2,559 research outputs found
A low power clock generator with adaptive inter-phase charge balancing for variability compensation in 40-nm CMOS
Power dissipation besides chip area is still one main optimization issue
in high performance CMOS design. Regarding high throughput building blocks
for digital signal processing architectures
which are optimized down to the physical
level a complementary two-phase clocking scheme (CTPC) is often
advantageous concerning ATE-efficiency.
The clock
system dissipates a significant part of overall power up to more than 50%
in some applications.
<br><br>
One efficient power saving strategy for
CTPC signal generation is the charge balancing technique.
To achieve high efficiency with this approach
a careful optimization of timing relations within the control
is inevitable.
<br><br>
However, as in modern CMOS processes device variations
increase,
timing relations between
sensitive control signals
can be affected seriously.
In order to compensate for the influence of global and local variations in this
work, an adaptive control system for charge balancing in a CTPC generator
is presented. An adjustment for the degree of charge recycling is performed
in each clock cycle.
In the case of insufficient recycling
the delay elements which define duration and timing position of
the recycling pulse are corrected by switchable timing units.
<br><br>
In a benchmark with the conventional clock generation system,
a power reduction gain
of up to 24.7% could be achieved. This means saving in power
of more than 12% for a complete number-crunching building block
Usability and feasibility of consumer-facing technology to reduce unsafe medication use by older adults
Background
Mobile health technology can improve medication safety for older adults, for instance, by educating patients about the risks associated with anticholinergic medication use.
Objective
This study's objective was to test the usability and feasibility of Brain Buddy, a consumer-facing mobile health technology designed to inform and empower older adults to consider the risks and benefits of anticholinergics.
Methods
Twenty-three primary care patients aged ≥60 years and using anticholinergic medications participated in summative, task-based usability testing of Brain Buddy. Self-report usability was assessed by the System Usability Scale and performance-based usability data were collected for each task through observation. A subset of 17 participants contributed data on feasibility, assessed by self-reported attitudes (feeling informed) and behaviors (speaking to a physician), with confirmation following a physician visit.
Results
Overall usability was acceptable or better, with 100% of participants completing each Brain Buddy task and a mean System Usability Scale score of 78.8, corresponding to “Good” to “Excellent” usability. Observed usability issues included higher rates of errors, hesitations, and need for assistance on three tasks, particularly those requiring data entry. Among participants contributing to feasibility data, 100% felt better informed after using Brain Buddy and 94% planned to speak to their physician about their anticholinergic related risk. On follow-up, 82% reported having spoken to their physician, a rate independently confirmed by physicians.
Conclusion
Consumer-facing technology can be a low-cost, scalable intervention to improve older adults’ medication safety, by informing and empowering patients. User-centered design and evaluation with demographically heterogeneous clinical samples uncovers correctable usability issues and confirms the value of interventions targeting consumers as agents in shared decision making and behavior change
SDSS Observations of Kuiper Belt Objects: Colors and Variability
Colors of Trans Neptunian Objects (TNOs) are used to study the evolutionary
processes of bodies in the outskirts of the Solar System, and to test theories
regarding their origin. Here I describe a search for serendipitous Sloan
Digital Sky Survey (SDSS) observations of known TNOs and Centaurs. I present a
catalog of SDSS photometry, colors and astrometry of 388 measurements of 42
outer Solar-System objects. I find a weak evidence, at the ~2-sigma level (per
trial), for a correlation between the g-r color and inclination of scattered
disk objects and hot classical KBOs. I find a correlation between the g-r color
and the angular momentum in the z direction of all the objects in this sample.
Light curves as a function of phase angle are constructed for 13 objects. The
steepness of the slopes of these light curves suggests that the coherent
backscatter mechanism plays a major role in the reflectivity of outer
Solar-System small objects at small phase angles. I find a weak evidence for an
anti-correlation, significant at the 2-sigma confidence level (per trial),
between the g-band phase angle slope parameter and the semi-major axis, as well
as the aphelion distance, of these objects. I discuss the origin of this
possible correlation and argue that if this correlation is real it probably
indicates that "Sedna"-like objects have a different origin than other classes
of TNOs. Finally, I identify several objects with large variability amplitudes
(abridged).Comment: 8 pages, ApJ in pres
Synthesis of structurally diverse major groove DNA interstrand crosslinks using three different aldehyde precursors
DNA interstrand crosslinks (ICLs) are extremely cytotoxic lesions that block essential cellular processes, such as replication and transcription. Crosslinking agents are widely used in cancer chemotherapy and form an array of structurally diverse ICLs. Despite the clinical success of these agents, resistance of tumors to crosslinking agents, for example, through repair of these lesions by the cellular machinery remains a problem. We have previously reported the synthesis of site-specific ICLs mimicking those formed by nitrogen mustards to facilitate the studies of cellular responses to ICL formation. Here we extend these efforts and report the synthesis of structurally diverse major groove ICLs that induce severe, little or no distortion in the DNA. Our approach employs the incorporation of aldehyde precursors of different lengths into complementary strands and ICL formation using a double reductive amination with a variety of amines. Our studies provide insight into the structure and reactivity parameters of ICL formation by double reductive amination and yield a set of diverse ICLs that will be invaluable for exploring structure-activity relationships in ICL repairope
АСР процесса горения в топке котла при реализации безмазутной растопки
In the last years laser-induced breakdown spectroscopy was introduced in various industrial applications. Automated inspection machines were developed capable to operate under harsh ambient conditions. As an example laser-induced breakdown spectroscopy-based inspection machines for the identification testing of fittings and tubes made of high-alloy steel will be presented. Within an inspection time of 2 seconds 100 spectra are gained yielding the signals of 12 elemental lines to identify more than 30 different high-alloy steel grades in order to prevent material mix-ups at the end of a production line prior to packaging and dispatch. More than 1.5 million products have been inspected within the last 5 years in routine operation. Requirements, concepts and design of such machines will be discussed considering the issues on analytical resolution and system monitoring. For the first time a data set of more than 10(exp 8) laser-induced breakdown spectroscopy measurements has become available, giving insight into the long-term behavior of the system performance. First evaluations of this data demonstrate the influence of laser power, sample position and temperature on the spectroscopic signals and the system state. Future demands on next-generation inspection machines based on laser-induced breakdown spectroscopy will be defined
Simulations of the High-Energy Beam-Transport (HEBT) section at FRANZ
The neutron source FRANZ (Frankfurter Neutronenquelle am
Stern-Gerlach-Zentrum), which is currently under construction, will be the neutron source with the highest intensity in the nuclear-astrophysically relevant energy
region. The TraceWin code was used to design the High-Energy Beam-Transport section with regard to the experimental requirements at different target positions
Relationship between African-American Race and Delirium in the Intensive Care Unit
Objective
Delirium is a highly prevalent syndrome of acute brain dysfunction among critically ill patients that has been linked to multiple risk factors such as age, pre-existing cognitive impairment, and use of sedatives; but to date the relationship between race and delirium is unclear. We conducted this study to identify whether African-American race is a risk factor for developing ICU delirium.
