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Growth in the immediate postnatal period for extremely low birth weight (ELBW, birth weight < 1000 g) infants is an important topic in neonatal medicine. The goal is to ensure adequate postnatal growth and to minimize complications resulting from suboptimal growth. Past efforts have focused on postnatal nutrition as well as on minimizing comorbidities. It has not been systematically assessed whether antenatal factors play a role in postnatal growth. In this report, we conducted a retrospective study on 91 maternal–neonatal pairs. We prospectively collected maternal and neonatal demographic data, neonatal nutrition in the first 7 days of life and after enteral nutrition is fully established, comorbidity data, as well as weight data from birth to 50 weeks corrected gestational age. We developed a linear mixed-effects model to examine the role of placental insufficiency, as defined by fetal Doppler studies, in postnatal weight z-score trajectory over time in the ELBW population. We relied on Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) for model selection. Interestingly, the selected model included a quadratic term of time and a placental insufficiency-by-time interaction term. In a covariate analysis, AIC and BIC both favored a model that included calories intake in the first 7 days of life and the total duration of antibiotics as fixed-effects, but not their interaction terms with time. Overall, we demonstrated for the first time that placental insufficiency, an antenatal factor, is a major determinant of postnatal weight trajectory in the ELBW population. Prospective studies are warranted to confirm our findings.
Forty-eight different Ag–Al–Zr ternary alloys were prepared in various compositions to determine the metallic glass region in the Ag–Al–Zr ternary system. Experimental results indicated that the metallic glass region in the Ag–Al–Zr ternary system is Ag20–30Al10–30Zr50–60. The Ag20Al30Zr50 and Ag30Al20Zr50 alloys are supposed to have the best glass-forming ability in the Ag–Al–Zr ternary system. The phase equilibria of the Ag–Al–Zr ternary system at 773 K (500 °C) were investigated and compared with the metallic glass region results in the Ag–Al–Zr ternary system. Ternary isothermal sections of the Ag–Al–Zr system at 773 K (500 °C) were established and two ternary intermetallic phases were observed in this isothermal section.
Effective perioperative hand antisepsis is crucial for the safety of patients and medical staff in surgical rooms. The antimicrobial effectiveness of different antiseptic methods, including conventional hand scrubs and waterless hand rubs, has not been well evaluated.
DESIGN, SETTING, AND PARTICIPANTS
A randomized controlled trial was conducted to investigate the effectiveness of the 3 antiseptic methods among surgical staff of Taipei Medical University—Shuang Ho Hospital. For each method used, a group of 80 participants was enrolled.
Surgical hand cleansing with conventional 10% povidone–iodine scrub, conventional 4% chlorhexidine scrub, or waterless hand rub (1% chlorhexidine gluconate and 61% ethyl alcohol).
Colony-forming unit (CFU) counts were collected using the hand imprinting method before and after disinfection and after surgery. After surgical hand disinfection, the mean CFU counts of the conventional chlorhexidine (0.5±0.2, P<0.01) and waterless hand rub groups (1.4±0.7, P<0.05) were significantly lower than that of the conventional povidone group (4.3±1.3). No significant difference was observed in the mean CFU count among the groups after surgery. Similar results were obtained when preexisting differences before disinfection were considered in the analysis of covariance. Furthermore, multivariate regression indicated that the antiseptic method (P=.0036), but not other variables, predicted the mean CFU count.
Conventional chlorhexidine scrub and waterless hand rub were superior to a conventional povidone–iodine product in bacterial inhibition. We recommend using conventional chlorhexidine scrub as a standard method for perioperative hand antisepsis. Waterless hand rub may be used if the higher cost is affordable.
To investigate the reciprocal relationship between unhealthy eating behaviours and depressive symptoms from childhood to adolescence.
Unhealthy eating behaviours were measured by the frequencies of eating foods with excess salt, sugar or fat in the past week. Depressive symptoms in the past two weeks were measured using a seven-item scale. Hierarchical linear growth models were used to analyse longitudinal associations between unhealthy eating behaviours and depressive symptoms. Time-fixed variables (sex, parents’ education level and household monthly income) and time-varying variables (parents’ marital status, family activities, body weight, vegetable or fruit consumption, exercising and smoking) were controlled for.
