Urban Crisis and Humanitarian Responses: A Literature Review

Crises, such as disasters, forced migration, conflict and violence are occurring in urban areas with increasing frequency and intensity. The impacts of climate change may increase crises in future. However, humanitarian actors are finding that responding to crises in urban areas presents a new set of challenges. This includes a need for different ways of working than those previously established for humanitarian response in rural areas. This literature review, commissioned by DFID Humanitarian Policy and Partnerships Group, CHASE, looks at the current evidence-base on humanitarian response and development in urban areas, drawn from published academic literature and humanitarian agency reports. The review is structured around four main themes: complex and diverse communities; infrastructure systems; markets; and local governance structures and capacities. Its purpose is to identify key knowledge and evidence gaps and areas where further research is needed to inform more contextually appropriate and inclusive approaches to urban humanitarian response. Key knowledge and evidence gaps include the need to better understand urban systems such as urban markets, infrastructure, institutional systems and social relations in urban contexts, local recovery processes, and the experiences and perceptions of local humanitarian actors, including local governments, non-governmental organisations and affected people. Particular attention is also paid to the impacts (direct and indirect) that both crises and humanitarian interventions have on urban areas over-time. The review concludes by outlining a research agenda for supporting evidence-based humanitarian action in urban settings, including the need to: create platforms for local actors to engage in humanitarian debates, learning and research; create more robust evidence by triangulating different types of information from multiple actors and affected people; increase understanding of urban contextual issues and conditions; broaden learning of the humanitarian community to other fields, including urban development and human settlements; and expand research timeframes to encompass longitudinal studies and offer platforms for coordination for research across humanitarian agencies

Pose Recognition Based Wheelchair Propulsion from a Stationary Point for Elderly Convenience

Aging is an inevitable, natural process that reduces the functionality of the human body over time. Many tasks become too difficult to handle and the body barely hangs on. One such task is the mobility for the geriatric society. People from that age group usually find it hard to go from place to place or will have to depend on someone else for assistance. The purpose of this research is to improve the quality of life for the senior citizens. The research focuses on the design of such a robotic wheelchair which incorporates everything from hardware, software to sensor technology, computer processing and power distribution. When the senior citizen wishes to sit, they will perform a pose from a set of specified poses that elicits a response from the wheelchair in the form of forward movement making it easy for them to be seated. Before propulsion, the distance between the user and the wheelchair is calculated and recorded. While in motion, the wheelchair checks for any obstacles on its path to the user using a simple algorithm incorporating the previously calculated distance. Upon reaching the user, the wheelchair is set to alert the user by the sounding of a buzzer. In the case an obstacle is detected, the wheelchair is set to alert the user in a way that is different as compared to that of alerting the user upon successfully traversing the distance. During the experimentation phase, the wheelchair is triggered and reacts appropriately as and when the poses are performed. The Buzzer is also activated as per the case of either traversing the complete distance or encountering an obstacle. Results from the performance testing demonstrate its functionality as a possible care-giving solution to the senior citizens

Revealing the Nature of Algol Disks through Optical and UV Spectroscopy, Synthetic Spectra, and Tomography of TT Hydrae

We have developed a systematic procedure to study the disks in Algol-type binaries using spectroscopic analysis, synthetic spectra, and tomography. We analyzed 119 H-alpha spectra of TT Hya, an Algol-type eclipsing interacting binary, collected from 1985-2001. The new radial velocities enabled us to derive reliable orbital elements, including a small non-zero eccentricity, and to improve the accuracy of the absolute dimensions of the system. High resolution IUE spectra were also analyzed to study the formation of the ultraviolet lines and continuum. Synthetic spectra of the iron curtain using our new shellspec program enabled us to derive a characteristic disk temperature of 7000K. We have demonstrated that the UV emission lines seen during total primary eclipse cannot originate from the accretion disk, but most likely arise from a hotter disk-stream interaction region. The synthetic spectra of the stars, disk, and stream allowed us to derive a lower limit to the mass transfer rate of 2e-10 solar masses per year. Doppler tomography of the observed H-alpha profiles revealed a distinct accretion disk. The difference spectra produced by subtracting the synthetic spectra of the stars resulted in an image of the disk, which virtually disappeared once the composite synthetic spectra of the stars and disk were used to calculate the difference spectra. An intensity enhancement of the resulting tomogram revealed images of the gas stream and an emission arc. We successfully modeled the gas stream using shellspec and associated the emission arc with an asymmetry in the accretion disk.Comment: 46 pages, 15 figures, 6 tables, accepted by Ap

Ammonia: what adult neurologists need to know

Hyperammonaemia is often encountered in acute neurology and can be the cause of acute or chronic neurological symptoms. Patients with hyperammonaemia may present with seizures or encephalopathy, or may be entirely asymptomatic. The underlying causes are diverse but often straightforward to diagnose, although sometimes require specialist investigations. Haemodialysis or haemo(dia)filtration is the first-line treatment for acute severe hyperammonaemia (of any cause) in an adult. Here we discuss our approach to adult patients with hyperammonaemia identified by a neurologist

Mechanical stiffness and dissipation in ultrananocrystalline diamond microresonators

