Standard Auctions with Identity Dependent Externalities

We analyze equilibrium bidding behavior in a three bidder open ascending bid auction with identity dependent externalities. We prove the existence of a unique symmetric equilibrium and then show that for sufficiently large externalities, the open auction yields strictly higher expected revenues compared to a sealed bid auction. An open auction reveals to bidders more payoff relevant information than a sealed bid auction and as a consequence, bidders are shown to have a higher willingness to pay in the early rounds of an open auction. The open auction is also shown to be more efficient than the sealed bid auction.

A novel receive-only liquid nitrogen (LN2)-cooled RF coil for high-resolution in vivo imaging on a 3-Tesla whole-body scanner

The design and operation of a receive-only liquid nitrogen (LN2)-cooled coil and cryostat suitable for medical imaging on a 3-T whole-body magnetic resonance scanner is presented. The coil size, optimized for murine imaging, was determined by using electromagnetic (EM) simulations. This process is therefore easier and more cost effective than building a range of coils. A nonmagnetic cryostat suitable for small-animal imaging was developed having good vacuum and cryogenic temperature performance. The LN2-cooled probe had an active detuning circuit allowing the use with the scanner's built-in body coil. External tuning and matching was adopted to allow for changes to the coil due to temperature and loading. The performance of the probe was evaluated by comparison of signal-to-noise ratio (SNR) with the same radio-frequency RF) coil operating at room temperature (RT). The performance of the RF coil at RT was also benchmarked against a commercial surface coil with a similar dimension to ensure a fair SNR comparison. The cryogenic coil achieved a 1.6- to twofold SNR gain for several different medical imaging applications: For mouse-brain imaging, a 100-mu m resolution was achieved in an imaging time of 3.5 min with an SNR of 25-40, revealing fine anatomical details unseen at lower resolutions for the same time. For heavier loading conditions, such as imaging of the hind legs and liver, the SNR enhancement was slightly reduced to 1.6-fold. The observed SNR was in good agreement with the expected SNR gain correlated with the loaded-quality factor of RF coils from the EM simulations. With the aid of this end-user-friendly and economically attractive cryogenic RF coil, the enhanced SNR available can be used to improve resolution or reduce the duration of individual scans in a number of biomedical applications

Minimally Invasive Iliac Screw Insertion: Clinical Case Series and Technical Note

Objective To describe the technique of minimally invasive iliac screw insertion by freehand technique and using intraoperative navigation guidance. Methods Bilateral iliac screws were inserted in total of seven patients. Five patients under- went navigation guided iliac screw placement and freehand technique was performed in 2 patients. Results Total of 7 patients underwent minimally invasive iliac screw fixation in our series. The pathology in 4 of the cases was spondylodiscitis, among them 2 cases each at L5-S1 and L4-L5, one with the destruction of L5 vertebral body and the other with the destruction of both L4 and L5 vertebral bodies. Of the remaining cases, two cases , one case of sacral insufficiency fracture and the last case was implant failure after L2-L5 oblique lumbar fusion. None of the cases required conversion to open procedure or had wound or hardware related complications till the last follow-up. All patients had an uneventful post-operative period with improvement in pain scores and were mobilized on the 1st postoperative day. One 50-year-old female patient suffering from L5-S1 tubercular spondylodiscitis died due to underlying chronic kidney disease three months post-surgery. Conclusion Minimal invasive iliac screw placement with or without navigation offers the same biomechanical stability as the open approach but without the need for extensive soft tissue exposure needed for a conventional/open procedure; thereby reducing exposure-related complications , enhancing post-operative recovery and early mobilization. Incorporating intra-operative 3D navigation provides real-time multi-planar images which help in easy planning and safe screw placement whilst reducing radiation exposure

European Working Time Directive and doctors' health: a systematic review of the available epidemiological evidence