The Child and Adolescent Behaviors in Long-Term Evolution study, which commenced in 2001 and has annual follow-up.
Students (n 2630) followed from 2nd grade (8 years old in 2002) to 11th grade.
The frequency of unhealthy eating behaviours in the previous year and the difference between the frequency in the previous and successive year were positively associated with the initiation and growth rate of depressive symptoms. Depressive symptoms in the previous year and the difference in depressive symptoms between the previous and successive year were positively associated with the initial state and growth rate of unhealthy eating behaviours.
Our results suggest a reciprocal relationship between depressive symptoms and unhealthy eating behaviours. This relationship should be considered when developing programmes targeting depressive symptoms and unhealthy diet in children and adolescents.
Bacillus pasteurii was used as synthesis director for the formation of hollow cylinder and helical NiO micro/nanostructure under urea hydrolysis conditions. Bacteria were capable of precipitating nickel product from nickel solution by metabolic processes. An appropriate amount of both water and bacterial solution were required to precipitate the nickel product in good yield. The average crystallite size of NiO was 11.45 nm and lengths of the cylinder and helices were non-uniform (~2–7 µm) and were varied with bacterial body structure template. The present study demonstrates a feasibility of synthesizing bacteria-guided metal oxide crystals for various functional applications.
Worldwide, the number of individuals with dementia is growing in an epidemic manner, with an estimated 35.6 million people affected in 2010 (Prince et al., 2013). With the population aging in Asia, dementia care will become a major public health challenge in this region in the coming decades. Over half of the patients with dementia in the world will live in Asia by 2030. In China alone, a recent review of dementia studies showed that there were 9.2 million dementia patients in 2010 (Chan et al., 2013). These figures are staggering. In many Asian countries, dementia is regarded as a shameful illness, and the local terms for dementia are derogatory. Dementia carries a stigma that may lead to patients’ reluctance in seeking treatment and delay in diagnosis. In addition, local names for dementia frequently conjure up pictures of severe stage of dementia, and may lead to therapeutic nihilism, discouraging mental health professionals from working with elderly patients with dementia. As Asia faces the challenges of a rapidly aging population and provisions of care for growing number of dementia patients, change in local names for dementia has become an issue of attention.
The potential relationship between anaesthesia, surgery and onset of
dementia remains elusive.
To determine whether the risk of dementia increases after surgery with
anaesthesia, and to evaluate possible associations among age, mode of
anaesthesia, type of surgery and risk of dementia.
The study cohort comprised patients aged 50 years and older who were
anaesthetised for the first time since 1995 between 1 January 2004 and 31
December 2007, and a control group of randomly selected patients matched
for age and gender. Patients were followed until 31 December 2010 to
identify the emergence of dementia.
Relative to the control group, patients who underwent anaesthesia and
surgery exhibited an increased risk of dementia (hazard ratio = 1.99) and
a reduced mean interval to dementia diagnosis. The risk of dementia
increased in patients who received intravenous or intramuscular
anaesthesia, regional anaesthesia and general anaesthesia.
The results of our nationwide, population-based study suggest that
patients who undergo anaesthesia and surgery may be at increased risk of
Background: Executive dysfunction is not uncommon in patients with amnestic mild cognitive impairment (aMCI). This study aimed to investigate the applicability of executive function tests (EFTs) in aMCI as an aid in establishing the diagnosis of multi-domain MCI.
Methods: One hundred and twenty (120) aMCI patients, 126 Alzheimer's disease (AD) patients, and 100 normal controls were enrolled. The EFTs evaluated included the trail making test, digit backward span, Stroop color–word test, and design fluency and category fluency tests.
Results: Of the aMCI participants, 66% exhibited impairment in at least one EFT. Among the five selected EFTs, the category fluency test was the most discriminative in detecting executive dysfunction between patients with aMCI (standardized β = 0.264) or AD (standardized β = 0.361) with the controls, followed by the Stroop test. The performance of aMCI patients with two or more impaired EFTs was significantly different from those of controls but not from those of AD patients.
