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This thesis aims to address how Chinese transnational family members involved in the 'caregiving triangle' - migrant parents, left-behind children and guardians (Suarez-Orozco et al., 2002) - navigate new media environments to negotiate their family roles and maintain kinship ties. Acknowledging the structural 'asymmetrical reciprocity' (Baldassar & Merla, 2014) of transnational families - which derives from the intersection of internal factors (including family obligation, expectations and norms) and external transnational socioeconomic contexts - this study examines the power dynamics and care circulation through mediated communication among family members across borders. To this end, this study employs a three-year multi-sited ethnography, including participant observation, in-depth interviews and online ethnography of Chinese labour migrants in Britain (mainly clandestine and low-skilled workers) and their family members, conducted between 2015 and 2018. The findings highlight the varied forms of agency and challenges experienced by migrant and non-migrant family members embedded in different social-technical contexts. Notable among these are: the transnational family structure; migration status and generation; Chinese patriarchal ideology; and the socio-economic discrepancies between Britain and (rural) China, which contribute to the shaping of mediated transnational communication. The adoption of communication technology in transnational family life has minimized the geographical and temporal constraints that divide these dispersed family members and enhanced the 'reciprocity' between them (including childrearing collaboration between migrant parents and guardians and strengthened intergenerational solidarity between migrant parents and children). However, it has also exacerbated the 'asymmetry' of transnational families, such as increased gendered parenting burdens and parental surveillance over left-behind children. This study argues that this mediated 'asymmetrical reciprocity' is subject to constant negotiation, as a consequence of unconfined translocal family settings along with the affordances of communication technologies.

In this thesis I explore the current end-of-life care provision as experienced by older people with advanced cancer in three distinct care settings in Yunnan China: a hospice, an inpatient palliative care ward and a self-help organisation. In particular, I focus on the role of "hope" at the end of life, hope having emerged as a significant aspect of participant's experiences. I took a "multiple-embedded case study" approach, employing mainly qualitative interviewing and observation to capture the richness and complexity of the experience of end-of-life care in different settings. The findings show that mainstream health care for advanced cancer in China focused on curative western medicine and failed to alleviate prevalent pain and symptoms. Specialised palliative/end-of-life care services adapted from the western palliative care model contributed mainly to relieving cancer pain and symptoms. "Total care for the whole person" - the core of the palliative care philosophy, was an aggregate of the resources located in the family, health care and the broader sociocultural environment. The study revealed the nature of hope as essentially affirming life in all circumstances and as situated and fostered in a "hierarchical social and cultural ecology of hope" (Feudtner 2005, p. S23) comprising an individual, his or her family, care providers and other physical, social and cultural elements. The fostering of hope, as a resource at the end of life, has implications for improving care and support at multiple levels - personal, interpersonal and social and cultural.

