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GaSb-based materials can be used to produce high performance photonic devices operating in the technologically important mid-infrared spectral range. Direct epitaxial growth of GaSb on silicon (Si) is an attractive method to reduce manufacturing costs and opens the possibility of new applications, such as lab-on-a-chip MIR photonic integrated circuits and monolithic integration of focal plane arrays (FPAs) with Si readout integrated circuits (ROICs). However, fundamental material dissimilarities, such as the large lattice mismatch, polar-nonpolar character of the III-V/Si interface and differences in thermal expansion coefficients lead to the formation of threading dislocations and antiphase domains, which effect the device performance. This work reports on the molecular beam epitaxial growth of high quality GaSb-based materials and devices onto Si. This was achieved using a novel growth procedure consisting of an efficient AlSb interfacial misfit array, a two-step GaSb growth temperature procedure and a series of dislocation filter superlattices, resulting in a low defect density, anti-phase domain free GaSb buffer layer on Si. A nBn barrier photodetector based on a type-II InAs/InAsSb superlattice was grown on top of the buffer layer. The device exhibited an extended 50 % cut-off wavelength at 5.40 μm at 200 K which moved to 5.9 μm at 300 K. A specific detectivity of 1.5 x1010 Jones was measured, corresponding in an external quantum efficiency of 25.6 % at 200 K.

Direct integration of III–V semiconductor light sources on silicon is an essential step toward the development of portable, on-chip infrared sensor systems. Driven by the presence of characteristic molecular fingerprints in the mid-infrared (MIR) spectral region, such systems may have a wide range of applications in infrared imaging, gas sensing, and medical diagnostics. This paper reports on the integration of an InAs virtual substrate and high crystalline quality InAs/InAsSb multi-quantum wells on Si using a three-stage InAs/GaSb/Si buffer layer. It is shown that the InAs/GaSb interface demonstrates a strong dislocation filtering effect. A series of strained AlSb/InAs dislocation filter superlattices was also used, resulting in a low surface dislocation density of approximately 4 × 107 cm−2. The InAs/InAsSb wells exhibited a strong photoluminescence signal at elevated temperatures. Analysis of these results indicates that radiative recombination is the dominant recombination mechanism, making this structure promising for fabricating MIR Si-based sensor systems.

Following the dismissal of Captain Richard Pratt from the position of superintendent in 1904, the Carlisle Indian School entered a new era. The school became more focused on vocational education and moved away from offering immediate civilisation to the students. The school even promoted Indian arts and crafts. This move was also reflected in sport at Carlisle. The school became determined to construct a successful athletic programme. This resulted in the rise of masculine gamesmanship among the athletes. This, combined with racial pride, formed the basis of the athletes' manhood in the post-Pratt era. Yet, despite the demonstration of superior masculinity through victories, the school still positioned the students as subordinate to white men. The players were portrayed as comparatively unintelligent; they were apparently incapable of actually coaching the team.

We present the results of an investigation into the growth of InGaSb/GaAs quantum dots (QDs) by molecular beam epitaxy using migration-enhanced epitaxy. Surface atomic force microscopy and cross-sectional transmission electron microscopy show that the QDs undergo a significant change in morphology upon capping with GaAs. A GaAs ‘cold capping’ technique was partly successful in preserving QD morphology during this process, but strong group V intermixing was still observed. Energy-dispersive x-ray spectroscopy reveals that the resulting nanostructures are small ‘core’ QDs surrounded by a highly intermixed disc. Temperature varying photoluminescence measurements indicate strong light emission from the QDs, with an emission wavelength of 1230 nm at room temperature. Nextnano 8x8 k.p calculations show good agreement with the PL results and indicate a low level of group-V intermixing in the core QD.

