Photon bunching in cathodoluminescence induced by indirect electron excitation.

The impulsive excitation of ensembles of excitons or color centers by a high-energy electron beam results in the observation of photon bunching in the second-order correlation function of the cathodoluminescence generated by those emitters. Photon bunching in cathodoluminescence microscopy can be used to resolve the excited-state dynamics and the excitation and emission efficiency of nanoscale materials, and it can be used to probe interactions between emitters and nanophotonic cavities. Unfortunately, the required integration times for these measurements can be problematic for beam-sensitive materials. Here, we report substantial changes in the measured bunching induced by indirect electron interactions (with indirect electron excitation inducing g2(0) values approaching 104). This result is critical to the interpretation of g2(τ) in cathodoluminescence microscopies, and, more importantly, it provides a foundation for the nanoscale characterization of optical properties in beam-sensitive materials.

Simple and effective suspension technique for laparoscopic cholecystectomy.

Many surgeons elect to dispense with the lateral retraction port during laparoscopic cholecystectomy using the American four-port technique; however, this may not be easy and safe. To retain the superior ergonomical and observation advantages, suspension techniques that leave virtually no scars have been developed to substitute for the lateral retraction port. All published techniques for suspending the gall bladder fundus were reviewed and an attempt was made to evolve a technique that is expedient, safe and cost-effective. In our setting, the optimal technique is to pass a folded thread down a 14-G intravenous cannula that has punctured the abdominal wall to form a snare loop to entrap and hold the gall bladder fundus. The anchorage is maintained by a two-haemostat technique heretofore undescribed. In some of the cases where better exposure of the undersurface of the liver is needed, the cannula can be directed to puncture the thoracic cage at or below the seventh intercostal space to provide cephalad retraction and to rotate the liver superiorly. Postoperative chest radiographs did not show any pneumothorax. The simple suspension technique emulates the four-port technique's advantages in terms of favourable ergonomics and exposure (and hence safety). It is suitable for selected patients and due caution should be exercised.

A case of small spigelian hernias successfully treated by a simple laparoscopy-assisted technique.

Clinical diagnosis and location of spigelian hernias is notoriously difficult, and the recommended repair techniques are many and varied. This report describes a case of ipsilateral double spigelian hernias treated by a laparoscopy-assisted technique hitherto undescribed. Suturing of the fascial defect was aided by a 14-gauge angiocatheter that had traversed the full thickness of the abdominal wall firstly on one side of the hernial defect under laparoscopic guidance. A strong suture was threaded down the angiocatheter sheath. Its intra-abdominal end was made to traverse the other side of the defect and resurface upon withdrawal of a snare loop made of a folded suture inserted through the angiocatheter after the latter had been redirected to puncture the opposite edge. The knot was tied extracorporeally. This technique provides the benefits of laparoscopic localization to be combined with the advantages derived from the novel use of an angiocatheter--simplicity, low cost, safety, minimized tissue trauma, and improved cosmesis. It is therefore recommended for selected cases of small spigelian hernias.