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141.
Taylor H. Gerry; Dietrich Ann; Nuss Kathryn; Wright Martha; Rusin Jerome; Bangert Barbara; Minich Nori; Yeates Keith Owen 《Canadian Metallurgical Quarterly》2010,24(2):148
To investigate postconcussive symptoms (PCS) following pediatric mild traumatic brain injury (mTBI), 8- to 15-year-old children with mTBI (n = 186) and a comparison group with uncomplicated orthopedic injuries (OI, n = 99) were recruited from two emergency departments. Parent and child ratings of PCS and symptom counts were obtained within 3 weeks after injury (baseline) and at 1, 3, and 12 months postinjury. The mTBI group also completed magnetic resonance imaging at baseline. Group differences were examined using growth modeling, controlling for age at injury, sex, socioeconomic status, and (for parent-based measures) preinjury symptom levels. Relative to the OI group, the mTBI group had higher ratings of somatic PCS and parent counts of PCS at the initial assessments, but higher parent ratings of cognitive PCS and child counts of PCS throughout follow-up. Higher levels of PCS in the mTBI group were associated with motor-vehicle-related trauma, loss of consciousness, neuroimaging abnormalities, and hospitalization. The findings validate both transient and persistent PCS in children with mTBI and document associations of symptoms with injury and noninjury factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
142.
The effect of TiO2 dopant on phase stability, microstructural evolution and room temperature mechanical properties of 8 mol% yttria-stabilized cubic zirconia (8Y-CSZ) was studied. The results show that TiO2 (up to 10 wt%) can be dissolved in solid solution in the zirconia matrix. When the dopant amount is less than 5 wt%, TiO2 doped 8Y-CSZ remains single phase cubic zirconia. Increased additions of TiO2 destabilize the cubic phase and cause the formation of tetragonal zirconia with a resultant microstructure consisting of large cubic zirconia grains and small tetragonal zirconia grains. EDS analyses show that yttria is partitioned between these two types of grains. The solubility of TiO2 is the highest for cubic grains which also have higher yttria concentrations. Room temperature mechanical property measurements show that hardness does not change significantly with additions of TiO2, but fracture toughness is more than doubled for 10 wt% TiO2 doped 8Y-CSZ. 相似文献
143.
Thomas J. Taylor Oussama Elbjeirami Charlotte N. Burress Mitsukimi Tsunoda Martha I. Bodine Mohammad A. Omary François P. Gabbaï 《Journal of Inorganic and Organometallic Polymers and Materials》2008,18(1):175-179
The interaction of the Hg(II) derivatives bis(pentafluoro)phenyl mercury (1), (pentafluoro)phenyl mercury chloride (2) and trimeric perfluoro-ortho-phenylene mercury (3) with tolane (diphenylacetylene) in CH2Cl2 leads to the formation of [1·tolane], [2
2·tolane], and [3·tolane·CH2Cl2]. These adducts have been characterized by elemental analysis, X-ray crystallography, and luminescence spectroscopy. In the
solid state of these adducts, the tolane molecules interact with the molecules of 1, 2 and 3 via secondary Hg–π interactions and arene–fluoroarene interactions. As a result of an external mercury heavy atom effect,
adducts [1·tolane] and [2
2·tolane] are phosphorescent at room temperature. 相似文献
144.
Microbial quality assessment of household greywater 总被引:1,自引:0,他引:1
O'Toole J Sinclair M Malawaraarachchi M Hamilton A Barker SF Leder K 《Water research》2012,46(13):4301-4313
A monitoring program was undertaken to assess the microbial quality of greywater collected from 93 typical households in Melbourne, Australia. A total of 185 samples, comprising 75 washing machine wash, 74 washing machine rinse and 36 bathroom samples were analysed for the faecal indicator Escherichia coli. Of these, 104 were also analysed for genetic markers of pathogenic E coli and 111 for norovirus (genogroups GI and GII), enterovirus and rotavirus using RT-PCR. Enteric viruses were detected in 20 out of the 111 (18%) samples comprising 16 washing machine wash water and 4 bathroom samples. Eight (7%) samples were positive for enterovirus, twelve (11%) for norovirus genogroup GI, one (1%) for norovirus genogroup GII and another (1%) for rotavirus. Two washing machine samples contained more than one virus. Typical pathogenic E. coli were detected in 3 out of 104 (3%) samples and atypical enteropathogenic E. coli in 11 (11%) of samples. Levels of indicator E. coli were highly variable and the presence of E. coli was not associated with the presence of human enteric viruses in greywater. There was also little correlation between reported gastrointestinal illness in households and detection of pathogens in greywater. 相似文献
145.