t the Carlisle Industrial Indian School in 1893, a group of forty male stu- dents defiantly approached Superintendent Captain Richard Henry Pratt's office. American football had been banned at the school the previous year after Stacy Matlock suffered a broken leg in a game against Dickinson College. According to his autobiography, Pratt had accompanied Matlock to the local hospital and helped set the leg. During the same period Paul Shattuck had broken his collarbone in a "fiendish football game." 1 Pratt's disgust towards the separate accidents resulted in the outlawing of games against other institutions. A year later, the students requested the reinstatement of football and engaged the school's champion orator to argue their position. Pratt listened silently and, convinced by the "genius" of the argument, eventually relented to the students' demand but set two conditions: First, that you will never, under any circumstances, slug. That you will play fair straight through, and if the other fellows slug you will in no case return it. Can't you see that if you slug, people who are looking on will say, "There, that's the Indian of it. Just see them. They are savages and you can't get it out of them" . . . My other condition is this. That, in the course of two, three, or four years you will develop your strength and ability to such a degree that you will whip the biggest football team in the country. 2 The students considered his conditions and agreed to both. The promise of fair play and victory over the best white colleges formed the foundation for the reintroduction and continuation of football at Carlisle. Pratt founded the Carlisle Indian Industrial School in 1879 with the aim of assimilating Native children through acculturation. The students' Native cul- tures were to be systematically dismantled and replaced with white standards and beliefs. This formed part of a three-pronged attack on the Native population.

This paper provides the rationale for a new education for sustainable development (ESD) project being developed in Australia.Titled Project otherWISE, it seeks to build the capacity of young Australians to be agents of change towards sustainable lifestyles in their communities. The rationale for the project is grounded in three themes that are analysed in this paper. The first is an explanation of consumption as a key defining characteristic of contemporary society and the social and environmental impacts of global consumerism. The second is the rise of postmaterial values and the potential of sustainable consumption to provide alternatives to mainstream lifestyles. The third is the enormous potential for young people to develop skills in questioning the pressures towards unthinking consumption and to create alternative ways of living in the world.

Salmonella enterica serovar Typhi strains with mutations in the Salmonella pathogenicity island-2 (SPI-2) may represent an effective strategy for human vaccine development, and a vectoring system for heterologous antigens. S. Typhi (Ty2 aroC-ssaV-) M01ZH09 is an attenuated, live, oral typhoid vaccine harboring defined deletion mutations in ssaV, which encodes an integral component in the SPI-2 type III secretion system (TTSS), as well as a mutation in an aromatic biosynthetic pathway needed for bacterial growth in vivo (aroC). SPI-2 mutant vaccines have yet to be evaluated in a large, randomized human trial. A simplified or single-oral dose oral typhoid vaccine using the SPI-2 strategy would offer significant advantages over the currently licensed typhoid vaccines. We performed a double-blinded, placebo-controlled, dose-escalating clinical trial in 60 healthy adult volunteers to determine the tolerability and immunogenicity of a single dose of M01ZH09. Three groups of 20 healthy adult volunteers were enrolled; 16 in each group received a single oral dose of the freeze-dried vaccine at 5 x 10(7), 5 x 10(8) or 5 x 10(9)CFU in a bicarbonate buffer. Four volunteers in each cohort received placebo in the same buffer. Adverse events were infrequent and not statistically different between vaccine and placebo recipients, although two subjects in the mid-range dose and three subjects in the highest dose had temperature measurements >37.5 degrees C. No blood or urine cultures were positive for M01ZH09, and fecal shedding was brief. The immune response was dose-related; the highest vaccine dose (5 x 10(9)CFU) was the most immunogenic. All tested subjects receiving the highest dose had a significant ASC response (mean 118 spots/10(6) cells). A >or=4-fold increase in antibody titer for S. Typhi LPS or flagellin was detected in 75% of volunteers in the highest-dose cohort by day 28. The SPI-2 mutant vaccine, M01ZH09, is a promising typhoid vaccine candidate and deserves further study as a vectoring system for heterologous vaccine antigens.