Objective: To summarise the available scientific evidence on the health effects of exposure to working beyond the limit number of hours established by the European Working Time Directive (EWTD) on physicians. Design: A systematic literature search was conducted in PubMed and EMBASE. Study selection, quality appraisal and data extraction were carried out by independent pairs of researchers using pre-established criteria. Setting: Physicians of any medical, surgical or community specialty, working in any possible setting (hospitals, primary healthcare, etc), as well as trainees, residents, junior house officers or postgraduate interns, were included. Participants: The total number of participants was 14 338. Primary and secondary outcome measures: Health effects classified under the International Classification of Diseases (ICD-10). Results: Over 3000 citations and 110 full articles were reviewed. From these, 11 studies of high or intermediate quality carried out in North America, Europe and Japan met the inclusion criteria. Six studies included medical residents, junior doctors or house officers and the five others included medical specialists or consultants, medical, dental, and general practitioners and hospital physicians. Evidence of an association was found between percutaneous injuries and road traffic accidents with extended long working hours (LWH)/days or very LWH/weeks. The evidence was insufficient for mood disorders and general health. No studies on other health outcomes were identified. Conclusions: LWH could increase the risk of percutaneous injuries and road traffic accidents, and possibly other incidents at work through the same pathway. While associations are clear, the existing evidence does not allow for an established causal or ‘dose–response’ relationship between LWH and incidents at work, or for a threshold number of extended hours above which there is a significantly higher risk and the hours physicians could work and remain safe and healthy. Policymakers should consider safety issues when working on relaxing EWTD for doctors

Minimally Invasive Augmented Fixation for Anatomical Reduction of Grade 2 and Grade 3 Listhesis in Patients with Osteoporosis

Study Design A retrospective study. Purpose To study the efficacy of augmented fixation for anatomical reduction of grade 2 and grade 3 listhesis in patients with osteoporosis. Overview of Literature Spondylolisthesis in osteoporotic patients requiring spinal fixation are associated with complications such as loss of surgical construct stability, screw pulling out, and screw loosening. Augmented fixation is a novel strategy to achieve necessary construct integrity. Methods Thirteen consecutive patients with grade 2 or grade 3 listhesis, with proven osteoporosis on dual energy X-ray absorptiometry (DEXA) scan, and who underwent augmented fixation for reduction of listhesis were retrospectively analyzed. In all patients, surgical access was achieved with a fixed 22 mm tubular retractor. A modified technique of bilateral, sequential, transforaminal decompression and discectomy, followed by reduction of listhesis using unilaterally placed augmented screws was employed in all the cases. Patients were followed up with plain X-rays at regular intervals to assess for implant stability and fusion status. All patients were started on medical treatment for osteoporosis. Results The mean age of the patients was 52.46 years, with 12 females and one male. The median T-score on DEXA scan was −3.0. Of the 13 patients, listhesis was at L4–L5 in five and at L5–S1 in eight. Nine patients had grade 2 listhesis, while four patients had grade 3 listhesis. Complete reduction was achieved in 10 patients. The median duration of follow-up was 18 months. Postoperative outcomes were satisfactory in all cases. Conclusions Augmented fixation is a useful technique for achieving anatomical reduction of listhesis in patients with osteoporosis

Groundwater recharge sources in the Gandak alluvial aquifer, NE India : how important is leakage from irrigation canals?

Alluvial sediments in the Indo-Gangetic Basin (IGB) form one of the world’s largest and most heavily used aquifer systems. There is clear evidence for overabstraction and/or groundwater contamination in some parts of the IGB, but not in others. The hydrogeology and external influences on groundwater across the aquifer are complex and diverse. Of these influences, the role of leakage from irrigation canals is now a fundamental part of groundwater dynamics in the IGB aquifer. In some areas, aquifer recharge contains a high proportion of canal leakage (Joshi et al. 2018), but in others it is much less (Lapworth et al. 2015). The Gandak, in NE India, is a sub catchment of the IGB and provides an excellent laboratory for studying the evolution of groundwater-river-canal dynamics in the centre of the basin. Our study, carried out as part of the joint UK-India funded CHANSE project, is the first detailed investigation of the hydrochemistry, stable isotopes and residence time of groundwater in the Gandak aquifer, to quantify the contribution of recharge to the aquifer from canal leakage, the Gandak River and local monsoon rainfall; and to characterise groundwater flow and mixing behaviour