In this thesis, we propose several cross-layer operation aided schemes conceived for wireless networks. Cross layer design may overcome the disadvantages of the network's layered architecture, where layering is most typically represented by the Transport Control Protocol (TCP) / Internet Protocol (IP) suite. We invoke Fountain codes for protecting file transfer at the application layer, since they are suitable for erasure channels. They are also often referred to as rateless codes. When implementing Fountain code aided file transfer, the file will be firstly partitioned into a number of blocks, each of which contains K packets. Fountain codes randomly select several packets from a block and then combine them using exclusive- OR additions for generating an encoded packet. The encoding continues until all blocks are successfully received. Considering an 802.11 Wireless Local Area Network (WLAN) scenario, the packet size has to be appropriately chosen, since there exists a trade-off between the packet size and the transmission efficiency, which is defined as the number of primary information bits to the total number of all transmitted bits including headers, control packets and retransmitted replicas. In order to find the optimum packet size, the transmission efficiency is formulated as a function of the Packet Loss Ratio (PLR) at the application layer and of the total load imposed by a single packet. The PLR at the application layer is related both to the packet size, as well as to the 802.11 MAC retransmission mechanism and to the modulation scheme adopted by the physical layer. Apart from its source data, the total load imposed by an information packet also contains the control packets of the 802.11 Media Access Control (MAC) protocol such as the Request To Send (RTS) / Clear To Send (CTS) messages, the retransmitted replicas and the Acknowledgement (ACK) messages. According to these relations, the transmission effciency may finally be expressed as a function of packet size. Based on the numerical analysis of this function, the optimum packet size may be determined. Our simulation results confirmed that indeed the highest transmission efficiency may be achieved, when using the optimum packet size. Since turbo codes are capable of achieving near capacity performance, they may be successfully combined with Hybrid Automatic Repeat reQuest (HARQ) schemes. In this thesis, the classic Twin Component Turbo Codes (TCTCs) are extended to Multiple Component Turbo Codes (MCTCs). In order to apply classic two-dimensional Extrinsic Information Transfer (EXIT) charts for analyzing them, we divided an N-component MCTC into two logical parts. This partitioning was necessary, because otherwise an N-component scheme would require an N-dimensional EXIT chart. One of the parts is constituted by an individual Bahl, Cocke, Jelinek and Raviv (BCJR) decoder, while the other so-called composite decoder consists of the remaining (N-1) components. The EXIT charts visualized the extrinsic information exchange between these two logical parts of MCTCs. Aided by this partitioning technique, we may find the so-called `open tunnel SNR threshold' for MCTCs, which is defined as the minimum SNR for which the EXIT chart at the specific coding rate used has an open tunnel. It may be used as a metric to compare the achievable performance to the Discreteinput Continuous-output Memoryless Channel's (DCMC) capacity. Our simulation results showed that the achievable performance of MCTCs is closer to the DCMC capacity than that of non-systematic TCTCs, but a bit further than that of systematic TCTCs, if generator polynomials having an arbitrary memory length - and hence complexity - are considered. However, for the lowest-memory octally represented polynomial (2; 3)o, which implies having the lowest possible complexity, MCTCs outperform non-systematic and systematic TCTCs. Furthermore, MCTC aided HARQ schemes using the polynomial of (2; 3)o exhibit significantly better PLRs and throughput performances than systematic as well as non-systematic TCTC aided HARQ schemes using the same polynomial. If systematic TCTC aided HARQ schemes relying on the polynomial of (17; 15)o are used as benchmarkers, MCTC aided HARQ schemes may significantly reduce the complexity, without a substantial degradation of the PLR and throughput. When combining turbo codes with HARQ, the associated complexity becomes a critical issue, since iterative decoding is immediately activated after each transmission. In order to reduce the associated complexity, an Early Stopping (ES) strategy was proposed in this thesis to substitute the fixed number of BCJR operations invoked for each iterative decoding. By observing the EXIT charts of turbo codes, we note that the extrinsic information increases along the decoding trajectory of an open or closed tunnel. The ES aided MCTC HARQ scheme curtails iterative decoding, when the Mutual Information (MI) increase becomes less than a given threshold. This threshold was determined by an off-line training in order to achieve a trade-off between the throughput and complexity. Our simulation results verified that the complexity of MCTC aided HARQ schemes may be reduced by as much as 80%, compared to that of systematic TCTC aided HARQ schemes using a fixed number of 10 BCJR operations. Moreover, the complexity of turbo coded HARQ schemes may be further reduced by our Look-Up Table (LUT) based Deferred Iteration (DI) method. The DI method delays the iterative decoding until the receiver estimates that it has received sufficient information for successful decoding, which may be represented by the emergence of an open tunnel in the EXIT chart corresponding to all received replicas. Therefore, the specific MI that a `just' open tunnel appears when combining all previous (i-1) MIs will be the threshold that has to be satisfed by the ith reception. More specifically, if the MI received during the ith reception is higher than this threshold, the EXIT tunnel is deemed to be open and hence the iterative decoding is triggered. Otherwise, iterative decoding will be disabled when the tunnel is deemed to be closed. This reduces the complexity. The LUT stores all possible MI thresholds for N-component MCTCs, which results in a large storage requirement, if N becomes high. Hence, an efficient LUT design was also proposed in this thesis. Our simulation results demonstrated the achievable complexity reduction may be as high as 50%, compared to the schemes operating without the DI method.

