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The 2 µm communication windows has established itself amongst other solutions to address the capacity crunch. The 2 µm window offers three benefits: predicted ultra low loss windows of hollow-core fibres, optical amplification gain windows of thulium doped amplifier and compatibility with the silicon photonics silicon-oninsulator platform. We demonstrate state of the art high-speed modulators based on a 220 nm siliconon-insulator platform operating at a wavelength of 1950 nm using the free carrier plasma dispersion effect in silicon. The Mach-Zehnder interferometer carrierdepletion modulator has a modulation efficiency (Vπ·Lπ) of 2.89 V·cm at 4 V reverse bias. The insertion loss is 5.25 dB. It operates at a data rate of 25 Gbit/s OOK with an extinction ratio of 6.25 dB. We have also demonstrated a streamlined dual drive PAM4 generation method, producing 25 Gbit/s PAM4 signal using the same device. A Michelson interferometer is demonstrated with a Vπ·Lπ of 1.36 V·cm. It has almost double the efficiency of an equivalent MZM. It reaches a data rate of 20 Gbit/s. A broadband MZM was developed and its performance has been characterized at both 1550 nm and 1950 nm wavelengths. At 1950 nm, the carrier-depletion modulator operates at a data rate of 20 Gbit/s with an extinction ratio of 5.8 dB and insertion loss of 13 dB. The modulation efficiency (Vπ·Lπ) is 2.68 V·cm at 4 V reverse bias. At 1550 nm, an open eye is obtained at 30 Gbit/s. The difference in bandwidth is caused by the bandwidth limit of the 2 µm measurement setup. This work is a proof of principle demonstration, significantly improving previously published results and filling the long pending gap for the 2 µm silicon modulators. It paves a route towards a fully silicon-based transceiver in the 2 µm window.

This thesis provides a normative exploration of abortion law in England and China from a feminist, ethical and comparative standpoint. It proceeds from the assumption that legal regulation of abortion should take account of the principle of respect for autonomy. While I accept that the value of embryos and putative fathers' interests should be accorded recognition, I argue that legally women's autonomy should be given priority in abortion decisions. Following my discussion of traditional ethical accounts of the concept of 'autonomy', I argue that women's exercise of autonomy over abortion decisions is essential to satisfy their basic needs for health and for control over their lives. I expand upon the traditional account of the principle of respect for autonomy by employing a broadly liberal feminist approach. I argue that this approach to empowering women in abortion decisions is more constructive because it not only requires law makers to protect women's decision-making from controlling influences, but also advocates law's commitment to a female-friendly environment where medical and state support are accessible. While the concept of 'autonomy' is close to liberalism, I also draw upon the radical, global and multi-cultural schools of feminist thought. Following my investigation of the English and Chinese regulatory models of abortion, I argue that the main reason for women's lack of control over their autonomously held abortion decisions is that these two models have produced the power imbalance in the two key relationships: one between women who need abortion and health professionals and the other between female citizens and the state. I also suggest that the differences between the English and Chinese politico-legal systems do not rule out the possibility that their law makers can learn from each other's regulatory experiences. Thus, this comparative study provides a basis for drawing up proposals for the reform of the two models.

Background The HIV epidemic among the older population is increasing. This study aims to identify challenges in expanding HIV testing, initiating antiretroviral therapy (ART), and retaining in care among people living with HIV (PLWH) aged 50 and older in Guangdong, China.MethodsIn the qualitative study for HIV testing, we conducted one-on-one in-depth interviews with 30 PLWH, and two focus group discussions with 12 care providers and 10 social workers. In the quantitative studies for initiation and retention, we used existing data of national cohorts derived from China’s national HIV and treatment system. Additional structural-level information of 63 ART clinics was collected via an online survey in the study for retention. ResultsThe qualitative study highlighted challenges in four layers: 1) PLWH’s individual-layer barriers included a lack of basic knowledge, fear of HIV infection, a lack of social support, HIV discrimination, ageism, and fear of disclosure; 2) Care provider-layer obstacles were provider-patient age and gender concordance, unawareness of HIV infection among older adults, and limited time with patients; 3) a lack of involving social workers in HIV care was identified; 4) Institutional-layer challenges comprised less emphasis on post-screening counseling, deficiency in confidentiality and privacy, and workforce shortage.In the quantitative studies, among all 5,759 PLWH, 71% initiated ART at the end of the study. The median time to the first initiation was 35 days. ART initiation was associated with age, gender, residency, education levels, transmission modes, and testing sources. After adjusting for demographic covariates, initiation was associated with immune factors at the time of diagnosis. Among all 2,587 PLWH who initiated ART, 60% retained at the end of the study. ART retention was associated with age, testing sources, time to initiation since diagnosis, and routine education and counseling services in ART clinics.ConclusionPLWH, care providers, social workers, and policymakers should devote joint efforts to address challenges in expanding HIV testing services. Associated demographic factors may help identify older PLWH at higher risks of missing initiation and retention. The test-to-immediate-treatment policy, timely CD4 testing after diagnosis, and routine counseling and education need to be persistently implemented in the care continuum.

This empirical study was designed to explore the identity work of children who were adopted from China by American parent(s). The purposes of this study were to investigate how these children construct their identities as intercountry adoptees in the US, and to describe the subtle interaction of home and school cultures regarding these children’s identity formation. The identity of recent international adoptees is an under studied area, particularly these Chinese adoptees. The researcher followed 13 families who were affiliated with the Families with Children from China (FCC) in the Midwest over the course of 16 months in 2003 and 2004. The adult participants were between 36 and 59 years old; most of them were European Americans. The child participants were between 11 months and 13 years old, including biological and adoptive children in the families. Their post adoption experiences, family life, schooling, community, and FCC activities were studied to understand many of the core adoption issues in cultural identity; abandonment, schooling, racism, gender role, and community connections. The findings provided an understanding of the contextual reality these children lived. Children’s identity was multifaceted and fluid. Children in this study demonstrated great resilience and agency (Holland, 1998) as they actively negotiated their identities at home, at school, in FCC and their immediate communities. The researcher suggested the importance of public rituals to facilitate children’s Chinese identity development. In addition, the study also provided some up to date and useful information and understandings of Chinese adoptees identity formation for the concerned families, schools, and adoption professionals in international adoption communities.