BACKGROUND M01ZH09 (Salmonella enterica serovar Typhi [Ty2 aroC(-) ssaV(-)] ZH9) is a live oral-dose typhoid vaccine candidate. M01ZH09 was rationally modified with 2 independently attenuating mutations, including a novel mutation in Salmonella pathogenicity island (SPI)-2. We demonstrate that M01ZH09, in a single oral dose, is well tolerated and prompts broad immune responses, regardless of whether prevaccination with a bicarbonate buffer is given. METHODS Thirty-two healthy adult subjects were randomized and given 5x109 cfu of M01ZH09, with (presentation 1) or without (presentation 2) prevaccination with a bicarbonate buffer. Immunogenicity data included Salmonella Typhi lipopolysaccharide (LPS)-specific immunoglobulin (Ig) A antibody-secreting cells (enzyme-linked immunospot [ELISPOT] assay), IgG serologic responses to Salmonella Typhi LPS, lymphocyte proliferation, and interferon (IFN)- gamma production. RESULTS The vaccine was well tolerated; adverse events after vaccination were mild. No fever or prolonged vaccine shedding occurred. Immunogenicity data demonstrated that 88% and 93% of subjects who received presentation 1 and presentation 2, respectively, had a positive response by ELISPOT assay; 81% of subjects in both groups underwent IgG seroconversion on day 14. Both groups had similar cellular immune responses to presentation 1 and presentation 2; lymphocyte proliferation to Salmonella Typhi flagellin occurred in 63% and 67% of subjects, respectively, and 69% and 73% of subjects, respectively, had an increase in IFN- gamma production. CONCLUSION The oral typhoid vaccine M01ZH09 is well tolerated and highly immunogenic in a single oral dose, with and without prevaccination with a bicarbonate buffer. Field studies to demonstrate protective efficacy are planned.

Novel candidate live oral vaccines based on aSalmonella entericaserovar Typhi ZH9 (Ty2 ΔaroCΔssaV) derivative that directed the expression of either the B subunit ofEscherichia coliheat-labile toxin or hepatitis B virus core antigen from the bacterial chromosome using the in vivo induciblessaGpromoter were constructed. The levels of attenuation of the twoS. entericaserovar Typhi ZH9 derivatives were similar to that of the parent as assessed by measuring the replication of bacteria within human macrophage-like U937 cells. The expression of heterologous antigen in the respectiveS. entericaserovar Typhi ZH9 derivatives was up-regulated significantly within U937 cells compared to similarS. entericaserovar Typhi ZH9 derivative bacteria grown in modified Luria-Bertani broth supplemented with aromatic amino acids. Immunization of mice with theseS. entericaserovar Typhi ZH9 derivatives stimulated potent antigen-specific serum immunoglobulin G responses to the heterologous antigens.

AIDS-related B-cell non-Hodgkin's lymphoma (AIDS-NHL) is a significant cause of morbidity and mortality among individuals infected with human immunodeficiency virus type 1 (HIV-1). AIDS-NHL is clinically and histologically heterogeneous, but common features include an aggressive clinical course and frequent extranodal presentation. HIV-1 infection of nonimmune cells that interact with malignant B cells at extranodal sites may influence both the development and the clinical presentation of disease. Our previous studies have shown that coculture of B-lymphoma (BL) cells with HIV-1-infected endothelial cells (EC) leads to contact activation of EC and firm BL-cell adhesion. The key event promoting EC-BL-cell adhesion was HIV-1 upregulation of endothelial CD40, which allowed induction of vascular cell adhesion molecule 1 (VCAM-1) in a CD40-dependent manner. The present study was designed to identify the HIV-1 protein(s) that influence EC-BL-cell adhesion. When HIV-1 proteins were individually expressed in EC by using recombinant adenoviruses, cultured BL cells adhered exclusively to Vpu-transduced EC. As with HIV-infected EC, adhesive properties were linked to the capacity of Vpu to upregulate CD40, which in turn allowed efficient expression of VCAM-1. When EC were infected with an HIV-1 pseudotype lacking the Vpu gene, CD40 upregulation and BL-cell adhesive properties were lost, indicating an essential role for Vpu in EC-BL-cell interactions. Thus, these data reveal a novel function for HIV-1 Vpu and further suggest a role for Vpu in the development of AIDS-NHL at EC-rich extranodal sites.

