Energy Resolution from a Silicon Detector's Interstrip Regions.

In this work, we present a novel approach for improving the energy resolution from particles impinging on the interstrip regions of silicon strip detectors. We employed three double-sided strip detectors from the GRIT array and a triple α-source under laboratory conditions. The results showed that the interstrip resolution depends not only on the impinging side but also on whether it is a P- or an N-interstrip. We obtained the interstrip energy resolution down to 0.4%, and, depending on the scenario, the resolution was enhanced by a factor of 2. We believe that this new rotation method allows for the possibility of applying particle identification methods on interstrip events, which in most cases are dismissed during data recording.

Test Bench for Highly Segmented GRIT Double-Sided Silicon Strip Detectors: A Detector Quality Control Protocol.

This work deals with the characteristics of highly segmented double-sided silicon detectors. These are fundamental parts in many new state-of-the-art particle detection systems, and therefore they must perform optimally. We propose a test bench that can handle 256 electronic channels with off-the-shelf equipment, as well as a detector quality control protocol to ensure that the detectors meet the requirements. Detectors with a large number of strips bring new technological challenges and issues that need to be carefully monitored and understood. One of the standard 500 µm thick detectors of the GRIT array was investigated, undergoing studies that revealed its IV curve, charge collection efficiency, and energy resolution. From the data obtained, we calculated, among other things, the depletion voltage (110 V), the resistivity of the bulk material (9 kΩ·cm), and the electronic noise contribution (8 keV). We present, for the first time, a methodology called "the energy triangle'' to visualize the effect of charge sharing between two adjacent strips and to study the hit distribution with the interstrip-to-strip hit ratio (ISR).

Towards the Limits of Existence of Nuclear Structure: Observation and First Spectroscopy of the Isotope

The most remote isotope from the proton dripline (by 4 atomic mass units) has been observed: ^{31}K. It is unbound with respect to three-proton (3p) emission, and its decays have been detected in flight by measuring the trajectories of all decay products using microstrip detectors. The 3p emission processes have been studied by the means of angular correlations of ^{28}S+3p and the respective decay vertices. The energies of the previously unknown ground and excited states of ^{31}K have been determined. This provides its 3p separation energy value S_{3p} of -4.6(2) MeV. Upper half-life limits of 10 ps of the observed ^{31}K states have been derived from distributions of the measured decay vertices.

Origin of enhancement in Raman scattering from Ag-dressed carbon-nanotube antennas: experiment and modelling.

The D- and G-band Raman signals from random arrays of vertically aligned, multi-walled carbon nanotubes are significantly enhanced (up to ∼14×) while the signal from the underlying Si substrate is simultaneously attenuated (up to ∼6×) when the nanotubes are dressed, either capped or coated, with Ag. These Ag-induced counter-changes originate with the difference in geometry of the nanotubes and planar Si substrate and contrast in the Ag depositions on the substrate (essentially thin film) and the nanotube (nano-particulate). The surface integral equation technique is used to perform detailed modelling of the electromagnetic response of the system in a computationally efficient manner. Within the modelling the overall antenna response of the Ag-dressed nanotubes is shown to underpin the main contribution to enhancement of the nanotube Raman signal with hot-spots between the Ag nanoparticles making a subsidiary contribution on account of their relatively weak penetration into the nanotube walls. Although additional hot-spot activity likely accounts for a shortfall in modelling relative to experiment it is nonetheless the case that the significant antenna-driven enhancement stands in marked contrast to the hot-spot dominated enhancement of the Raman spectra from molecules adsorbed on the same Ag-dressed structures. The Ag-dressing procedure for amplifying the nanotube Raman output not only allows for ready characterisation of individual nanotubes, but also evidences a small peak at ∼1150 cm-1 (not visible for the bare, undressed nanotube) which is suggested to be due to the presence of trans-polyacetylene in the structures.

Diamond detector for alpha-particle spectrometry.

