chamber surrounded by 396 NaI(T1) crystals. A layer of scintillation counters in front of the crystals provided timing for electrons and a veto for photons. The energy resolution for electrons and photons is ≈6% (FWHM). The position resolution of the drift chamber is 350 μm leading to a vertex cut with a rejection of 10 3 for μ → eee. The timing resolution is ≈300 ps from the scintillators and ~1 ns from the crystals. No candidate for μ → eee has been found, yielding an upper limit for the branching ratio of B μ 3e −10 (90% C.L.).

An array of 49 NaI(Tl) modules each 20 inch in depth and 2.5 inch × 2.5 inch in cross section has been constructed and its properties, especially energy resolution, explored for positrons in the range 20 MeV – 18 GeV. A subsequent much larger detector, the Crystal Box, has also been constructed from 396 modules of the same cross section, but mostly 12 inch in depth, and operated as a γ-ray and positron detector in a search for rare muon decays. The calibration procedure used for the Crystal Box and its characteristic resolutions in energy, impact point and time are described.

A very low momentum, high purity positive muon beam has been developed at LAMPF, utilizing muons which originate from pion decays at rest in the target for the primary proton beam and are transported by the LAMPF stopped muon channel. The channel is tuned to transport muons with momenta as low as 3 MeV/c and hence selects muons originating some distance below the target surface (subsurface muons). A static E × B separator largely eliminates the e+ component in the beam.

The LAMPF high-energy pion channel was tuned by tracing individual particles through the channel using multiwire proportional counters. Beam spot sizes, divergences, dispersions, and correlations between angle, displacement, and momentum were measured and optimized in an on-line least-squares search. The results are compared to predictions made by the TRANSPORT computer code, and it is found that the experimental results are in agreement with computer calculations.

The inclusive cross sections, measured up to large values of effective mass ($\ensuremath{\equiv}\frac{{q}^{2}}{2\ensuremath{\nu}}$), are well fitted by $\frac{d\ensuremath{\sigma}}{{d}^{3}p}={B}_{x}\mathrm{exp}(\ensuremath{-}\frac{{\ensuremath{\alpha}}_{x}{p}^{2}}{2{m}_{x}})$. Values of ${B}_{x}$ and ${\ensuremath{\alpha}}_{x}$ are given for Be, C, Cu, and Ta at the incident proton energy of 600 MeV and for Ag, Ta, and Pt at 800 MeV. Extremely large $\frac{d}{p}$ and $\frac{t}{p}$ ratios and large $A$ and ${q}^{2}$ dependences of the relative cross sections are observed.

A search for the charge-conjugation-noninvariant decay ..pi../sup 0/..-->..3..gamma.. has been made using the Crystal Box of the Los Alamos Meson Physics Facility. No signal in excess of background was observed, resulting in a branching-ratio upper limit of 3.1 x 10/sup -8/ (90% C.L.). A new upper limit of 2 x 10/sup -8/ (90% C.L.) was also established for the allowed decay ..pi../sup 0/..-->..4..gamma...

This Letter reports a new experimental search for the family-number-nonconserving decay ..mu../sup +/ ..-->.. e/sup +/..gamma... There is no evidence for the presence of this decay mode. The upper limit for the branching ratio is GAMMA(..mu.. ..-->.. e..gamma..)/GAMMA(..mu.. ..-->.. enu anti nu) < 4.9 x 10/sup -11/ (90% C.L.). 13 refs., 3 figs.

A new search for three-photon decays of the neutral pion has been made. No signal in excess of background was observed. The upper limit for the ..pi../sup 0/ ..-->.. 3..gamma.. branching ratio is 3.8 x 10/sup -7/ (90% confidence level).

Use has been made of backward (180degree) elastic scattering of 600 and 800 MeV protons as the experimental tool to search for the presence of nuclear states of very high binding energy, suggested by Feenberg and Primakoff and by Lee and Wick. This method, tested on a variety of targets, found no evidence for condensed nuclei (of 100 mb cross section) at a level of 10$sup -8$ per target nucleus. (AIP)

A new experimental search with the Crystal Box detector shows no evidence for the lepton-family-number--nonconserving decay ..mu../sup +/..-->..e/sup +/..gamma gamma... This corresponds to an upper limit for the branching ratio of GAMMA(..mu -->..e..gamma gamma..)/GAMMA(..mu -->..e..nu..nu-bar)

Muon rates and polarizations have been measured on several beam channels at LAMPF to characterize muon production from the primary target surface or adjacent volume. To produce these "surface" or "cloud" beams, the channel is tuned to accept beam directly from the target. The measurements range from 20-200 MeV/c in muon momentum at production angles of 20, 45, and 65°. Both ?+ and ?- rates, and ?+ polarization were measured. Surface beam polarization is close to 100%, while cloud beam polarization is low. The surface ?+ rate dependence upon proton beam depth in the target was studied.

A precise measurement of the differential cross section at zero degrees for the pion charge-exchange reaction ..pi../sup -/p ..-->.. ..pi../sup 0/n at p/sub ..pi../ = 522 MeV/c has been made. The result is dsigma/d/OMEGA(0/sup 0/) = 4.32 +- 0.11 mb/sr. 12 references.

New experimental upper limits for the branching ratios of the lepton‐family‐number nonconserving decays μ+ → e+γ and μ+ → e+γγ are presented. A new determination of γ, the ratio of pion axial‐vector to vector form factors, from radiative pion decay is also reported. These results are from data taken with the Crystal Box detector at LAMPF.

A search has been performed for the decays μ → eee, μ → eγ, and μ → eγγ with a sensitivity in the branching ratios at the level of 10−10. The experiment used a surface muon beam at LAMPF with an average intensity of 300 kHz. A total of ≳1011 muon decays was examined for the present result. The detector for the experiment is the Crystal Box which consists of a cylindrical drift chamber surrounded by 396 NaI(T1) crystals. A layer of scintillation counters in front of the crystals provided timing for electrons and a veto for photons. The energy resolution for electrons and photons is ∼6% (FWHM). The position resolution of the drift chamber is 350 μm leading to a vertex cut with a rejection of 103 for μ → eee. The timing resolution is ∼400 ps from the scintillators and ∼1 ns from the crystals. From these values, the eee and eγγ limits are expected to be background free.

Development of the Crystal Box Spectrometer at the Clinton P. Anderson Meson Physics Facility in Los Alamos has been completed. And a search for the rare muon decays mu to e−gamma, to e−2gamma, and to 3e is ready to start taking data. (AIP)