Conclusion: In the clinical setting, aMCI patients who fail in two or more EFTs may represent a unique population with multi-domain MCI that require close follow-up.
Spectral clustering is a technique for finding group structure in data. It makes use of the spectrum of the data similarity matrix to perform dimensionality reduction for clustering in fewer dimensions. Spectral clustering algorithms have been shown to be more effective in finding clusters than traditional algorithms such as k-means. However, spectral clustering suffers from a scalability problem in both memory use and computation time when the size of a dataset is large. To perform clustering on large datasets, in this work, we parallelize both memory use and computation using MapReduce and MPI. Through an empirical study on a document set of 534,135 instances and a photo set of 2,121,863 images, we show that our parallel algorithm can effectively handle large problems.
Clustering is one of the most important subfields of machine learning and data mining tasks. In the last decade, spectral clustering (e.g., Shi and Malik, 2000; Meila and Shi, 2000; Fowlkes et al., 2004), motivated by normalized graph cut, has attracted much attention. Unlike traditional partition-based clustering, spectral clustering exploits a pairwise data similarity matrix. It has been shown to be more effective than traditional methods such as k-means, which considers only the similarity between instances and k centroids (Ng, Jordan, and Weiss, 2001).Because of its effectiveness, spectral clustering has been widely used in several areas such as information retrieval and computer vision (e.g., Dhillon, 2001; Xu, Liu, and Gong, 2003; Shi and Malik, 2000; Yu and Shi, 2003).
Polyaniline nanofiber (PANF) was synthesized using interfacial polymerization and was mixed with aqueous solution of poly(vinyl alcohol) (PVA) to form PANF–PVA binaries. The PANF suspension in water could be stabilized by PVA for more than 3 months due to the hydrogen bonding interaction between PANF and PVA. The specific characteristics of PANF–PVA films was checked by scanning electron microscopy, conductivity measurement, thermogravimetric analysis, Fourier transform infrared spectroscopy, and cyclic voltammetry. The composite film contained 25 wt% PVA (PANF–PVA25) casting at 105 °C was found to have a porous structure and good conductivity. The presence of hydrogen bonding interaction between PANF and PVA improves the electroactivity and electroactive stability of PANF–PVA25 for electrochemical applications. However, an ether linkage between PANF and PVA polymer chain was also found as casting the PANF–PVA film at 200 °C, which is unfavorable for electrochemical applications.
Most biological materials are hierarchically structured composites that often possess exceptional mechanical properties. We show that nanoindentation can be a powerful tool for understanding the structure‑mechanical property relationship of biological materials and illustrate this for fish teeth and scales, not heretofore investigated at the nanoscale. Piranha and shark teeth consist of enameloid and dentin. Nanoindentation measurements show that the reduced modulus and hardness of enameloid are 4‑5 times higher than those of dentin. Arapaima scales are multilayered composites that consist of mineralized collagen fibers. The external layer is more highly mineralized, resulting in a higher modulus and hardness compared with the internal layer. Alligator gar scales are composed of a highly mineralized external ganoin layer and an internal bony layer. Similar design strategies, gradient structures, and a hard external layer backed by a more compliant inner layer are exhibited by fish teeth and scales and seem to fulfill their functional purposes.
Epitaxial α-Fe films have been grown on Si(111) substrates at 30 and 320°C by electron beam evaporation in an ultra high vacuum environment to a thickness between a few hundred and several thousand Angstroms. Conventional θ – 2θ x-ray diffraction and transmission electron microscopy show that the α-Fe films are oriented with the Fe(1ll) plane parallel to the Si(111) plane and with the Fe direction parallel to the Si direction in the plane of the substrate.
In this work, we study the thermal stability and interaction between SiOF and Cu. Blanket SiOF films with various F concentration were deposited by PE-CVD. A dielectric constant as low as 3.2 was obtained. Copper were deposited on these SiOF and a series of post-deposition anneal were performed. Dielectric constant of SiOF was measured after deposition and again after anneal. AES and SIMS depth profile are utilized to determine the interdiffusion between Cu and SiOF under different annealing conditions. Breakdown voltage and dielectric constant were determined form C-V and I-V measurement using a MIS ( Cu/ SiOF/ p-Si) diode. This results of leakage current measurement and flat band shift measurement suggest that the fluorine in the SiOF film will retard the cu diffusion.