An artificially grown high purity diamond was used as a detector for alpha-particle spectrometry. Diamond detectors can match the performance of silicon detectors employed in standard continuous air monitoring systems. Its radiation hardness and electronic properties make them ideal to work under extreme condition such as high temperature and ambient lights. A 50 µm thickness single-crystal diamond detector has been compared with a 300 µm passivated implanted planar silicon detector, under ambient conditions.

[Percutaneous microtenotomy and platelet rich plasma for epicondylitis]. / Microtenotomía percutánea y plasma rico en plaquetas para epicondilitis.

UNLABELLED: Epicondylitis is common in young patients and athletes. It is usually addressed with uneffective or very aggressive treatments. Due to the recurrence of the condition and the disability it causes its management is very demanding. METHODS: Five patients ages 30-45 years with diagnosis of epicondylitis were treated and followed-up. An outpatient procedure was performed under general anesthesia consisting of percutaneous release of the annular ligament and injection of 5cc of platelet rich plasma from the patient following the centrifugation of a blood sample. Following the injection the patient was referred to physical therapy and rehabilitation with a specific program consisting of isotonic exercises aimed at muscle strengthening. RESULTS: At the two-week follow-up, important subsidence of symptoms was reported, with full ranges of motion, intact muscle strength, and full resumption of daily life and sports activities. CONCLUSIONS: This alternative method is a good and not very invasive option for patients with epicondylitis, and it may help avoid surgical treatment. An appropriate rehabilitation program contributes to optimize the results and helps patients return sooner to their activities of daily living.

Combined antenna and localized plasmon resonance in Raman scattering from random arrays of silver-coated, vertically aligned multiwalled carbon nanotubes.

The electric field enhancement associated with detailed structure within novel optical antenna nanostructures is modeled using the surface integral equation technique in the context of surface-enhanced Raman scattering (SERS). The antennae comprise random arrays of vertically aligned, multiwalled carbon nanotubes dressed with highly granular Ag. Different types of "hot-spot" underpinning the SERS are identified, but contrasting characteristics are revealed. Those at the outer edges of the Ag grains are antenna driven with field enhancement amplified in antenna antinodes while intergrain hotspots are largely independent of antenna activity. Hot-spots between the tops of antennae leaning towards each other also appear to benefit from antenna amplification.

[The most frequent organisms in open fractures in Mexico]. / Microorganismos más frecuentes en fracturas expuestas en México.

UNLABELLED: An open fracture is one in which the bone segments penetrate into the skin leaving the bone in contact with the outer environment. Many microorganisms may cause wound infection in open fractures; the most common one is Staphyloccocus aureus. METHODS: This study included a group of 75 patients of both genders seen from November 1st, 2009 to April 30, 2010. A sample for culture was taken upon admission and incubated for 48 hours. RESULTS: A total of 75 patients were included, 62 males and 13 females. The age range was 18 to 83 years. The tibia and the fibula were the most commonly affected bones. The most common mechanisms of injury resulted from high energy. The most frequent grade of exposure was III B. Forty-six percent of the culture results were negative at 48 hours; the most frequent organisms found in the positive cultures were Staphylococcus aureus and Candida albicans. CONCLUSIONS: Males are the gender most affected by open fractures. This kind of condition occurs at productive ages. The time elapsed between the injury and the onset of treatment was significant. The culture results showed that the most frequent organism was Staphylococcus aureus, together with Candida albicans.

[Treatment of pediatric humeral supracondylar fractures with a lateral external fixator. A case report]. / Tratamiento con fijador externo lateral en pacientes pediátricos con fracturas supracondíleas humeral. Reporte de un caso.

We present the case of a child with a Gartland III humeral supracondylar fracture treated with a lateral external fixator and 1.6 mm Kirschner nails. The edema and postoperative pain subsided and the patient had early mobility, thus avoiding the use of cast immobilization. The patient was discharged with elbow mobility and no complications. Follow-up was conducted at weeks 1, 3, 6, 8, 12 and 16 with favorable results. The outcome was early mobility and the resulting shorter rehabilitation period, as well as better management of the skin and soft tissues, decreased muscle hypotrophy and appropriate healing.