This thesis examines the Chinese economy by focusing on three issues: convergence, total factor productivity (TFP) and industrial growth. The study of convergence was undertaken using a panel of China’s 28 provinces over the period 1979-2004. The share of physical capital in China’s output was found to be 0.23 and the provinces were found to converge at a rate of 5.6 per cent per annum. To calculate the growth of TFP for China’s 29 provinces in this period, the non-parametric Malmquist index approach was employed in the analysis. It was found that, for China as a whole, TFP grew at a rate of 2.75 per cent per annum, which accounted for 30.02 per cent of its real GDP growth. The aim of the study of industrial growth was to examine the correlates of growth of 26 industries in 9 provinces of the Eastern Zone of China over the period 2001 to 2005. The analysis identified the dynamic externalities and province-specific externalities that were important to province-industrial growth. It also discovered an evident trend in the period under study of conditional convergence within the 26 industries in the Eastern Zone.

The basic mechanisms regulating the function of the bladder and urethra, under both normal and abnormal conditions, are still incompletely understood, and consequently, many treatments are both empirical and unsatisfactory. This thesis examines the physiology and pharmacology of lower urinary tract smooth muscles from rabbit, pig and cat, utilising isometric tension recording of strips of muscle taken from the lower urinary tract of these three species. Abundant cholinergic innervation of the bladder in all three species was demonstrated. Alpha-adrenoceptors predominated in the urethra, whereas responses to beta-adrenoceptors predominated in the bladder body, though alpha-adrenoceptors were present in the posterior detrusor of the rabbit. The present studies confirmed that non-adrenergic, non-cholinergic transmitters are involved in the mechanism regulating function of the lower urinary tract. Contractile responses were seen in response to application of ATP and 5-HT. The 5-HT response was diminished by atropine and α,β-methylene ATP. A combination of these drugs diminished the contractile response more than either alone. Evidence is presented for the presynaptic action of 5-HT, causing release of acetylcholine and a non-adrenergic, non-cholinergic transmitter in the rabbit lower urinary tract, probably mediated via the 5-HT3 receptor, identified by the use of several putative 5-HT antagonists. This thesis suggests that high KCl-induced contraction is due to initiation of depolarization of the smooth muscles membrane, triggering the opening of Ca channels, Ca entry and subsequent contraction. High KCl-induced relaxation in the pig urethra is unlikely to occur by stimulation of inhibitory nerves or by activation of the Na pump. The results of the histological studies agree with the pharmacological study in the conclusion that the autonomic innervation of the lower urinary tract of small mammals contains non-adrenergic, non-cholinergic innervation in addition to sympathetic and parasympathetic nerves. The development of specific agonists and antagonists to the receptors mediating the responses may play an important role in the future treatment of abnormal micturition.

Operating systems rely heavily on access control mechanisms to achieve security goals and defend against remote and local attacks. The complexities of modern access control mechanisms and the scale of policy configurations are often overwhelming to system administrators and software developers. Therefore, mis-configurations are common, and the security consequences are serious. It is critical to have models and tools to analyze thoroughly the effectiveness of access control policies in operating systems and to eliminate configuration errors. In this dissertation, we propose an approach to systematically analyze access control policies in operating systems. The effectiveness of a policy can be evaluated under attack scenarios. An attack scenario consists of the initial resources an attacker has and the attacker's objective. Attacks under an attack scenario are encoded in a host attack graph. Compared to existing solutions, our approach is more comprehensive and does not rely on manually defined attack patterns. Based on the model, a tool called VulSAN is implemented to analyze policies in Linux systems, and a tool called WACCA is implemented to analyze policies in Windows systems. We analyze policies in Ubuntu, Fedora, SUSE Linux and Windows Vista. We discuss the results and show the possibilities to improve the quality of protection. The results are also used to compare the effectiveness of SELinux and AppArmor policies in a version of Ubuntu Linux. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

The purpose of this research is to characterize the sustainability of Selenastrum capricornutum (S.Cap.) under the stress of the Cd2+ -Cu2+ system and analyze its effectivity of removing both metal ions. The microalgae are representative algae whose resistance to and uptake of metals can be extensible to other algae. The goal of this research is to use experimental and statistical method to analyze whether the algae is benefited from the antagonistic effect of Cd2+ -Cu2+ joint toxicity and increase the removal-ability under different pH, hardness and containment concentration. The results of this work show that the adsorption rate of Cd2+ and Cu2+ is deceased in a binary-stress system comparing to single Cd2+ stress and single Cu stress. The highest metal removal percentage decreases from 61.78% to 44.41% for Cd2+ and from 98.66% to 68.00% for Cu ions. The algae show the potential of removal during the 96 hr experiment period. The algae are acidic domesticated prior, but the removal rates are comparably lower in a more acidic solution(pH3.5) than a more neural solution (pH 6.5). The hardness of water seems to have a minor influence on the metal removal process.