The survival of Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes was determined on almonds and pistachios held at typical storage temperatures. Almond kernels and inshell pistachios were inoculated with four- to six-strain cocktails of nalidixic acid-resistant Salmonella, E. coli O157:H7, or L. monocytogenes at 6 log CFU/g and then dried for 72 h. After drying, inoculated nuts were stored at -19, 4, or 24°C for up to 12 months. During the initial drying period after inoculation, levels of all pathogens declined by 1 to -log CFU/g on both almonds and pistachios. During storage, moisture content (4.8%) and water activity (0.4) of the almonds and pistachios were consistent at -19°C; increased slowly to 6% and 0.6, respectively, at 4°C; and fluctuated from 4 to 5% and 0.3 to 0.5 at 24°C, respectively. Every 1 or 2 months, levels of each pathogen were enumerated by plating; samples were enriched when levels fell below the limit of detection. No reduction in population level was observed at -19 or 4°C for either pathogen, with the exception of E. coli O157:H7-inoculated almonds stored at 4°C (decline of 0.09 log CFU/g/month). At 24°C, initial rates of decline were 0.20, 0.60, and 0.71 log CFU/g/month on almonds and 0.15, 0.35, and 0.86 log CFU/g/month on pistachios for Salmonella, E. coli O157:H7, and L. monocytogenes, respectively, but distinct tailing of the survival curves was noted for both E. coli O157:H7 and L. monocytogenes. 相似文献
146.
Martha Johanna Sepúlveda Wang Jiang Chau Guy Gogniat Marius Strum 《Analog Integrated Circuits and Signal Processing》2012,73(3):851-860
Current SoC design trends are characterized by the integration of larger amount of IPs targeting a wide range of application fields. Such multi-application systems are constrained by a set of requirements. In such scenario network-on-chips (NoC) are becoming more important as the on-chip communication structure. Designing an optimal NoC for satisfying the requirements of each individual application requires the specification of a large set of configuration parameters leading to a wide solution space. It has been shown that IP mapping is one of the most critical parameters in NoC design, strongly influencing the SoC performance. IP mapping has been solved for single application systems using single and multi-objective optimization algorithms. In this paper we propose the use of a multi-objective adaptive immune algorithm (M2AIA), an evolutionary approach to solve the multi-application NoC mapping problem. Latency and power consumption were adopted as the target multi-objective functions. To compare the efficiency of our approach, our results are compared with those of the genetic and branch and bound multi-objective mapping algorithms. We tested 11 well-known benchmarks, including random and real applications, and combines up to 8 applications at the same SoC. The experimental results showed that the M2AIA decreases in average the power consumption and the latency 27.3 and 42.1 % compared to the branch and bound approach and 29.3 and 36.1 % over the genetic approach. 相似文献
147.
Tiele M. Rizzetti Maiara P. de Souza Osmar D. Prestes Martha B. Adaime Renato Zanella 《Food Analytical Methods》2017,10(4):854-864
A simple and rapid sample preparation method was developed and validated for multi-class analysis of veterinary drug residues in bovine kidney and liver. Sample preparation procedure was performed using acetonitrile and trichloroacetic acid for protein precipitation followed by ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) analysis. The proposed method was validated according to the criteria of the Commission Decision 2002/657/EC evaluating linearity, selectivity, accuracy and precision, determination limit (CCα), and detection capacity (CCβ). Linearity presented r 2 ≥ 0.99 for all the target compounds, and recoveries ranged from 80 to 110 % with RSD ≤17 % for intra- and inter-day assay. Values of CCα and CCβ ranged from 11 to 1096 and from 12 to 1191 μg kg?1, respectively. The proposed sample preparation followed by UHPLC-MS/MS analysis was suitable for the determination of 20 veterinary drug residues in bovine kidney and liver in routine analysis. Method applicability was evaluated using commercial samples. 相似文献
148.
