High Dependency Unit Admissions among Patients with Lower Extremity Long Bone Fracture Visiting the Department of Orthopaedics in a Tertiary Care Centre.

Introduction: Lower extremity long bone, femoral and tibial shaft, fractures often have associated injuries. Patients with lower extremity long bone fractures in the Department of Orthopaedics can land up in high dependency unit admissions, mostly due to underlying complications. The study aimed to find out the prevalence of high dependency unit admissions among patients with lower extremity long bone fractures visiting the Department of Orthopaedics in a tertiary care centre. Methods: A descriptive cross-sectional study was conducted among patients with lower extremity long bone fractures in a tertiary care centre. The data from 1 March 2017 to 31 January 2020 was collected from the medical records from 1 August 2020 to 30 September 2020. All patients with femoral or tibial shaft fractures in isolation or a part of a multi-system injury were included. Patients with inadequate data were excluded. A convenience sampling method was used. The point estimate was calculated at a 95% Confidence Interval. Results: Among 507 patients with lower extremity long bone fractures, 137 (27.55%) (23.66-31.44, 95% Confidence Interval) required high dependency unit admission. Among them, 119 (86.86%) were males. A total of 71 (51.82%) cases involved 2-wheelers. Conclusions: The prevalence of high dependency unit admission among patients with lower extremity long bone fractures was high and majority of them required multidisciplinary approach. Keywords: femoral fractures; prevalence; tibial fractures; traffic accidents.

Experimental and numerical study of Conoscopic Interferometry sensitivity for optimal acoustic pulse detection in ultrafast acoustics.

Conoscopic interferometry is a promising detection technique for ultrafast acoustics. By focusing a probe beam through a birefringent crystal before passing it through a polarizer, conoscopic interferences sculpt the spatial profile of the beam. The use of these patterns for acoustic wave detection revealed a higher detection sensitivity over existing techniques, such as reflectometry and beam distortion detection. However, the physical origin of the increased sensitivity is unknown. In this work, we present a model, describing the sensitivity behavior of conoscopic interferometry with respect to the quarter-wave plate orientation and the diaphragm aperture, which is validated experimentally. Using the model, we optimize the detection sensitivity of conoscopic interferometry. We obtain a maximal sensitivity of detection when placing the diaphragm edge on the dark fringes of the conoscopic interference patterns. In the configurations studied in this work, conoscopic interferometry can be 18 dB more sensitive to acoustic waves than beam distortion detection.

Mapping the venture capital and private equity research: a bibliometric review and future research agenda.

The fields of venture capital and private equity are rooted in financing research on capital budgeting and initial public offering (IPO). Both fields have grown considerably in recent times with a heterogenous set of themes being explored. This review presents an analysis of research in both fields. Using a large corpus from the Web of Science, this study used bibliometric analysis to present a comprehensive encapsulation of the fields' geographical focus, methodological choices, prominent themes, and future research directions. Noteworthily, the foundational themes in venture capital research are venture capital adoption and financing processes, venture capital roles in business, venture capital governance, venture capital syndication, and venture capital and creation of public organizations. In private equity research, style drift into venture capital emerges as a key theme alongside buyouts and privatization, and valuation and performance of private equity investment.

Financing is an important aspect of business that creates opportunities for investors and invested entities. Venture capital and private equity are two major vehicles of financing a business. While venture capital manifests as small investments that support the business operations of a large number of promising firms (more risky) in the early stage (startup), private equity transpires as large investments that support the business expansion of a small number of stable firms (less risky) in the later stage (scaleup). This study presents state-of-the-art insights into the current trends and future directions of venture capital and private equity using a bibliometric analysis of high-quality research on these forms of financing.

Aberration calibration and correction with nano-scatterers in digital holographic microscopy for semiconductor metrology.

Overlay metrology measures pattern placement between two layers in a semiconductor chip. The continuous shrinking of device dimensions drives the need to explore novel optical overlay metrology concepts that can address many of the existing metrology challenges. We present a compact dark-field digital holographic microscope that uses only a single imaging lens. Our microscope offers several features that are beneficial for overlay metrology, like a large wavelength range. However, imaging with a single lens results in highly aberrated images. In this work, we present an aberration calibration and correction method using nano-sized point scatterers on a silicon substrate. Computational imaging techniques are used to recover the full wavefront error, and we use this to correct for the lens aberrations. We present measured data to verify the calibration method and we discuss potential calibration error sources that must be considered. A comparison with a ZEMAX calculation is also presented to evaluate the performance of the presented method.

