Charge multiplication in severely irradiated silicon detectors is now a well proven effect that enhances their charge collection and makes them operable up to the doses anticipated for future ...super-colliders (like the high luminosity LHC at CERN). The effect is well documented but not completely understood. The multiplication is caused by impact ionisation due to hot electrons moving in the high electric field that develops near the junction in the irradiated sensors. The details of the electric field profile in the silicon bulk are not available due to the unknown spatial distribution of the inhomogeneous effective space charge in the hadron irradiated silicon bulk. The gradient of the effective space charge distribution is crucial for the formation of high electric field regions where the multiplication takes place. The electric field might be influenced by the implant forming the n–p junction and by a non-homogenous bulk space charge near the junction. Deep n+ structures (junction) could enhance or reduce the multiplication effect. Also an altered doping gradient (obtainable for example by a graded p-doping between the junction and the p-bulk) could achieve the same results. In order to achieve enhanced charge multiplication in microstrip detectors the junction has been shaped by mean of deep p-doping diffusion and of trenches etched in the silicon bulk and filled with n+ doped polysilicon to create a deep junction. We report here the result obtained with these methods before and after various doses of neutron irradiation.
Background and Aims
The impacts of the COVID‐19 pandemic have not been equal, with a disproportionate impact among ethnic minority communities. Structural inequalities in social determinants of ...health such as housing and employment have contributed to COVID‐19's impact on deprived communities, including many ethnic minority communities. To compare (1) how the UK government's “social distancing” restrictions and guidance were perceived and implemented by ethnic minority populations compared to white populations, (2) the impact of restrictions and guidance upon these groups.
Methods
An explanatory sequential mixed methods study incorporated a quantitative survey and qualitative semi‐structured interviews to explore individual perceptions and experiences of COVID‐19 and the national restrictions. Survey participants (n = 1587) were recruited from North West England; 60 (4%) participants were from ethnic minority communities. Forty‐nine interviews were conducted; 19 (39%) participants were from ethnic minority communities. Interviews were transcribed verbatim and analysed using a thematic approach. Data collection was between April and August 2020.
Results
Significant differences in demographics and household overcrowding were observed between white vs ethnic minority survey respondents, who were also significantly less confident in their knowledge of COVID‐19, less likely to be high‐risk drinkers, and marginally more likely to have experienced job loss and/or reduced household income. There were no group differences in wellbeing, perceptions, or nonfinancial impacts. Two inter‐related themes included: (1) government guidance, incorporating people's knowledge and understanding of the guidance and their confusion/frustration over messaging; (2) the impacts of restrictions on keyworkers, home‐schooling, working from home and changes in lifestyle/wellbeing.
Conclusions
Further research is needed on the long‐term impacts of COVID‐19 on ethnic minority communities. If policy responses to COVID‐19 are to benefit ethnic minority communities, there is a need for future studies to consider fundamental societal issues, such as the role of housing and economic disadvantage.
Highlights
What is known about this topic?
The COVID‐19 pandemic has impacted the entire world, however it has had disproportionate impacts on ethnic minority communities.
‘Social distancing’ is a public health intervention that has been utilised in previous pandemics where measures are put in place to encourage individuals to undertake a number of changes to their social behaviours to increase physical distance from others and to reduce number of contacts with other people.
Living conditions such as overcrowding are a risk factor for ill health, including from COVID‐19.
What this paper add?
Ethnic minority respondents were significantly more concerned about the educational impacts on their children.
Living in overcrowded homes significantly affected the ethnic minority respondents with regard to increased risk within their home environment, less space for privacy for working from home and education/welfare needs of children.
More practical and relevant government guidance is needed for ethnic minority communities and future policy should consider the economic and societal impacts for ethnic minority workers.
A radiation hard n+-in-p micro-strip sensor for the use in the Upgrade of the strip tracker of the ATLAS experiment at the High Luminosity Large Hadron Collider (HL-LHC) has been developed by the ...“ATLAS ITk Strip Sensor collaboration” and produced by Hamamatsu Photonics.
