CSLP in Sham Shui Po (理有「深」社區服務計劃) : a district-based service learning project, its mode of delivery and effectiveness

Background: The Hong Kong Polytechnic University (PolyU) is committed to producing all-round graduates who are also responsible citizens and contributive members of the society. The annual campus-wide Community Service Learning Programme (CSLP) has been organized since 2004 to encourage staff and students to serve the community through the use of their professional knowledge and skills. About 800 students work on various service projects each year to serve the underprivileged groups of Hong Kong, Chinese mainland and overseas. In 2010/11, we started a new mode of service delivery with the implementation of a District-based Service-Learning Project in a relatively deprived area in HK, Sham Shui Po. We aim to organise more sustainable services by focusing the manpower and resources in serving the people in a particular district so that we can create bigger impacts and bring more benefits to the community. The Programme: Through collaboration with the Sham Shui Po District Social Welfare Office, we have successfully invited over 30 local NGOs and schools as our project partners. Together, 60 service projects of different nature and scales were planned and carried out during 2010-2012. The programme has generated a lot of synergy amongst students from different disciplines e.g. students from design schools working together with students from building services in improving the home environment of the lower income families; students from nursing school work together with social work and science students in promoting holistic health care for the elderly etc. Overall, the project has allowed us to provide more integrated services to the community people in various aspects including health care, education, improvement of the living environment and social integration. Effectiveness: The District-based Project has proven to be an effective mode of service delivery. By focusing our manpower and resources in a single district, we were more able to identify the community needs, organise larger scale and sustainable projects, and provide more integrated services to create a bigger impact to the community. During 2010-12, over 500 students from various disciplines had participated in 60 service projects and committed over 3100 service hours in total. The whole project has served more than 4,000 people in the district, addressing the needs of different target groups such as the elderly, new immigrants, lower income families, school children and the disabled

KIR2DL2/2DL3-E(35) alleles are functionally stronger than -Q(35) alleles.

KIR2DL2 and KIR2DL3 segregate as alleles of a single locus in the centromeric motif of the killer cell immunoglobulin-like receptor (KIR) gene family. Although KIR2DL2/L3 polymorphism is known to be associated with many human diseases and is an important factor for donor selection in allogeneic hematopoietic stem cell transplantation, the molecular determinant of functional diversity among various alleles is unclear. In this study we found that KIR2DL2/L3 with glutamic acid at position 35 (E(35)) are functionally stronger than those with glutamine at the same position (Q(35)). Cytotoxicity assay showed that NK cells from HLA-C1 positive donors with KIR2DL2/L3-E(35) could kill more target cells lacking their ligands than NK cells with the weaker -Q(35) alleles, indicating better licensing of KIR2DL2/L3(+) NK cells with the stronger alleles. Molecular modeling analysis reveals that the glutamic acid, which is negatively charged, interacts with positively charged histidine located at position 55, thereby stabilizing KIR2DL2/L3 dimer and reducing entropy loss when KIR2DL2/3 binds to HLA-C ligand. The results of this study will be important for future studies of KIR2DL2/L3-associated diseases as well as for donor selection in allogeneic stem cell transplantation

Spontaneous spin ordering of Dirac spin liquid in a magnetic field

The Dirac spin liquid was proposed to be the ground state of the spin-1/2 Kagome antiferromagnets. In a magnetic field $B$, we show that the state with Fermi pocket is unstable to the Landau level (LL) state. The LL state breaks the spin rotation around the axis of the magnetic field. We find that the LL state has an in-plane 120$^{\circ}$ $q=0$ magnetization $M$ which scales with the external field $M\sim B^{\alpha}$, where $\alpha$ is an intrinsic calculable universal number of the Dirac spin liquid. We discuss the related experimental implications which can be used to detect the possible Dirac spin liquid phase in Herbertsmithite ZnCu$_3$(OH)$_6$Cl$_2$.Comment: rewritten for clarit

Those Wonderful People across the Sea: Positive Out-Group Bias by Caucasians toward Asians

While individuals often favor their in-group, they sometimes favor an out-group, such as when Caucasians positively stereotype Asians\u27 quantitative abilities. It is unclear, however, whether positive stereotypes of Asians extend into other domains and create a generalized halo effect that influences judgments on other attributes. To examine this, three studies were performed. In Study 1, Asians and Caucasians were equally biased toward an Asian\u27s response to a calculus problem. In Study 2, Asians, but not Caucasians, gave lower grades to essay writers they guessed were Asian. In Study 3, Caucasians rated their ethnic group with fewer positive terms and more negative terms than they rated Asians on general personality characteristics. Results suggest that Caucasians\u27 views of Asians are more positive than self-judgments of each group, and that Caucasians’ judgments about Asians may be influenced by a generalized halo effect

Endocytosis of PEGylated nanoparticles accompanied by structural and free energy changes of the grafted polyethylene glycol

AbstractNanoparticles (NPs) are in use to efficiently deliver drug molecules into diseased cells. The surfaces of NPs are usually grafted with polyethylene glycol (PEG) polymers, during so-called PEGylation, to improve water solubility, avoid aggregation, and prevent opsonization during blood circulation. The interplay between grafting density σp and grafted PEG polymerization degree N makes cellular uptake of PEGylated NPs distinct from that of bare NPs. To understand the role played by grafted PEG polymers, we study the endocytosis of 8 nm sized PEGylated NPs with different σp and N through large scale dissipative particle dynamics (DPD) simulations. The free energy change Fpolymer of grafted PEG polymers, before and after endocytosis, is identified to have an effect which is comparable to, or even larger than, the bending energy of the membrane during endocytosis. Based on self-consistent field theory Fpolymer is found to be dependent on both σp and N. By incorporating Fpolymer, the critical ligand-receptor binding strength for PEGylated NPs to be internalized can be correctly predicted by a simple analytical equation. Without considering Fpolymer, it turns out impossible to predict whether the PEGylated NPs will be delivered into the diseased cells. These simulation results and theoretical analysis not only provide new insights into the endocytosis process of PEGylated NPs, but also shed light on the underlying physical mechanisms, which can be utilized for designing efficient PEGylated NP-based therapeutic carriers with improved cellular targeting and uptake

How do the better educated earn more? : evidence from rural China

DraftThis study seeks a better understanding on how education is rewarded. Drawing on the recent experiences of reforms in rural China, I estimate household net profit function using China Household Income Project (CHIP) for 2002. I find strong support that education influences household net profits through two channels: (1) education improves allocation of factor inputs and hence increases net profits; (2) education directly increases profits. It is estimated that an additional year of education is associated with 2.5 percent increase in net profits: 1.1 percent comes from more efficient allocation of labor; 0.35 percent comes from better utilization of capital investment; 1.09 percent comes directly from increasing profits. The study has potentially important policy implications for completing China’s market reforms. It also sheds light on how schooling should be financed, particularly focusing on a few rather than universal provision of schooling may have direct impact on income