Research Published in Management International Review from 2006 to 2020: A Bibliometric Analysis and Future Directions.

The Management International Review (MIR) celebrated its 60th anniversary in 2020. In commemoration of this event, we use a bibliometric analysis to present a retrospective on the journal by analyzing its content for the years between 2006 and 2020. We find that the collaboration culture in MIR has risen over time with the increase in the median size of author teams. Moreover, the collaboration network has become more global over time. The methodology used in the journal is predominantly empirical and quantitative with archival data sources most commonly used. The bibliographic coupling of the MIR corpus reveals that the major themes in the journal revolve around "culture," "emerging economies," "innovation, knowledge transfer, and absorptive capacity," "internationalization process," "culture and entry modes," and "internationalization and performance." A comparison with other leading international business journals provides distinct pathways in which MIR may continue to grow. Finally, it is important to note that while the share of conceptual studies has decreased significantly in the last 15 years, the MIR editors want to see more novel and theoretically grounded conceptual articles in the journal.

Diffraction-based overlay metrology using angular-multiplexed acquisition of dark-field digital holograms.

In semiconductor device manufacturing, optical overlay metrology measures pattern placement between two layers in a chip with sub-nm precision. Continuous improvements in overlay metrology are needed to keep up with shrinking device dimensions in modern chips. We present first overlay metrology results using a novel off-axis dark-field digital holographic microscopy concept that acquires multiple holograms in parallel by angular multiplexing. We show that this concept reduces the impact of source intensity fluctuations on the noise in the measured overlay. With our setup we achieved an overlay reproducibility of 0.13 nm and measurements on overlay targets with known programmed overlay values showed good linearity of R2= 0.9993. Our data show potential for significant improvement and that digital holographic microscopy is a promising technique for future overlay metrology tools.

DNA viruses and cancer: insights from evolutionary biology.

When it comes to understanding the exact mechanisms behind the virus induced cancers, we have often turned to molecular biology. It would be fair to argue that our understanding of cancers caused by viruses has significantly improved since the isolation of Epstein-Barr virus from Burkitt's lymphoma. However they are some important questions that remain unexplored like what advantage do viruses derive by inducing carcinogenesis? Why do viruses code for the so called oncogenes? Why DNA viruses are disproportionately linked to cancers? These questions have been addressed from the lens of evolutionary biology in this review. The evolutionary analysis of virus induced cancer suggests that persistent strategy of infection could be a stable strategy for DNA viruses and also the main culprit behind their tendency to cause cancer. The framework presented in the review not only explains wider observations about cancer caused by viruses but also offers fresh predictions to test the hypothesis.

A safe percutaneous technique for the reduction of irreducible femoral neck fractures using ultrasound localization of the femoral vascular and nervous structures at the hip.

We present a safe percutaneous technique for the placement of Kirschner wires into the femoral head to assist in the reduction of irreducible femoral neck fractures using ultrasound to identify the vascular and nervous structures about the hip.From January 2011 to June 2014, a total of 36 patients (25 males and 11 females) were enrolled in this study. Patients were placed on a fracture reduction table for limb traction. After 3 unsuccessful reductions with limb traction, ultrasound-guided localization of the patient's femoral artery, vein, and nerve at the hip was performed. These structures were marked on the overlying skin and then Kirschner wires were inserted into the femoral head avoiding these marked structures. After the surgery, the Kirschner wire insertions were routinely reviewed by ultrasound, the hip fracture reduction and the femoral nerve sensorimotor function were routinely examined as well.All 36 patients with an irreducible variant of a femoral neck fracture showed anatomic reduction under C-arm fluoroscopy using ultrasound to avoid K wire injury to the femoral vascular structures and nerve. No major vascular injury during operation. In post-surgical ultrasound examination, local hematoma formation was not evident. There was normal function of the femoral nerve. On follow-up, there were no infections, wound problems, recurrence of fracture displacement, laxity, or implant breakage.Preoperative ultrasonic localization of the femoral artery, vein, and femoral nerve safely allowed. Kirschner wire placement under C-arm fluoroscopy into the femoral head to assist in fracture reduction. This assisted reduction method for irreducible femoral neck fractures had a number of advantages, including closed anatomic reduction with minimal attempts, used simple equipment, and avoided further destruction of the blood supply to the femoral head.