Antifouling materials that can effectively resist protein adsorption, cell adhesion and microorganism growth, are critical for a wide range of fundamental and industrial applications from ship coatings, biomedical implants, bioseparation, biosensors, and carriers for drug and gene delivery. However, only a few noufouling polymers (

The genetic basis underlying how organisms adapt to different environments and evolve new life style is a central issue of molecular evolution. The evolution of aerobic fermentation in yeasts is one of those good examples. So far the underlying genetic basis of this phenotypic evolution remains unclear. Gene duplication, as a primary source of materials for evolutionary novelties, has long been thought to play an important role in the adaptation of organisms to their environments. It was hypothesized that whole genome duplication (WGD) led to the development of this efficient fermentative life style. However, it remains unclear how the WGD genes are regulated during the switch of energy metabolism, an issue which should be the essence of the "WGD-Fermentation hypothesis". In this study, I first used a genome-wide expression dataset during robust metabolic oscillation in response to oxygen in budding yeast (Tu et al. 2005) to investigate the distribution of WGD genes in metabolic cycle. An enrichment of WGD genes was found underlying the physiological response of S. cerevisiae to oxygen change. Our results provided new evidence for the WGD-Fermentation hypothesis. In the next, I explored in more detail about what were the important WGD genes that contributed greatly to the evolution of aerobic fermentation. Two WGD genes are brought to the front to study this issue due to their importance on regulating energy metabolism. One of the two genes is pyruvate kinase (PYK), and the other is the target of rapamycin (TOR). In both cases, I revealed positive correlations between the copy number of these genes and the strength of aerobic fermentation on a yeast phylogenetic tree, which implies that gene duplication events of PYK and TOR are possible to facilitate the evolution of aerobic fermentation. In the PYK experiment, I found that yeasts with higher capabilities on the allosteric regulation of PYK tend to have higher fermentation abilities. I then assumed that the strengthened allosteric regulation of PYK after gene duplication might be important in the development of fermentation lifestyle in yeast. Further study on T403E mutant which is defect in allosteric regulation on PYK supported this assumption, as T403E mutant showed raised oxidative phosphorylation and decreased fermentation rate compared with the control. In the TOR experiment, I mimicked the TOR gene duplication during yeast history and doubled the TOR gene in a Crabtree-negative yeast K.lactis. I observed that the fermentation ratio in the doubled TOR mutant was significantly increased compared with the control, which supported that TOR gene duplication contributed greatly to the evolution of fermentative life style. In the view of the similar features shared by fermenting yeast and cancer cells on aerobic fermentation, our studies on PYK and TOR may shed lights on the mechanism how the Warburg effect is regulated in tumor cells.

The high frame rate imaging method is expected to be a leading technology of ultrasound imaging in the future. In this dissertation, the high frame rate imaging method is further studied, and the applications of the high frame rate imaging method are explored. To achieve the real-time 3D ultrasound imaging with a full 2D ultrasound transducer in a high frame rate imaging system, a new model of an ultrasound probe is proposed using the data compression technique. Raw echo data is first compressed by the JPEG algorithm, and then transferred to the image processing system with a reasonable number of wires in the cable connecting an ultrasound probe and the image processing system. The results show that the quality of the image after the JPEG data compression technique is still close to the image before the data compression. In addition, the effects of phase aberration and noise on the high frame rate imaging method is quantitatively studied. The parameters of energy ratio and sidelobe ratio are proposed and combined with the traditional -6-dB lateral resolution to analyze the image quality over the entire imaging area. The results show that the high frame rate imaging method has higher lateralresolution than the D&S imaging method, and the high frame imaging method is influenced less by the phase aberration and noise than the D&S imaging method. The results also indicate that the proposed parameters of energy ratio and sidelobe ratio could potentially be used for the correction of phase aberration. Finally, the high frame rate imaging method is applied to the strain and strain rate imaging of soft tissues. The two dimensional speckle tracking technique is used to measure the values of strain and strain rate. In the speckle tracking technique, the algorithm of the summation of absolute difference is used to search matched blocks between two consecutive images. Both simulation and experimentation studies were conducted to verify the method of applying the high frame rate imaging method to estimate the strain and strain rate. It is found that the high frame rate imaging method can be used to accurately measure the strain and strain rate. Considering the long computation time of speckle tracking, a new kernel using two crossing diagonal lines is proposed. The results of the preliminary study show that it is possible for the new kernel to reduce the computation time while retaining the accuracy of the estimation of strain and strain rate various imaging methods.