Many individuals who meet criteria for borderline personality disorder have histories of childhood trauma that may have contributed to their difficulty regulating affect. Dialectical behavioral therapy focuses on helping these patients to regulate emotional states and achieve behavioral control in Stage 1 so they can tolerate therapy that is focused on trauma and emotional experiencing in a Stage 2 treatment. Although there are effective, empirically validated treatments for posttraumatic stress disorder and its subclinical presentation, there are also a significant number of patients who find these treatments difficult to tolerate. The author discusses coupling dialectical behavioral therapy, an evidence-based therapy, with internal family systems, a therapy that is both clinically promising and compatible with dialectical behavioral therapy, as a Stage 2 therapy for trauma patients who avoid other modes of treatment. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
149.
Spencer Kevin M.; Nestor Paul G.; Valdman Olga; Niznikiewicz Margaret A.; Shenton Martha E.; McCarley Robert W. 《Canadian Metallurgical Quarterly》2011,25(1):76
Objective: While attentional functions are usually found to be impaired in schizophrenia, a review of the literature on the orienting of spatial attention in schizophrenia suggested that voluntary attentional orienting in response to a valid cue might be paradoxically enhanced. We tested this hypothesis with orienting tasks involving the cued detection of a laterally presented target stimulus. Method: Subjects were chronic schizophrenia patients (SZ) and matched healthy control subjects (HC). In Experiment 1 (15 SZ, 16 HC), cues were endogenous (arrows) and could be valid (100% predictive) or neutral with respect to the subsequent target position. In Experiment 2 (16 SZ, 16 HC), subjects performed a standard orienting task with unpredictive exogenous cues (brightening of the target boxes). Results: In Experiment 1, SZ showed a larger attentional facilitation effect on reaction time than HC. In Experiment 2, no clear sign of enhanced attentional facilitation was found in SZ. Conclusions: The voluntary, facilitatory shifting of spatial attention may be relatively enhanced in individuals with schizophrenia in comparison to healthy individuals. This effect bears resemblance to other relative enhancements of information processing in schizophrenia such as saccade speed and semantic priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
150.
McCurry DA Kamundi M Fayette M Wafula F Dimitrov N 《ACS applied materials & interfaces》2011,3(11):4459-4468
In an effort to decrease the high cost associated with the design, testing, and production of electrocatalysts, a completely electrochemical scheme has been developed to deposit and platinize a nanoporous Au (NPG) based catalyst for formic acid oxidation. The proposed route enables synthesis of an alternative to the most established, nanoparticles based catalysts and addresses issues of the latter associated with either contamination inherent from the synthetic route or poor adhesion to the supporting electrode. The synthetic protocol includes as a first step, electrochemical codeposition of a Au((1-x))Ag(x) alloy in a thiosulfate based electrolyte followed by selective electrochemical dissolution (dealloying) of Ag as the less noble metal, that generates an ultrathin and preferably continuous porous structure featuring thickness of less than 20 nm. NPG is then functionalized with Pt (no thicker than 1 nm) by surface limited redox replacement (SLRR) of underpotentially deposited Pb layer to form Pt-NPG. SLRR ensures complete coverage of the surface with Pt, believed to spread evenly over the NPG matrix. Testing of the catalyst at a proof-of-concept level demonstrates its high catalytic activity toward formic acid oxidation. Current densities of 40-50 mA cm(-2) and mass activities of 1-3 A.mg(-1) (of combined Pt-Au catalyst) have been observed and the Pt-NPG thin films have lasted over 2600 cycles in standard formic acid oxidation testing. 相似文献