23 research outputs found

    The effect of doping methods on electrical properties and micromorphology of polysilicon gate electrode in submicron CMOS devices

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    Two doping methods for introducing phosphorus atoms into polysilicon to form a gate electrode for 0.5 mm CMOS were investigated. These methods were ion implantation and the ”in-situ” one (it is also known as thermal diffusion). For the in-situ method, the concentration of 1.8.10²⁰cm-³ for Si₂H₆ and phosphane (PH3) were used, in the course of ion implantation applying two different doses: 2.0.10¹⁶ and 3.10¹⁶cm-² at 40 keV. The micromorphology of the polysilicon surface was studied using the atomic force microscopy (AFM). The polysilicon thickness obtained via the in-situ method ranged between 12.35 and 26.08 nm, with an average value thickness of 18.0 nm, and its sheet resistance value was 21±1 ohm/square. As for the ion implantation method, at the lower doses the thickness ranged at about 12.00 upto 46.0 nm with an average value of 24.0 nm, and its sheet resistance values were of 36±13 and 45±21 ohm/square, respectively. At the higher doses, the thickness varied from 12.16 to 47.84 nm with an average meaning 23.96 nm, and its sheet resistance value was between 25 to 40 ohm/square. Therefore, polysilicon doped by the in-situ method has smoother and thinner surface and possesses better electrical properties

    Pots, plants and animals:broad-spectrum subsistence strategies in the Early Neolithic of the Moroccan Rif region

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    The transition from hunter-gathering to food-producing societies in the Mediterranean zone of north Africa was complex and variable, likely influenced by local ecological conditions as well as the socio-economic origins of the population. The adoption of domestic plants and animals was piecemeal, with hunting and gathering continuing as an important part of local subsistence strategies. Here, we investigate the timing and extent of the adoption of agricultural practices, namely herding and cultivation, in three diverse coastal and inland Early Neolithic sites in the Mediterranean Maghreb region, namely Ifri Oudadane, Ifri n’Etsedda and Hassi Ouenzga. Results from absorbed lipid residues extracted from 306 potsherds from these sites are correlated with information from faunal and archaeobotanical assemblages. Our findings suggest that agricultural practices, regarded as being of Neolithic origin, were never fully adopted in the Maghreb but rather that these farmer/foragers adopted a range of strategies including low-level food production (exploiting cereals and animal products, including meat and milk), gathering of wild plants and marine shellfish, and hunting both small and large sized game. These broad-spectrum farmer/foragers were clearly both flexible and resourceful and likely adapted their subsistence practices to maximise resource availability in an increasingly unpredictable environment

    The Mesolithic-Neolithic transition in southern Iberia

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    New data and a review of historiographic information from Neolithic sites of the Malaga and Algarve coasts (southern Iberian Peninsula) and from the Maghreb (North Africa) reveal the existence of a Neolithic settlement at least from 7.5 cal ka BP. The agricultural and pastoralist food producing economy of that population rapidly replaced the coastal economies of the Mesolithic populations. The timing of this population and economic turnover coincided with major changes in the continental and marine ecosystems, including upwelling intensity, sea-level changes and increased aridity in the Sahara and along the Iberian coast. These changes likely impacted the subsistence strategies of the Mesolithic populations along the Iberian seascapes and resulted in abandonments manifested as sedimentary hiatuses in some areas during the Mesolithic-Neolithic transition. The rapid expansion and area of dispersal of the early Neolithic traits suggest the use of marine technology. Different evidences for a Maghrebian origin for the first colonists have been summarized. The recognition of an early North-African Neolithic influence in Southern Iberia and the Maghreb is vital for understanding the appearance and development of the Neolithic in Western Europe. Our review suggests links between climate change, resource allocation, and population turnover. (C) 2011 University of Washington. Published by Elsevier Inc. All rights reserved.Fundacao para a Ciencia e a Tecnologia (Portugal); European Science Foundation [PTDC/HAH/64548/2006]; European Union; Fundacao para a Ciencia e Tecnologia; Ministerio de Ciencia e Innovacion, Spain [HAR 2008-1920, CGL2009-07603, CTM2009-07715, CSD2006-00041, HAR2008-06477-C03-03/HIST]; European Research Council [2008-AdG 230561]; MARM [200800050084447]; Project RNM [05212]; Junta de Andalucia, Spain [0179]; FCT [SFRH/BPD/26525/2006]; CSIC "JAE-Doc"info:eu-repo/semantics/publishedVersio

    Experience of the Coronavirus (COVID-19) patient care in the Amsterdam region: Optimization of acute care organization