The study on the relationship between sports and cities has proliferated among academics. However, research is mostly focused on developed countries such as the United States and Europe. What kind of impacts do sports events have on Chinese cities? Do sports-events influence post-Mao China differently than developed countries? Assessing the impacts that sporting mega-events have on Guangzhou, which will host the 16th Asian Game in 2010, this research reveals that China’s governments are the key actor in the process of bidding for and hosting mega-sports events. Cities in China have used this strategy to stimulate new district development instead of urban redevelopment. The city governments in China are pursuing sporting mega-events for infrastructure improvement rather than economic issues. The construction of new stadiums and infrastructure, environmental improvement, city image improvement and district development are positive outcomes; however, there is a lack of economic assessment. There is a need for the city to cooperate with the private sector, adopt public participation and to develop a cost-effective use of sports facilities after the sporting mega-events are over.

This thesis presents our design and implementation of a real-time network monitoring program for DeSiDeRaTa, an existing resource management system. This monitor will assist DeSiDeRaTa in maintaining an acceptable Quality of Service (QoS) for groups of real-time applications by reporting the communication delays caused by inadequate network bandwidth. The network monitoring application we developed uses SNMP and network topology information gleaned from the DeSiDeRaTa application specification files. Algorithms were designed to compute network bandwidth utilization of each real-time communication path. Preliminary experiments have been run on a local area network environment. The results demonstrated the accuracy of these measurements and the correct implementation of the network monitoring program.

To study peptide absorption in chickens, an intestinal peptide transporter cDNA (cPepT1) was isolated from a chicken cDNA library. The cDNA was 2,914-bp and encoded a protein of 714 amino acid residues. Twenty-three di-, tri-, and tetra-peptides were used for functional analysis of cPepT1 in Xenopus oocytes and Chinese hamster ovary (CHO) cells. For most di- and tripeptides tested, the Kt was in the micromolar range, except Lys-Lys and Lys-Trp-Lys. Northern analysis demonstrated that cPepT1 is expressed strongly in the small intestine, and at lower levels in kidney and cecum. These results demonstrated the presence and functions of a peptide transporter in chickens. cPepT1 mRNA abundance was evaluated in response to developmental and dietary regulations. In Experiment 1, eggs at incubation day 18 (E18) and Cobb chicks after hatch (d 0) were sampled before treatments. Three groups of chicks were fed diets containing 12, 18, or 24% crude protein (CP). Feed intake of chicks fed the 18 or 24% CP diets was restricted to that of chicks fed the 12% CP diet. In Experiment 2, a fourth group with free access to the 24% CP diet was added. cPepT1 mRNA abundance was quantified from northern blots. By d 0, there was a 50-fold increase in cPepT1 mRNA abundance compared with E 18. In chicks fed the 12% CP diet, cPepT1 mRNA abundance decreased throughout the 35 d. Chicks fed 18 or 24% CP diets showed an increase in cPepT1 mRNA abundance with time. In chicks with free access to the 24% CP diet, cPepT1 mRNA decreased until d 14 but returned to an intermediate level at d 35. Our results indicate that cPepT1 mRNA is regulated by both dietary protein and developmental stage. To investigate the kinetics of an ovine peptide transporter (oPepT1), CHO cells were transfected with oPepT1 cDNA. Uptake of Gly-Sar by transfected cells was pH-dependent, concentration-dependent, and saturable. Competition studies showed that all di-, tri-, and tetra-peptides inhibited uptake of Gly-Sar. Pretreatment of the cells with staurosporine resulted in an increase in peptide transport. This increase was blocked by pretreatment with PMA. The results indicate that protein kinase plays a role in oPepT1 function.