The attenuation and immunogenicity of two novel Salmonella vaccine strains, Salmonella enterica serovar Typhi (Ty2 Δ aroC Δ ssaV , designated ZH9) and S. enterica serovar Typhimurium (TML Δ aroC Δ ssaV , designated WT05), were evaluated after their oral administration to volunteers as single escalating doses of 10 7 , 10 8 , or 10 9 CFU. ZH9 was well tolerated, not detected in blood, nor persistently excreted in stool. Six of nine volunteers elicited anti-serovar Typhi lipopolysaccharide (LPS) immunoglobulin A (IgA) antibody-secreting cell (ASC) responses, with three of three vaccinees receiving 10 8 and two of three receiving 10 9 CFU which elicited high-titer LPS-specific serum IgG. WT05 was also well tolerated with no diarrhea, although the administration of 10 8 and 10 9 CFU resulted in shedding in stools for up to 23 days. Only volunteers immunized with 10 9 CFU of WT05 mounted detectable serovar Typhimurium LPS-specific ASC responses and serum antibody responses were variable. These data indicate that mutations in type III secretion systems may provide a route to the development of live vaccines in humans and highlight significant differences in the potential use of serovars Typhimurium and Typhi.

The incidence of non-responders to hepatitis B (HB) virus SHBs antigen (Ag) vaccines has prompted the development of pre-S containing vaccines. The aim of this study was to characterise the murine immune response to a novel recombinant particle (Hepagene™) (Medeva plc) containing pre-S1, pre-S2 and SHBsAg components. Hepagene™ induced potent in vitro spleen T-cell proliferative responses in both BALB/c (maximum stimulation index (SI)=38) and SWR/J (maximum SI=43) strains of mouse, following immunisation. High concentrations of interferon-γ and low concentrations of interleukin-10 were detected in the media of spleen cells stimulated with Hepagene™. The anti-Hepagene™ antibody response was higher in SWR/J mice and alhydrogel adjuvant significantly improved the titres. Anti-pre-S1 antibody was detected in both strains of mouse, whereas anti-pre-S2 antibody was only detected in SWR/J mice. IgG subclass analysis of the anti-Hepagene™ response revealed a Th2-type response in BALB/c mice and a mixed Th1/Th2 response in SWR/J mice. Hepagene™ induced higher anti-SHBs antibody responses than Engerix-B® (11097 and 1276 IU/ml, respectively) in BALB/c mice. Hepagene™ therefore, stimulates strong cellular and humoral immune responses in murine models. The high anti-SHBs antibody response suggests that Hepagene™ is an improved hepatitis B virus vaccine.

The attenuation and immunogenicity of two novel Salmonella vaccine strains, Salmonella enterica serovar Typhi (Ty2 Delta aroC Delta ssaV, designated ZH9) and S. enterica serovar Typhimurium (TML Delta aroC Delta ssaV, designated WT05), were evaluated after their oral administration to volunteers as single escalating doses of 10(7), 10(8), or 10(9) CFU. ZH9 was well tolerated, not detected in blood, nor persistently excreted in stool. Six of nine volunteers elicited anti-serovar Typhi lipopolysaccharide (LPS) immunoglobulin A (IgA) antibody-secreting cell (ASC) responses, with three of three vaccinees receiving 10(8) and two of three receiving 10(9) CFU which elicited high-titer LPS-specific serum IgG. WT05 was also well tolerated with no diarrhea, although the administration of 10(8) and 10(9) CFU resulted in shedding in stools for up to 23 days. Only volunteers immunized with 10(9) CFU of WT05 mounted detectable serovar Typhimurium LPS-specific ASC responses and serum antibody responses were variable. These data indicate that mutations in type III secretion systems may provide a route to the development of live vaccines in humans and highlight significant differences in the potential use of serovars Typhimurium and Typhi.