We have characterized mechanical properties of ultrananocrystalline diamond UNCD thin films grown using the hot filament chemical vapor deposition HFCVD technique at 680 °C, significantly lower than the conventional growth temperature of 800 °C. The films have 4.3% sp2 content in the near-surface region as revealed by near edge x-ray absorption fine structure spectroscopy. The films, 1 m thick, exhibit a net residual compressive stress of 3701 MPa averaged over the entire 150 mm wafer. UNCD microcantilever resonator structures and overhanging ledges were fabricated using lithography, dry etching, and wet release techniques. Overhanging ledges of the films released from the substrate exhibited periodic undulations due to stress relaxation. This was used to determine a biaxial modulus of 8382 GPa. Resonant excitation and ring-down measurements in the kHz frequency range of the microcantilevers were conducted under ultrahigh vacuum UHV conditions in a customized UHV atomic force microscope system to determine Young’s modulus as well as mechanical dissipation of cantilever structures at room temperature. Young’s modulus is found to be 79030 GPa. Based on these measurements, Poisson’s ratio is estimated to be 0.0570.038. The quality factors Q of these resonators ranged from 5000 to 16000. These Q values are lower than theoretically expected from the intrinsic properties of diamond. The results indicate that surface and bulk defects are the main contributors to the observed dissipation in UNCD resonators

The use of simultaneous stereo-electroencephalography and magnetoencephalography in localizing the epileptogenic focus in refractory focal epilepsy

Both magnetoencephalography and stereo-electroencephalography are used in presurgical epilepsy assessment, with contrasting advantages and limitations. It is not known whether simultaneous stereo-electroencephalography–magnetoencephalography recording confers an advantage over both individual modalities, in particular whether magnetoencephalography can provide spatial context to epileptiform activity seen on stereo-electroencephalography. Twenty-four adult and paediatric patients who underwent stereo-electroencephalography study for pre-surgical evaluation of drug-resistant focal epilepsy, were recorded using simultaneous stereo-electroencephalography–magnetoencephalography, of which 14 had abnormal interictal activity during recording. The 14 patients were divided into two groups; those with detected superficial (n = 7) and deep (n = 7) brain interictal activity. Interictal spikes were independently identified in stereo-electroencephalography and magnetoencephalography. Magnetoencephalography dipoles were derived using a distributed inverse method. There was no significant difference between stereo-electroencephalography and magnetoencephalography in detecting superficial spikes (P = 0.135) and stereo-electroencephalography was significantly better at detecting deep spikes (P = 0.002). Mean distance across patients between stereo-electroencephalography channel with highest average spike amplitude and magnetoencephalography dipole was 20.7 ± 4.4 mm. for superficial sources, and 17.8 ± 3.7 mm. for deep sources, even though for some of the latter (n = 4) no magnetoencephalography spikes were detected and magnetoencephalography dipole was fitted to a stereo-electroencephalography interictal activity triggered average. Removal of magnetoencephalography dipole was associated with 1 year seizure freedom in 6/7 patients with superficial source, and 5/6 patients with deep source. Although stereo-electroencephalography has greater sensitivity in identifying interictal activity from deeper sources, a magnetoencephalography source can be localized using stereo-electroencephalography information, thereby providing useful whole brain context to stereo-electroencephalography and potential role in epilepsy surgery planning

Temperature dependence of mechanical stiffness and dissipation in ultrananocrystalline diamond

Ultrananocrystalline diamond (UNCD) films are promising for radio frequency micro electro mechanical systems (RF-MEMS) resonators due to the extraordinary physical properties of diamond, such as high Young’s modulus, quality factor, and stable surface chemistry. UNCD films used for this study are grown on 150 mm silicon wafers using hot filament chemical vapor deposition (HFCVD) at 680°C. UNCD fixed free (cantilever) resonator structures designed for the resonant frequencies in the kHz range have been fabricated using conventional microfabrication techniques and are wet released. Resonant excitation and ring down measurements in the temperature range of 138 K to 300 K were conducted under ultra high vacuum (UHV) conditions in a custom built UHV AFM stage to determine the temperature dependence of Young’s Modulus and dissipation (quality factor) in these UNCD cantilever structures. We measured a temperature coefficient of frequency (TCF) of 121 and 133 ppm/K for the cantilevers of 350 ìm and 400 ìm length respectively. Young’s modulus of the cantilevers increased by about 3.1% as the temperature was reduced from 300 K to 138 K. This is the first such measurement for UNCD and suggests that the nanostructure plays a significant role in modifying the thermo-mechanical response of the material. The quality factor of these resonators showed a moderate increase as the cantilevers were cooled from 300 K to 138 K. The results suggest that surface and bulk defects significantly contribute to the observed dissipation in UNCD resonators

Curricular changes and interim posts during Covid-19 : graduates' perspectives

Background During the COVID-19 pandemic UK medical schools facilitated the early graduation of their final-year medical students to ‘Foundation interim Year 1 (FiY1) doctors’ through amendments made to curricula and final assessment. Such changes gave opportunity for evaluation. This study therefore aimed to explore 1) graduate perspective on the implementation of FiY1 and 2) how changes to course structures have affected self-reported preparedness for work. Methods Questionnaire surveys using Likert scale and free-text responses (n = 45), and semi-structured interviews (n = 7) were conducted with FiY1s from two UK medical schools contrasting in the amendments made to course structures. Data were analysed using quantitative methods and thematic analysis; 44% (n = 20) of respondents believed that governing health bodies had not communicated sufficiently prior to starting work. Results Graduates who had sat modified practical and written examinations reported ‘legitimacy’ and feeling more prepared compared to having not sat examinations (practical 100%, n = 17; written 88.3%, n = 15). Graduates from both schools agreed that carrying out assistantships as originally scheduled would have made them feel more prepared (91.1%, n = 41). Conclusions The implementation of FiY1 was largely well received by graduates yet assistantship programmes may fulfil a similar role in normal times. Medical schools and governing bodies must ensure effective communication channels exist with students in order to better prepare them for their first posts, especially in times of crisis. Additionally, final examinations contribute to feelings of preparedness for work and instil a sense of legitimacy, a finding which is relevant to working within the current programmatic assessment structure