Surface properties of different types of end-cap and barrel miniature sensors of the latest sensor design ATLAS12 have been studied before and after irradiation. The tested barrel sensors vary in “punch-through protection” (PTP) structure, and the end-cap sensors, whose stereo-strips differ in fan geometry, in strip pitch and in edge strip ganging options. Sensors have been irradiated with proton fluences of up to 1×1016 neq/cm2, by reactor neutron fluence of 1×1015 neq/cm2 and by gamma rays from 60Co up to dose of 1MGy. The main goal of the present study is to characterize the leakage current for micro-discharge breakdown voltage estimation, the inter-strip resistance and capacitance, the bias resistance and the effectiveness of PTP structures as a function of bias voltage and fluence. It has been verified that the ATLAS12 sensors have high breakdown voltage well above the operational voltage which implies that different geometries of sensors do not influence their stability. The inter-strip isolation is a strong function of irradiation fluence, however the sensor performance is acceptable in the expected range for HL-LHC. New gated PTP structure exhibits low PTP onset voltage and sharp cut-off of effective resistance even at the highest tested radiation fluence. The inter-strip capacitance complies with the technical specification required before irradiation and no radiation-induced degradation was observed. A summary of ATLAS12 sensors tests is presented including a comparison of results from different irradiation sites. The measured characteristics are compared with the previous prototype of the sensor design, ATLAS07.
•Surface study verified high radiation resistance of developed n-in-p strip sensors.•Sensors have high breakdown voltage before and after irradiation.•Inter-strip capacitance is sufficiently low and does not change with irradiation.•Primary factor of inter-strip resistance decrease is total ionizing dose.•New gated PTP doubles current flowing into bias rail without onset voltage increase.
Objective To determine the specificity and sensitivity of a commercial copro‐antigen ELISA for the detection of F asciola hepatica infection in cattle and sheep and to assess the suitability of the ...test for use in horses. Methods Testing was done on more than 100 negative faecal samples from each of sheep, cattle and horses and on at least 40 positive faecal samples from each species. Positive samples were selected based on a positive sedimentation test for liver fluke eggs. Faecal samples of animals from W estern A ustralia, which is free of liver fluke infection, served as negative controls. Specificity and sensitivity were assessed for each species using the recommended kit cut‐off and also custom cut‐offs specific for each species based on the mean plus 3‐fold standard deviation of the mean of the negative samples for each species. Results Using the cut‐off recommended by the kit manufacturer, the specificity was 100% for all species and the sensitivity was 88%, 80% and 9% for sheep, cattle and horses, respectively. Using the lower custom cut‐offs for each species improved the sensitivity to 100% for sheep, 87% for cattle and 28% for horses, while maintaining the specificity above 99% for all species. Conclusions The sensitivity of the commercial copro‐antigen ELISA can be improved by using custom cut‐off values for each species. With this modification, it is a suitable alternative screening test to the currently used sedimentation test for border control of sheep and cattle movement. The test is not suitable for use in horses.
The high-luminosity LHC will present significant challenges for tracking systems. ATLAS is preparing to upgrade the entire tracking system, which will include a significantly larger pixel detector. ...This paper reports on the development of large area planar detectors for the outer pixel layers and the pixel endcaps. Large area sensors have been fabricated and mounted onto 4 FE-I4 readout ASICs, the so-called quad-modules, and their performance evaluated in the laboratory and testbeam. Results from characterisation of sensors prior to assembly, experience with module assembly, including bump-bonding and results from laboratory and testbeam studies are presented.
Pixel detectors will be extensively used for the four innermost layers of the upgraded ATLAS experiment at the future High Luminosity LHC (HL-LHC) at CERN. The total area of pixel sensors will be ...over 5m2. The silicon sensors that will instrument the pixel volume will have to face several technology challenges. They will have to withstand doses up to 2×1016neqcm−2, to have a reduced inactive area at the edge of the sensors still being able to hold 1000V bias voltage and to be relatively low cost considering the large area to be covered. N-side readout on p-type bulk is the most promising technology for satisfying the various requirements. Several sensor types have been produced in the UK, conceived for various readout systems, for studying the properties of n-in-p and n-in-n sensors before and after irradiation with test beam and laboratory measurements. The status of these studies is presented here.
To compare the characteristics, presentation, and surgical outcome of patients with microdiscectomies at L1-L2 and L2-L3 with those we treated at L3-L4. We further sought to compare these results ...with those reported in the literature for discectomies at the L4-L5 and L5-S1 levels.
