597 research outputs found
Benchmarking CMOS Adder Structures
Adders are key components in digital signal processing,
performing not only addition operations, but also many other functions such
as subtraction, multiplication and division. The difficulty with comparing
adder structures from different sources is that quite often different
implementation techniques and technologies have been used in the design. A
second problem that arises when comparing structures is that several
different measurement techniques may have been used, the target
technology can differ and key features may not been measured. Therefore,
this paper will investigate the seven most commonly used adder structures
in a way which makes them directly comparable. This is achieved by
implementing all adder structures with the same technology, the same level
of abstraction and then using the same set of tools to determine the features
of each of the designs
Benchmarking CMOS Adder Structures
Adders are key components in digital signal processing,
performing not only addition operations, but also many other functions such
as subtraction, multiplication and division. The difficulty with comparing
adder structures from different sources is that quite often different
implementation techniques and technologies have been used in the design. A
second problem that arises when comparing structures is that several
different measurement techniques may have been used, the target
technology can differ and key features may not been measured. Therefore,
this paper will investigate the seven most commonly used adder structures
in a way which makes them directly comparable. This is achieved by
implementing all adder structures with the same technology, the same level
of abstraction and then using the same set of tools to determine the features
of each of the designs
Methane and nitrous oxide fluxes in two coastal wetlands in the northeastern Gulf of Bothnia, Baltic Sea
Nitrous oxide fluxes from tropical peat with different disturbance history and management
Peer reviewe
Mixed Reality-Based Simulator for Training on Imageless Navigation Skills in Total Hip Replacement Procedures
Imageless navigation systems (INS) in orthopaedics have been used to improve the outcomes of several orthopaedic procedures such as total hip replacement [1, 2]. However, the increased surgical times and the associate learning curve discourage surgeons from using navigation systems in their theatres [2]. This paper presents a Mixed Reality (MR) simulator that helps surgeons acquire the infrared based navigation skills before performing it in reality. A group of 7 hip surgeons tried the application, expressing their satisfaction with all the features and confirmed that the simulator represents a cheaper and faster option to train surgeons in the use of INS than the current learning methods
Comatose With Basilar Artery Occlusion : Still Odds of Favorable Outcome With Recanalization Therapy
Background: Around 30-60% of patients with basilar artery occlusion (BAO) present with coma, which is often considered as a hallmark of poor prognosis. Aim: To examine factors that will help predict outcomes in patients with BAO comatose on admission. Methods: A total of 312 patients with angiography-proven BAO were analyzed. Comas were assessed as Glasgow Coma Scale (GCS) of Results: In total, 103/259 (39.8%) of BAO patients were comatose on admission. Factors associated with acute coma were higher age, coronary artery disease, convulsions, extent of early ischemia by posterior circulation Acute Stroke Prognosis Early CT Score (pc-ASPECTS) < 8, absence of patent posterior collateral vasculature, and occlusion over multiple segments of BA. A total of 21/103 (20.4%) of comatose patients had a favorable outcome (mRS 0-3), and 12/103 (11.7%) had a good outcome (mRS 0-2). Factors associated with a favorable outcome in comatose BAO patients were younger age (p = 0.010), less extensive baseline ischemia (p = 0.027), recanalization (p = 0.013), and avoiding symptomatic intracranial hemorrhage (sICH) (p = 0.038). Factors associated with the poorest outcome or death (mRS 5-6) were older age (p = 0.001), diabetes (p = 0.022), atrial fibrillation (p = 0.016), lower median GCS [4 (IQR 3.6) vs. 6 (5-8); p = 0.006], pc-ASPECTS < 8 (p = 0.003), unsuccessful recanalization (p = 0.006), and sICH (p = 0.010). Futile recanalization (mRS 4-6) was significantly more common in comatose patients (49.4 vs. 18.5%, p < 0.001). Conclusions: One in five BAO patients with acute coma had a favorable outcome. Older patients with cardiovascular comorbidities and already existing ischemic lesions before reperfusion therapies tended to have a poor prognosis, especially if no recanalization is achieved and sICH occurred.Peer reviewe
Denitrification in the River Estuaries of the Northern Baltic Sea
Estuaries have been suggested to have an important role in reducing the nitrogen load transported to the sea. We measured denitrification rates in six estuaries of the northern Baltic Sea. Four of them were river mouths in the Bothnian Bay (northern Gulf of Bothnia), and two were estuary bays, one in the Archipelago Sea (southern Gulf of Bothnia) and the other in the Gulf of Finland. Denitrification rates in the four river mouths varied between 330 and 905 mu mol N m(-2) d(-1). The estuary bays at the Archipelago Sea and the Gulf of Bothnia had denitrification rates from 90 mu mol N m(-2) d(-1) to 910 mu mol N m(-2) d(-1) and from 230 mu mol N m(-2) d(-1) to 320 mu mol N m(-2) d(-1), respectively. Denitrification removed 3.6-9.0% of the total nitrogen loading in the river mouths and in the estuary bay in the Gulf of Finland, where the residence times were short. In the estuary bay with a long residence time, in the Archipelago Sea, up to 4.5% of nitrate loading and 19% of nitrogen loading were removed before entering the