As image processing techniques become more and more applicable, major changes are taking place: image processing algorithms become more complicated and powerful machines with faster CPU and larger memory size are required to handle them; the number and variety of image processing algorithms become larger and larger, and are updated and modified by developers more frequently; the amount of image data used for processing become larger and larger that it is impossible to store them in a normal PC or workstation. All the above trends along with the boom of the Internet usage make it desirable to design a distributed image processing application system such that we can provide image processing as a service to end users across the Internet. The object of this thesis is to design and implement a flexible, convenient and scalable Web-based distributed image processing application system, through which, users can use the latest, complicated image processing service without much installation and configuration tasks, while algorithm developers can add new image processing methods and update existing ones in a convenient way. In this work, we focus on presenting basic concepts and ideas and introduce related technologies and issues that need special attention with respect to image processing and distributed application design. A simple implementation of the system prototype with illustrative examples and analysis are also provided to demonstrate the working of the system.

To study the mRNA found in sheep omasal epithelium encoding for a peptide transport protein(s), a 446-bp cDNA fragment was cloned from sheep omasal epithelium RNA. The predicted amino acid sequence of this fragment was 85.8, 90.5, and 90.5 percent identical to rabbit, human, and rat PepT1, respectively. The fragment was radiolabeled for use as a probe to study the distribution of the mRNA in various tissues. Total RNA was extracted and mRNA was isolated from the epithelium of gastrointestinal segments and other tissues as indicated. Northern blot analysis was conducted using the radiolabeled probe. In sheep (5) and lactating Holstein cows (3), hybridization was observed with mRNA from the omasum, rumen, duodenum, jejunum, and ileum. The estimated size of mRNA was 2.8 kb. No hybridization was observed with mRNA from the abomasum, cecum, colon, liver, kidney, and semitendinosus and longissimus muscles of either species or the mammary gland of the dairy cows. In pigs (6), the probe hybridized with mRNA from the duodenum, jejunum, and ileum. There was no hybridization with mRNA from the stomach, large intestine, liver, kidney, and semitendinosus and longissimus muscles. Two bands, 3.5 and 2.9 kb were observed with northern blot analysis, indicating two RNA transcripts that may result from alternative mRNA processing. In both Leghorns (15) and broilers (20), the strongest hybridization was found in the duodenum while the jejunum and ileum showed faint bands. The size of mRNA in chickens was 1.9 kb. Other tissues, including the crop, proventriculus, gizzard, ceca, liver, kidney, and muscles showed no hybridization to the probe. In conclusion, mRNA for a peptide transport protein(s) is present in the small intestine of all animals examined and the omasal and ruminal epithelium of sheep and dairy cows. The size of the mRNA varied among species.

Excised peanut embryos were sterilized by treatment with 1% NaOCl tor 5 minutes, and placed in 250-ml flasks containing nutrients and expanded granular shale. Nutrients consisted of Hoagland's solution supplemented with 1% sucrose and 0.03 ppm gibberellic acid. Plants were grown for 4 weeks in flasks placed between tubes of fluorescent lights at room temperature. When the plants were 2 to 3 inches tall the flasks were inoculated in the root zone singly and in all combinations with Aspergillus flavus, Streptomyces griseus, and Trichoderma sp. All 3 organisms invaded the root tissue. When compared with uninoculated check plants, S. griseus individually caused no measurable damage, but in combination caused stunting and chlorosis. A flavus and Trichoderma sp. alone killed plants within 15 and 20 days, respectively, after inoculation; while in combination they killed plants within 15 days. Inoculations of plants with all 3 fungi in combination caused less damage.

This investigation is concerned is concerned with how a commercial herbicide, dimethyl 2, 3, 5, 6-tetrachloroterephthalate (DCPA) affects the growth, morphology, and physiology of foxtail millet (Setaria italica (L.) Beav.). The objectives were to examine the nature of morphological changes, to determine what physiological and chemical changes accompanied the morphological alterations and to obtain information about the mechanism by which DCPA is herbicidal.