Extended viewing angle holographic display system with tilted SLMs in a circular configuration.

This paper presents an extended viewing angle holographic display for reconstruction of real world objects in which the capture and display systems are decoupled. This is achieved by employing multiple tilted spatial light modulators (SLMs) arranged in a circular configuration. In order to prove the proper reconstruction and visual perception of holographic images the Wigner distribution function is employed. We describe both the capture system using a single static camera with a rotating object and a holographic display utilizing six tilted SLMs. The experimental results based on the reconstruction of computer generated and real world scenes are presented. The coherent noise removal procedure is described and implemented. The experiments prove the possibility to view images reconstructed in the display binocularly and with good quality.

Quantization noise and its reduction in lensless Fourier digital holography.

Digital holography is an imaging technique that enables recovery of topographic 3D information about an object under investigation. In digital holography, an interference pattern is recorded on a digital camera. Therefore, quantization of the recorded hologram is an integral part of the imaging process. We study the influence of quantization error in the recorded holograms on the fidelity of both the intensity and phase of the reconstructed image. We limit our analysis to the case of lensless Fourier off-axis digital holograms. We derive a theoretical model to predict the effect of quantization noise and we validate this model using experimental results. Based on this, we also show how the resultant noise in the reconstructed image, as well as the speckle that is inherent in digital holography, can be conveniently suppressed by standard speckle reduction techniques. We show that high-quality images can be obtained from binary holograms when speckle reduction is performed.

Fixed-point numercial-reconstruction for digital holographic microscopy.

In this Letter, we study the reconstruction of digital holograms of microscopic objects using a fixed-point representation of the numercial-reconstruction process. For different bit levels in our fixed-point reconstruction algorithm, we investigate the errors introduced to both the reconstructed image intensity and the unwrapped quantitative phase information. Experimental results based on a microscopic lens array are provided.

Twin removal in digital holography using diffuse illumination.

A method to numerically remove the twin image for inline digital holography, using multiple digital holograms, is discussed. Each individual hologram is recorded by using a statistically independent speckle field to illuminate the object. If the holograms are recorded in this manner and then numerically reconstructed, the twin image appears as a different speckle pattern in each of the reconstructions. By performing speckle-reduction techniques the presence of the twin image can be greatly reduced. A theoretical model is developed, and experimental results are presented that validate this approach. We show experimentally that the dc object intensity term can also be removed by using this technique.

Holographic recording in acrylamide photopolymers: thickness limitations.

Holographic recording in thick photopolymer layers is important for application in holographic data storage, volume holographic filters, and correlators. Here, we studied the characteristics of acrylamide-based photopolymer layers ranging in thickness from 250 microm to 1 mm. For each thickness, samples with three different values of absorbance were studied. By measuring the diffraction efficiency growth of holographically recorded gratings and studying the diffraction patterns obtained, the influence of scattering on the diffraction efficiency of thick volume holographic gratings was analyzed. It was found that, above a particular thickness and absorbance, the diffraction efficiency significantly decreased because of increased holographic scattering. From the diffraction efficiency dependence on absorbance and thickness it is possible to choose photopolymer layer properties that are suitable for a particular holographic application. This study was carried out to determine the highest layer thickness that could be used for phase code multiplexed holographic data storage utilizing thick photopolymer layers as a recording medium. Based on our studies to date we believe that the layer to be used for phase coded reference beam recording with 0.1 absorbance at 532 nm can have a thickness up to 450 microm. The potential use of thicker layers characterized by low scattering losses is part of our continuing research.

Technique for characterization of dimensional changes in slanted holographic gratings by monitoring the angular selectivity profile.

A method has been developed for retrieving the complete angular selectivity profile of transmission holographic gratings in one step. The method is applied to study in real time the shrinkage and changes in the effective optical thickness of a slanted holographic grating recorded in an acrylamide-based photopolymer. It can form the basis of a holographic sensor of analytes that cause a thickness change in the holographic medium. It can also be useful for the study and optimization of holographic recording materials and for quality control during production of holographic optical elements.