sea. According to our results, the sediments of the fast-flowing rivers and them estuary areas with short residence times have a limited capacity to reduce the nitrogen load to the Baltic Sea.Estuaries have been suggested to have an important role in reducing the nitrogen load transported to the sea. We measured denitrification rates in six estuaries of the northern Baltic Sea. Four of them were river mouths in the Bothnian Bay (northern Gulf of Bothnia), and two were estuary bays, one in the Archipelago Sea (southern Gulf of Bothnia) and the other in the Gulf of Finland. Denitrification rates in the four river mouths varied between 330 and 905 mu mol N m(-2) d(-1). The estuary bays at the Archipelago Sea and the Gulf of Bothnia had denitrification rates from 90 mu mol N m(-2) d(-1) to 910 mu mol N m(-2) d(-1) and from 230 mu mol N m(-2) d(-1) to 320 mu mol N m(-2) d(-1), respectively. Denitrification removed 3.6-9.0% of the total nitrogen loading in the river mouths and in the estuary bay in the Gulf of Finland, where the residence times were short. In the estuary bay with a long residence time, in the Archipelago Sea, up to 4.5% of nitrate loading and 19% of nitrogen loading were removed before entering the sea. According to our results, the sediments of the fast-flowing rivers and them estuary areas with short residence times have a limited capacity to reduce the nitrogen load to the Baltic Sea.Estuaries have been suggested to have an important role in reducing the nitrogen load transported to the sea. We measured denitrification rates in six estuaries of the northern Baltic Sea. Four of them were river mouths in the Bothnian Bay (northern Gulf of Bothnia), and two were estuary bays, one in the Archipelago Sea (southern Gulf of Bothnia) and the other in the Gulf of Finland. Denitrification rates in the four river mouths varied between 330 and 905 mu mol N m(-2) d(-1). The estuary bays at the Archipelago Sea and the Gulf of Bothnia had denitrification rates from 90 mu mol N m(-2) d(-1) to 910 mu mol N m(-2) d(-1) and from 230 mu mol N m(-2) d(-1) to 320 mu mol N m(-2) d(-1), respectively. Denitrification removed 3.6-9.0% of the total nitrogen loading in the river mouths and in the estuary bay in the Gulf of Finland, where the residence times were short. In the estuary bay with a long residence time, in the Archipelago Sea, up to 4.5% of nitrate loading and 19% of nitrogen loading were removed before entering the sea. According to our results, the sediments of the fast-flowing rivers and them estuary areas with short residence times have a limited capacity to reduce the nitrogen load to the Baltic Sea.Peer reviewe
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Effect of Inhaled Xenon on Cerebral White Matter Damage in Comatose Survivors of Out-of-Hospital Cardiac Arrest: A Randomized Clinical Trial
IMPORTANCE: Evidence from preclinical models indicates that xenon gas can prevent the development of cerebral damage after acute global hypoxic-ischemic brain injury but, thus far, these putative neuroprotective properties have not been reported in human studies. OBJECTIVE: To determine the effect of inhaled xenon on ischemic white matter damage assessed with magnetic resonance imaging (MRI). DESIGN, SETTING, AND PARTICIPANTS: A randomized single-blind phase 2 clinical drug trial conducted between August 2009 and March 2015 at 2 multipurpose intensive care units in Finland. One hundred ten comatose patients (aged 24-76 years) who had experienced out-of-hospital cardiac arrest were randomized. INTERVENTIONS: Patients were randomly assigned to receive either inhaled xenon combined with hypothermia (33°C) for 24 hours (n = 55 in the xenon group) or hypothermia treatment alone (n = 55 in the control group). MAIN OUTCOMES AND MEASURES: The primary end point was cerebral white matter damage as evaluated by fractional anisotropy from diffusion tensor MRI scheduled to be performed between 36 and 52 hours after cardiac arrest. Secondary end points included neurological outcome assessed using the modified Rankin Scale (score 0 [no symptoms] through 6 [death]) and mortality at 6 months. RESULTS: Among the 110 randomized patients (mean age, 61.5 years; 80 men [72.7%]), all completed the study. There were MRI data from 97 patients (88.2%) a median of 53 hours (interquartile range [IQR], 47-64 hours) after cardiac arrest. The mean global fractional anisotropy values were 0.433 (SD, 0.028) in the xenon group and 0.419 (SD, 0.033) in the control group. The age-, sex-, and site-adjusted mean global fractional anisotropy value was 3.8% higher (95% CI, 1.1%-6.4%) in the xenon group (adjusted mean difference, 0.016 [95% CI, 0.005-0.027], P = .006). At 6 months, 75 patients (68.2%) were alive. Secondary end points at 6 months did not reveal statistically significant differences between the groups. In ordinal analysis of the modified Rankin Scale, the median (IQR) value was 1 (1-6) in the xenon group and 1 (0-6) in the control group (median difference, 0 [95% CI, 0-0]; P = .68). The 6-month mortality rate was 27.3% (15/55) in the xenon group and 34.5% (19/55) in the control group (adjusted hazard ratio, 0.49 [95% CI, 0.23-1.01]; P = .053). CONCLUSIONS AND RELEVANCE: Among comatose survivors of out-of-hospital cardiac arrest, inhaled xenon combined with hypothermia compared with hypothermia alone resulted in less white matter damage as measured by fractional anisotropy of diffusion tensor MRI. However, there was no statistically significant difference in neurological outcomes or mortality at 6 months. These preliminary findings require further evaluation in an adequately powered clinical trial designed to assess clinical outcomes associated with inhaled xenon among survivors of out-of-hospital cardiac arrest. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00879892
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