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31.
Renal tubular dysgenesis (RTD) is a very rare malformation, only 24 cases having been described. We present the case of twins born after 28 weeks gestation to a newly-arrived Ethiopian immigrant in whom oligohydramnios was diagnosed when she was admitted. 1 twin had developed polyhydramnios, died before birth and was born with hydrops fetalis. The other newborn suffered from pulmonary distress and anuria, and died 2 days after birth. At autopsy there were no apparent changes in the kidneys or urinary tract, but histological examination showed absence of proximal convoluted tubules. This was attributed to RTD and confirmed by histochemical examination.  相似文献   
32.
Studies of the mechanical and optical properties of undrawn polypropylene fibres by annealing and drawing were performed. The optical properties and strain produced in polypropylene fibres at different conditions were measured interferometrically at room temperature. It was found that as the draw ratio of the fibre increased, its birefringence, Δna, increased at a constant rate, and then nearly levelled off. The refractive index, n , and polarizability, p , increased with different draw ratios; but for fibres annealed at 70 and 100°C, there were no acceptable variations. For fibres annealed at 130°C, n and p increased compared to those fibres annealed at 70 and 100°C. An empirical formula has been suggested to explain the relationship between the cross-sectional area of polypropylene fibres with the draw ratio, and the constants of this formula have been determined. The effect of annealing on the refractive index profile of undrawn polypropylene fibres, before and after thermal treatment, was studied. The strain optical coefficient and the Poisson's ratio were calculated over different draw ratios. The results obtained clarify the effect of annealing time and temperature with different draw ratios on the optical behaviour of polypropylene fibres. Microinterferograms are given for illustration.  相似文献   
33.
Aframework for understanding source monitoring and relevant empirical evidence is described, and several related phenomena are discussed: old–new recognition, indirect tests, eyewitness testimony, misattributed familiarity, cryptomnesia, and incorporation of fiction into fact. Disruptions in source monitoring (e.g., from confabulation, amnesia, and aging) and the brain regions that are involved are also considered, and source monitoring within a general memory architecture is discussed. It is argued that source monitoring is based on qualities of experience resulting from combinations of perceptual and reflective processes, usually requires relatively differentiated phenomenal experience, and involves attributions varying in deliberateness. These judgments evaluate information according to flexible criteria and are subject to error and disruption. Furthermore, diencephalic and temporal regions may play different roles in source monitoring than do frontal regions of the brain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
34.
The effect of ginger extract (GE), as a milk coagulant, was investigated on the physicochemical, proteolysis, textural profiles and sensory properties of whey-less cheese containing quinoa germ powder (QGP; 0, 3, 6 and 9%) during storage. The results showed that with increasing QGP, the dry matter, fat, soluble nitrogen at pH 4.6 and free tryptophan and tryptophan amino acids increased and protein content decreased. Consequently, it is suggested that using 6% quinoa germ in the production of whey-less cheese made by GE as a coagulant can give the most desired product with no adverse effects on the quality and sensory properties.  相似文献   
35.
In May 2013, sediment samples were collected from five stations in the Straits of Johor, near the southern tip of Peninsular Malaysia, in order to evaluate the distribution and sources of polycyclic aromatic hydrocarbons (PAHs). The concentrations of 16 United States Environmental Protection Agency PAHs varied from 650.5 to 1441.2 ng g ?1 dry weight (dw) with a mean value of 985.5 ng g ?1 dw. PAHs can be classified as moderate level pollution in the collected samples. When comparing PAHs in this study with that of the sediment quality guidelines (SQGs), it was found that the total PAHs, low molecular weight (LMW), and high molecular weight (HMW) PAHs might incur minimal adverse biological effects. The diagnostic ratios of individual PAHs indicated both petrogenic and pyrogenic origins with predominantly pyrogenic sources, the findings of which are further supported by the results from principal component analysis (PCA). The PCA results reveal contributions of 44.44%, 32.3%, and 18.96% for traffic-related, coal combustion, and petroleum-related products, respectively. These findings indicate that the effective monitoring and significant improvement resulting from the implementation of environmental regulations in Malaysia might have caused a shift in the source of petroleum hydrocarbons in the Straits of Johor's aquatic ecosystems from petrogenic to pyrogenic origins.  相似文献   
36.
Abstract

In this study feedback control is applied to control the free vibration response of an isotropic truncated conical shell embedded with magnetostrictive layers. Classical shell theory is applied to derive the shell vibration equations. The results are derived based on the Galerkin method and the results are compared with published results and the results of finite element software in order to determine the accuracy of using method. The influence of several parameters such as the thickness of magnetostrictive layers, control gain, length and radius of the large edge of the shell on the vibration suppression of fundamental frequency is determined.  相似文献   
37.
38.
Water Resources Management - Water resource systems are under enormous pressures globally. To diagnose and quantify potential vulnerabilities, effective modeling tools are required to represent the...  相似文献   
39.
As intended by its name, physically unclonable functions (PUFs) are considered as an ultimate solution to deal with insecure storage, hardware counterfeiting, and many other security problems. However, many different successful attacks have already revealed vulnerabilities of certain digital intrinsic PUFs. This paper demonstrates that legacy arbiter PUF and its popular extended versions (i.e., feed-forward and XOR-enhanced) can be completely and linearly characterized by means of photonic emission analysis. Our experimental setup is capable of measuring every PUF internal delay with a resolution of 6 ps. Due to this resolution, we indeed require only the theoretical minimum number of linear independent equations (i.e., physical measurements) to directly solve the underlying inhomogeneous linear system. Moreover, it is not required to know the actual PUF responses for our physical delay extraction. We present our practical results for an arbiter PUF implementation on a complex programmable logic device manufactured with a 180 nm process. Finally, we give an insight into photonic emission analysis of arbiter PUF on smaller chip architectures by performing experiments on a field programmable gate array manufactured with a 60 nm process.  相似文献   
40.
The mechanical properties of fat–oil mixtures are dictated by the morphology of the fat crystal network, which in turn is strongly affected by the processing conditions. In this work the effect of uniform (linear) cooling rates on the size and shape of tribehenin (fat) clusters in isopropyl myristate (oil) was studied. The state of the fat–oil mixtures was comprehensively analyzed by establishing pseudo‐phase diagrams via visual observations, brightfield and polarization microscopy at various cooling rates and fat concentrations. The microstructure of the constituent fat clusters undergo a shape transition from bundles of needles at low cooling rates to spherical clusters at high cooling rates. The network structures formed with these different shaped fat clusters were examined using rheology. At a given cooling rate, the storage modulus (G?) of fat–oil mixtures versus fat concentration followed a power law relationship. For a given fat concentration, the fat crystal networks comprising of bundles of needles showed higher G? values as compared to fat networks made of spherical clusters. While the fractal dimension of networks cooled at different cooling rates varied over a small range of 2.78–2.86, considerable change in the pre‐exponential factor (γ) was observed. The results show the critical importance of processing conditions on the shape and size of fat clusters and its impact on the rheological properties of the fat crystal network.  相似文献   
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