Selective tungsten chemical vapor deposition (W-CVD) is one of the most attractive technique for filling deep submicron contact hole and via hole for the ULSI application. In this work, we firstly find out the anomalous selective W growth for the contact hole. The tungsten only nucleates from the side ring of the contact hole bottom. Several predeposition treatments prior to W growth can improve this anomalous feature and excellently selective W growth can be achieved. Auger electron spectroscopy (AES) is utilized to investigate the interface of Si/W. A model has been proposed to explain this anomalous selective tungsten growth.
In this study, nanoporous silica films were prepared from the poly(hydrogen silsesquioxane)(HSSQ) and a templating agent. Three different kinds of the HSSQ with different molecular weight and Si-OH end group content were prepared through the variation of the water/triethoxysilane ratio or pH. The templaing agent for generating nanopore was triphenylsilanol (TPS). The experimental results of refractive index, dielectric constant, and FE-SEM supported the formation of the nano-size pores in the prepared silica films. The dielectric constant of the prepared nanoporous thin films could be reduced form 2.89 (porosity: 12%) to 1.85 (porosity: 58%) by increasing the added TPS. The surface roughness of the prepared nanoporous silica film in comparison with the film thickness was less than 1%. For successful generating small and uniform nanopore in the film, low molecular weight or high Si-OH content of the prepared HSSQ would be required. The current approach is useful for preparing new kinds of low dielectric constant materials.
We applied the deactivation treatments to p-type single crystalline silicon solar cells for deactivating the recombination-active boron-oxygen complex. The methods we used include thermal annealing treatment, capacitively couple plasma (CCP) treatment, and plasma immersion ion implantation (PIII) treatment. The results showed that all the deactivation treatments were working and the energy transfer efficiency (Eff) was thereby increased by more than 1% absolute compared to the degraded state base on the increasing of the open-circular voltage (Voc) and short-current density (Jsc). The CCP deactivated treatment got better efficiencies than PIII treatment because the PIII treatment damaged the surface of solar cells. After the forming gas treatment, the samples could be improved to close to the PIII samples due to the surface damage repairing. However, the increased efficiency could not be kept and would be degraded again after illumination.
The interfacial reactions in Sn-0.7wt%Cu/ENIG SUS304 couples at 240, 255, and 270 °C are examined in this study. The Ni-containing ternary Cu6Sn5 phase is formed at the Ni/liquid interface in the early reaction stage then it detaches massively from the SUS304 substrate and splits into two layers in the molten solder as the reaction time increases. This phase finally disintegrates and disappears. The square pillar-shaped FeSn2 phase is found on top of the SUS304 substrate when the Cu6Sn5 layer detaches. The reaction phase formation, detachment, and split mechanisms are proposed. The spalling phenomenon is reviewed and discussed. The growth mechanism of the FeSn2 phase obeys the parabolic law, and the activation energy is determined to be 112.5 KJ/mol.
Previous scholars considered competence a ‘fuzzy concept’ and addressed confusions such as ‘competency vs. competence’ and ‘competence vs. core competence’. However, the issue ‘What is the essence of employee competence?’ remains unclear. By inference, the essence of competence is addressed in adoption of an organization's sustained competitive advantage viewpoint different from the traditional viewpoint of enhancing individual employability. This paper contends that employee competence is strategically driven by organizational core competence. Psychologically, employee competence and organizational core competence are similar and linked in terms of person–organization fit and person–job fit. A contextual competence framework is established enlightening the essence of employee competence and redefines competence as a ‘temporary asset’ rooted in the interactively organizational context. Contextual variables including shared values, mutual trust and mutual investment bolster the alignment between employee competence and organizational core competence and develop employee competence as firm-specific, thus becoming a source for sustained organizational competitive advantage.