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    The Coronavirus (COVID-19) pandemic causes a large number of patients to simultaneously be in need of specialized care. In the Netherlands, hospitals scaled up their ICU and clinical admission capacity at an early stage of the pandemic. The importance of coordinating resources during a pandemic has already been emphasized in the literature. Therefore, in order to prevent hospitals from being overwhelmed by COVID-19 admissions, national and regional task forces were established for the purpose of coordinating patient transfers. This review describes the experience of ROAZ region Noord-Holland Flevoland, in coordinating patient transfers in the Amsterdam region. In total, 130 patient transfers were coordinated by our region, of which 73% patients were transferred to a hospital within the region. Over a two-month period, similarities regarding days with increased patient transfers were seen between our region and the national task force. In parallel, an increased incidence in hospital admissions in the Netherlands was observed. During a pandemic, an early upscale (an increase in surge spaces) of hospital admission capacity is imperative. Furthermore, it is preferred to establish national and regional task forces, coordinated by physicians experienced and trained in handling crisis situations, adhering full transparency regarding hospital admission capacity

    In-House Attending Trauma Surgeon Does Not Reduce Mortality in Patients Presented to a Level 1 Trauma Center

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    Abstract Background: Trauma is the leading cause of death in the Western world. Trauma systems have been paramount in opposing this problem. Commonly, Level 1 Trauma Centers are staffed by in-house (IH) attending trauma surgeons available 24/7, whereas other institutions function on an on-call (OC) basis with defined response times. There is on-going debate about the value of an IH attending trauma surgeon compared to OC trauma surgeons regarding clinical outcome. Methods: This study was performed at a tertiary care facility complying with all requirements to be a designated Level 1 Trauma Center as defined by the American College of Surgeons Committee on Trauma (ACSCOT). Inclusion occurred from January 1, 2012 through December 31, 2013. Patients were assigned an identifier for IH trauma surgeon attendance versus OC attendance. The primary outcome variable studied was overall mortality in relation to IH or OC attending trauma surgeons. Additionally, time to operating theater, hospital length-of-stay (HLOS), and intensive care unit (ICU) admittance were investigated. Results: A total of 1,287 unique trauma cases in 1,285 patients were presented to the trauma team. Of all cases, 712 (55.3%) occurred between 1700h and 0800h. These 712 cases were treated by an IH attending in 66.3% (n = 472) and an OC attending in 33.7% (n = 240). In the group of patients treated by an IH attending trauma surgeon, the overall mortality rate was 5.5% (n = 26); in the group treated by an OC attending, the overall mortality rate was 4.6% (n = 11; P = .599). Cause of death was traumatic brain injury (TBI) in 57.6%. No significant difference was found in the time between initial presentation at the trauma room and arrival in the operating theater. Conclusion: In terms of trauma-related mortality during non-office hours, no benefit was demonstrated through IH trauma surgeons compared to OC trauma surgeons

    In-House Attending Trauma Surgeon Does Not Reduce Mortality in Patients Presented to a Level 1 Trauma Center

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    Abstract Background: Trauma is the leading cause of death in the Western world. Trauma systems have been paramount in opposing this problem. Commonly, Level 1 Trauma Centers are staffed by in-house (IH) attending trauma surgeons available 24/7, whereas other institutions function on an on-call (OC) basis with defined response times. There is on-going debate about the value of an IH attending trauma surgeon compared to OC trauma surgeons regarding clinical outcome. Methods: This study was performed at a tertiary care facility complying with all requirements to be a designated Level 1 Trauma Center as defined by the American College of Surgeons Committee on Trauma (ACSCOT). Inclusion occurred from January 1, 2012 through December 31, 2013. Patients were assigned an identifier for IH trauma surgeon attendance versus OC attendance. The primary outcome variable studied was overall mortality in relation to IH or OC attending trauma surgeons. Additionally, time to operating theater, hospital length-of-stay (HLOS), and intensive care unit (ICU) admittance were investigated. Results: A total of 1,287 unique trauma cases in 1,285 patients were presented to the trauma team. Of all cases, 712 (55.3%) occurred between 1700h and 0800h. These 712 cases were treated by an IH attending in 66.3% (n = 472) and an OC attending in 33.7% (n = 240). In the group of patients treated by an IH attending trauma surgeon, the overall mortality rate was 5.5% (n = 26); in the group treated by an OC attending, the overall mortality rate was 4.6% (n = 11; P = .599). Cause of death was traumatic brain injury (TBI) in 57.6%. No significant difference was found in the time between initial presentation at the trauma room and arrival in the operating theater. Conclusion: In terms of trauma-related mortality during non-office hours, no benefit was demonstrated through IH trauma surgeons compared to OC trauma surgeons

    Operational experience of the Dutch helicopter emergency medical services (HEMS) during the initial phase of the COVID-19 pandemic: jeopardy on the prehospital care system?