We reviewed the clinical data collected from 69 patients who had 72 L1-L2, L2-L3, and L3-L4 microdiscectomies performed from 1989 to 1999 at the New York University Medical Center. Patients who had surgery at L1-L2 or L2-L3 were grouped and compared with those treated at the L3-L4 level. Patients' charts were retrospectively reviewed at a mean of 12.9 months after surgery for presenting signs and symptoms, patient characteristics, and surgical outcome. Long-term follow-up via telephone interview was obtained at an average of 81.3 months after surgery.
In the L1-L2 + L2-L3 group, 58% of the patients had previous lumbar disc surgery, compared with only 10% of those in the L3-L4 group, and 20% in the L1-L2 + L2-L3 group required a fusion during the procedure compared with only 10% in the L3-L4 group. These differences are both statistically significant. The short-term chart review demonstrates that only 58% and 53% of patients in the L1-L2 + L2-L3 group were improved with regard to radicular and back pain, respectively, whereas those in the L3-L4 group reported 94 and 87% rates of improvement in the same categories, both highly statistically significant findings. The long-term follow-up confirmed a highly statistically significantly worse outcome in the L1-L2 + L2-L3 group, with only 33% of patients reporting an improvement in their economic or functional status, compared with an 88% rate of improvement in the L3-L4 group. The outcome of our patients with L3-L4 herniations was similar to that reported in the literature for herniations at L4-L5 and L5-S1.
Herniated discs at the L1-L2 or L2-L3 level are different entities from those at lower levels of the lumbar spine. The surgical outcome in terms of postoperative back and radicular pain is worse for herniated discs at L1-L2 and L2-L3 compared with those treated at L3-L4. Our patients with L1-L2 or L2-L3 surgically treated herniated discs were more likely to have had previous lumbar surgery and required a fusion more often than their counterparts with L3-L4 herniated discs.
The question of how our perceived reality is constructed and subsequently how our mind has evolved such that we are able to both perceive and subsequently alter our own causality or even our own ...evolution within this reality has been a long running open question. Referred to as "The Hard Problem". There have been many theoretical interpretations on the nature of causal self-observance - hereafter referred to as 'consciousness'. The current paper introduces the reader to the indeterminable operator - "The Third State". The Third State is a term used to describe space itself in relation to the position of all things. As the paper shall show, The Third State is a required omnipresent and universal operator in the otherwise binary realm of data arrow right information. The Third State augments the accepted binary operators to produce the required 'tristate' condition that facilitates the required probabilistic nature of the conscious manifestation. Secondly the Unity Magnitude Um scale, which facilitates the bounding of quantum probabilistic memory in a finite model. The paper further introduces the reader to a model and experimental theory that suggests all things we perceive as physical reality can be fabricated from primitive components of data, bits - matter / antimatter / something or nothing. That facilitated by the Third State, our immediate present reality as we experience it and theretofore consciousness is a simultaneous product of the current physical configuration of the frequency stable systems of which we are comprised , interpreted past reality, self-predicted future provided by cyclic frequency stable systems and the immediate physical and sensory state including recursive imagination systems generated by the output of these perturbed frequency stable systems in the cyclic feedback process - ultimately perturbed by, but as one unified with the stochastic processes in relation to the quantum cosmological domain.
The ATLAS pixel detector for the HL-LHC requires the development of large area pixel modules that can withstand doses up to 1016 1MeVneqcm−2. The area of the pixel detector system will be over 5m2 ...and as such low cost, large area modules are required. The development of a quad module based on 4 FE-I4 readout integrated chips (ROIC) will be discussed. The FE-I4 ROIC is a large area chip and the yield of the flip-chip process to form an assembly is discussed for single chip assemblies. The readout of the quad module for laboratory tests will be reported.
The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe.
Patient demographics, ...findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance (MR) images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyrus. The tumors were located in the dominant hemisphere in 18 patients (64%); had a mean diameter of 39 mm (range 14-69 mm); were isolated to the superior parietal lobule in six patients (21%) and to the inferior parietal lobule in eight patients (29%); and involved both lobules in 14 patients (50%). Gross-total resection, documented by MR imaging, was achieved in 24 patients (86%). Postoperatively, nine patients (32%) experienced new neurological deficits, whereas seven (25%) had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level (association) parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved.
Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits (for example, a visual field loss or cortical sensory syndrome) occurred in patients regardless of hemispheric dominance.
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