Primary cerebello-pontine angle melanoma: a case report

Intra-cranial melanomas are commonly metastatic from primary melanoma elsewhere in the body. The primary occurrence of a melanoma in the brain parenchyma is rare. We report a case of 38 year aged woman who presented with deviation of left eye and headache. On imaging, a space occupying lesion was found in the left Cerebello-pontine angle and a preoperative diagnosis of meningioma was made. She underwent left retro-mastoid sub-occipital craniectomy and excision of a black vascular tumor. Histopathological examination revealed a melanoma which was confirmed with Immunohistochemical assay. Search for dermal, mucous and ocular lesions were negative. She received adjuvant radiation to the post- operative tumor bed to 5400cGy in 30 fractions using Intensity Modulated Radiation Therapy technique along with concurrent Temozolomide. She tolerated the treatment well and is symptom free 12 months after treatment. Primary Melanomas are rare lesions of the Cerebello-pontine angle and its radiological features, evaluation and management have been discussed.-------------------Cite this article as: Ponni A, Jagannatha A, Gururajachar J, Harjani R, Koushik K, Subramanian N, Sowmya R, Varma R. Primary cerebello-pontine angle melanoma: a case report. Int J Cancer Ther Oncol 2014; 2(3):020315. DOI: 10.14319/ijcto.0203.1

Tube-assisted Minimally Invasive versus Open Posterior Decompression for Multilevel Degenerative Cervical Myelopathy: A Prospective Comparative Study

Objective There have been several reports of minimally invasive decompression for cervical canal stenosis and degenerative myelopathy. Most of these reports are for less than 4 levels and there have not been any comparative studies between Open and MIS cervical decompression for multilevel (≥4) degenerative cervical myelopathy. Methods Twenty consecutive patients were allotted to undergo either ‘Open’ cervical laminectomy (n=10) or MIS posterior cervical decompression (n=10). All patients were evaluated for 1. Clinical, (JOA, MDI, NDI, Nurick grade, Blood loss, Duration of surgery); 2. Radiological (CSA of dural sac and Spinal cord, Muscle edema on post-op T2W MRI); 3. Laboratory (TLC, CRP, ESR, CPK) and 4. Physical (Isometric neck extensor muscle strength). Differences between Open and MIS groups were calculated with respect to above parameters. Results The mean number of levels decompressed was 4.4 (range, 4–6). MIS group had significantly longer duration of surgery and lesser blood loss as compared to open group. The patients in open group were more disabled than MIS group pre-operatively, as evidenced by higher MDI and NDI. However, proportionate improvements were seen in both groups post-operatively in terms of all clinical parameters. Postoperative increase in CSA of spinal cord was also identical in both groups. Elevations in CRP and ESR were significantly higher in Open group post-operatively as compared to MIS group. Post-operative extensor neck muscle strength improved to a higher extent in MIS group as compared to open group though this was not statistically significant. No patient had any major post-operative complications. Conclusion MIS posterior cervical decompression is safe and effective, can achieve similar extent of decompression and degree of clinical improvement as compared to open surgery. MIS has definite advantages of lesser blood loss, reduced tissue injury and better improvement in post-operative neck muscle strength as compared to open surgery

Two Sides of the Same Story: Alcohol Use and HIV Risk Taking in South India

This qualitative study examines the role of alcohol in sexual risk among male migrant workers and female sex workers in two South Indian states. Most men reported using alcohol for increased energy and courage prior to their sexual experiences and to reduce feelings of loneliness and isolation. Sex workers, on the other hand, often stated that they avoided alcohol prior to sex in order to stay alert and reduce the risk of violence. Both groups reported that drinking often increased male aggression and reduced condom use. Research is needed to examine the prevalence of these patterns as well as factors associated with sexual risk and violence, in order to develop targeted interventions for these groups. Future risk reduction programs may benefit from addressing safer ways of meeting the needs expressed by the participants. This may include strategies to defuse volatile situations, safe ways of improving the sexual experience, and interventions aimed at alleviating loneliness and isolation for migrants