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    Purpose: The SARS-CoV-2 virus has disrupted global and local medical supply chains. To combat the spread of the virus and prevent an uncontrolled outbreak with limited resources, national lockdown protocols have taken effect in the Netherlands since March 13th, 2020. The aim of this study was to describe the incidence, type and characteristics of HEMS and HEMS-ambulance ‘Lifeliner 1’ dispatches during the initial phase of the COVID-19 pandemic compared to the same period one year prior. Methods: A retrospective review of all HEMS and HEMS-ambulance ‘Lifeliner 1’ dispatches was performed from the start of Dutch nationwide lockdown orders from March 13th until May 13th, 2020 and the corresponding period one year prior. Dispatch-, operational-, patient-, injury-, and on-site treatment characteristics were extracted for analysis. In addition, the rate of COVID-19 positively tested HEMS personnel and the time physicians were unable to take call was described. Results: During the initial phase of the COVID-19 pandemic, the HEMS and HEMS-ambulance was requested in 528 cases. One year prior, a total of 620 requests were received. The HEMS (helicopter and ambulance) was cancelled after deployment in 56.4% of the COVID-19 cohort and 50.7% of the historical cohort (P = 0.05). Incident location type did not differ between the two cohorts, specifically, there was no significant difference in the number of injuries that occurred at home in pandemic versus non-pandemic circumstances. Besides a decrease in the number of falls, the distribution of mechanisms of injury remained similar during the COVID-19 study period. There was no difference in self-inflicted injuries observed. Prehospital interventions remained similar during the COVID-19 pandemic compared to one year prior. Specifically, prehospital intubation did not differ between the two cohorts. The rate of COVID-19 positively tested HEMS personnel was 23.1%. Physicians who tested positive were unable to take call for a mean of 25 days (range 8–53). Conclusion: A decrease in the number of deployments and increase in the number of cancelled missions was observed during the COVID-19 study period. No major differences in operational- and injury characteristics were found for HEMS and HEMS-ambulance dispatches between the initial phase of the COVID-19 pandemic in the Netherlands and the same period one year prior. These findings highlight the importance of continued operability of the HEMS, even during pandemic circumstances. Level of evidence: III, retrospective comparative study

    Preventable death in trauma: A systematic review on definition and classification

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    Purpose: Trauma-related preventable death (TRPD) has been used to assess the management and quality of trauma care worldwide. However, due to differences in terminology and application, the definition of TRPD lacks validity. The aim of this systematic review is to present an overview of current literature and establish a designated definition of TRPD to improve the assessment of quality of trauma care. Methods: A search was conducted in PubMed, Embase, the Cochrane Library and the Web of Science Core Collection. Including studies regarding TRPD, published between January 1, 1990, and April 6, 2021. Studies were assessed on the use of a definition of TRPD, injury severity scoring tool and panel review. Results: In total, 3,614 articles were identified, 68 were selected for analysis. The definition of TRPD was divided in four categories: I. Clinical definition based on panel review or expert opinion (TRPD, trauma-related potentially preventable death, trauma-related non-preventable death), II. An algorithm (injury severity score (ISS), trauma and injury severity score (TRISS), probability of survival (Ps)), III. Clinical definition completed with an algorithm, IV. Other. Almost 85% of the articles used a clinical definition in some extend; solely clinical up to an additional algorithm. A total of 27 studies used injury severity scoring tools of which the ISS and TRISS were the most frequently reported algorithms. Over 77% of the panels included trauma surgeons, 90% included other specialist; 61% emergency medicine physicians, 46% forensic pathologists and 43% nurses. Conclusion: The definition of TRPD is not unambiguous in literature and should be based on a clinical definition completed with a trauma prediction algorithm such as the TRISS. TRPD panels should include a trauma surgeon, anesthesiologist, emergency physician, neurologist, and forensic pathologist

    Long-term Emergency Department Visits and Readmissions After Laparoscopic Roux-en-Y Gastric Bypass: a Systematic Review

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    Purpose: There is considerable evidence on short-term outcomes after laparoscopic Roux-en-Y gastric bypass (LRYGB), but data on long-term outcome is scarce, especially on postoperative emergency department (ED) visits and readmissions. We aim to systematically review evidence on the incidence, indications, and risk factors of ED visits and readmissions beyond 30 days after LRYGB. Materials and Methods: A systematic search in PubMed, Scopus, Embase.com, Cochrane Library, and PsycINFO was performed. All studies reporting ED visits and readmissions > 30 days after LRYGB, with ≥ 50 patients, were included. PRISMA statement was used and the Newcastle-Ottawa Scale for quality assessment. Results: Twenty articles were included. Six studies reported on ED visits (n = 2818) and 19 on readmissions (n = 276,543). The rate of patients with an ED visit within 90 days after surgery ranged from 3.9 to 32.6%. ED visits at 1, 2, and 3 years occurred in 25.6%, 30.0%, and 31.1% of patients. Readmissions within 90 days and at 1-year follow-up ranged from 4.1 to 20.5% and 4.75 to 16.6%, respectively. Readmission was 29% at 2 years and 23.9% at 4.2 years of follow-up. The most common reason for ED visits and readmissions was abdominal pain. Conclusion: Emergency department visits and readmissions have been reported in up to almost one in three patients on the long-term after LRYGB. Both are mainly indicated for abdominal pain. The report on indications and risk factors is very concise. A better understanding of ED visits and readmissions after LRYGB is warranted to improve long-term care, in particular for patients with abdominal pains
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