Design
A prospective cohort study.
Setting
Medical and Surgical ICUs of a university affiliated, safety-net hospital in Indianapolis, Indiana.
Patients
2087 consecutive admissions with 1008 African-Americans admitted to the ICU services from May 2009 to August 2012.
Interventions
None
Measurements and Main Results
Incident delirium defined as first positive Confusion Assessment Method for the ICU (CAM-ICU) result after an initial negative CAM-ICU; and prevalent delirium defined as positive CAM-ICU on first CAM-ICU assessment. The overall incident delirium rate in African-Americans was 8.7% compared to 10.4% in Caucasians (P: 0.26). The prevalent delirium rate was 14% in both African-Americans and Caucasians (P: 0.95). Significant age and race interactions were detected for incident delirium (P: 0.02), but not for prevalent delirium (P: 0.3). The hazard ratio for incident delirium for African-Americans in the 18–49 years age group compared to Caucasians of similar age was 0.4 (0.1– 0.9). The hazard and odds ratios for incident and prevalent delirium in other groups were not different.
Conclusions
African-American race does not confer any additional risk for developing incident or prevalent delirium in the ICU. Instead younger African-Americans tend to have lower rates of incident delirium compared to similar age Caucasians
SDSS J1553+0056: A BALQSO mimicking a Lyman-break galaxy
Using the UVES echelle spectrograph at the ESO VLT we obtained
high-resolution (R = 40 000) spectra of the object SDSS J1553+0056, which has
been identified in the literature alternatively as a high-redshift quasar or as
a Lyman-break galaxy (LBG). Although low-resolution spectra of SDSS J1553+0056
closely resemble those of LBGs, our high-resolution spectra allow us to
identify this object unambiguously as a LoBAL quasar, probably belonging to the
rare FeLoBALQSO class. Based on our spectrum we discuss how misidentifications
of such objects from low-resolution spectra can be avoided.Comment: 5 pages, 3 figures, accepted for publication in A&
Deprescribing in the Pharmacologic Management of Delirium (de-PMD): A Randomized Trial in the Intensive Care Unit
OBJECTIVE:
Benzodiazepines and anticholinergics are risk factors for delirium in the intensive care unit (ICU). We tested the impact of a deprescribing intervention on short-term delirium outcomes.
DESIGN:
Multi-site randomized clinical trial
SETTING:
ICU’s of three large hospitals
PARTICIPANTS:
Two hundred adults aged ≥ 18 years admitted to an ICU with delirium according to the Richmond Agitation Severity Scale and the Confusion Assessment Method for the ICU (CAM-ICU). Participants had a contraindication to haloperidol (seizure disorder or prolonged QT interval) or preference against haloperidol as a treatment for delirium, and were excluded for serious mental illness, stroke, pregnancy or alcohol withdrawal. Participants were randomized to a deprescribing intervention or usual care. The intervention included electronic alerts combined with pharmacist support to deprescribe anticholinergics and benzodiazepines.
MEASUREMENTS:
Primary outcomes were delirium duration measured by the CAM-ICU, and severity measured by the Delirium Rating Scale Revised-98 (DRS-R-98) and the CAM-ICU-7; secondary outcomes included adverse events and mortality.
RESULTS:
Participants had a mean age of 61.8 (standard deviation: 14.3) years, 59% female, and 52% African American with no significant differences in baseline characteristics between groups. No differences between groups were identified in the number exposed to anticholinergics (p=0.219) or benzodiazepines (p=0.566), the median total anticholinergic score (p=0.282), or the median total benzodiazepine dose in lorazepam equivalents (p=0.501). Neither median delirium/coma-free days (p=0.361) nor median change in delirium severity scores (p=0.582 for DRS-R-98; p=0.333 for CAM-ICU-7) were different between groups. No differences in adverse events or mortality were identified. CONCLUSIONS:
When added to state-of-the-art clinical services, this deprescribing intervention had no impact on medication use in ICU participants. Given the age of the population, results of clinical outcomes may not be easily extrapolated to older adults. Nonetheless, improved approaches for deprescribing or preventing anticholinergics and benzodiazepines should be developed to determine the impact on delirium outcomes
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