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As China’s actions have become increasingly aggressive in the Indo-Pacific, the Quadrilateral Security Dialogue’s (Quad) growing interconnectedness reveals the West’s desire to preserve the liberal order. The Quad-- composed of the United States, Australia, India, and Japan-- was revived in 2017 amidst China’s encroachment on the sovereignty of Indo-Pacific nations and international waters. Through increased activity in infrastructure development, military interoperability, and key resource networks, the Quad’s renewal marks an acceleration of Western efforts to counter China’s growing threats to Western hegemony. By distilling the Quad’s activity into these three areas of cooperation, this paper examines the grouping’s actions and their implications for Western-China relations. In the area of infrastructure development, the Quad has emphasized a diversification of funding and high-quality practices to reduce reliance on China’s Belt and Road Initiative (BRI), and has promoted democratic priorities through the formation of the Blue Dot Network (BDN). Within military interoperability, the expansion of Exercise Malabar to include all Quad nations and the decision to host the exercise in the Bay of Bengal reveals the Quad’s increased challenge to China’s encroachment on Indo-Pacific oceans. The Quad’s desire to reduce Indo-Pacific nations’ reliance on China is evident in its efforts to exert influence over key resource networks such as undersea communication cables, Covid-19 vaccines, and global supply chains. The Quad’s increased activity within these three sectors represents the grouping’s elevation to an increasingly concrete alliance, emerging as one of the West’s primary measures to counter China’s growing influence in the Indo-Pacific and beyond.

The Taupō Volcanic Zone (TVZ) is characterised by a negative residual gravity anomaly that correlates with a zone of normal faulting, subsidence and voluminous silicic volcanism from c. 2 Ma. A ste...

A next-generation instrument named, Slicer Combined with Array of Lenslets for Exoplanet Spectroscopy (SCALES), is being planned for the W. M. Keck Observatory. SCALES will have an integral field spectrograph (IFS) and a diffraction-limited imaging channel to discover and spectrally characterize the directly imaged exoplanets. Operating at thermal infrared wavelengths (1-5 micron, and a goal of 0.6-5 micron), the imaging channel of the SCALES is designed to cover a 12"x 12" field of view with low distortions and high throughput. Apart from expanding the mid-infrared science cases and providing a potential upgrade/alternative for the NIRC2, the H2RG detector of the imaging channel can take high-resolution images of the pupil to aid the alignment process.Further, the imaging camera would also assist in small field acquisition for the IFS arm. In this work, we present the optomechanical design of the imager and evaluate its capabilities and performances., Comment: 11 pages, 9 Figures, SPIE Astronomical Telescopes + Instrumentation, (#12188-65), 2022, Montreal, Canada

After the 1992-1995 Bosnian genocide, citizens of all ethnicities pleaded for peace, yearning for a new beginning. Attempting to establish a more unified country, the highly unstructured government scrambled to piece together the broken country, resulting in a system referred to as “one state, two entities, three constituent peoples.” This approach to state unification recognizes the tiered governmental structure with the existence of state and entity (quasi-state) governments, which represent the one state and two entities, respectively. These governments are disproportionately influenced by people belonging to the three dominant ethnic groups, the Bosniaks, Croats, and Serbs, who represent the three constituent peoples. Nearing thirty years after the end of the genocide, with few effective improvements made to Bosnia’s haphazardly-made governmental system, Bosnia has struggled to ensure long-lasting peace. Despite attempts to ameliorate interethnic relations through changes in the state and entity level governments, the structural makeup and consequent actions of these governments face Bosnian citizens with genocide-era tensions and unimpaired ethnopolitical enclaves that threaten the stability of the country.

The use of optical fibers in astronomical instrumentation offers high-multiplex and light-gathering flexibility. However, with most previous fiber spectrographs optimized for large fields of view on modest-aperture telescopes, the performance of fibers in the context of faint targets on large telescopes remains largely untested. In this paper, we evaluate aspects of fiber stability, especially as they apply in the context of precision sky subtraction of faint sources at modest spectral resolution (R ∼ 3000). After introducing a framework for describing potential systematic errors, we use publicly available data from existing instruments, including instrumentation used by the fourth-generation Sloan Digital Sky Survey’s MaNGA project (MaNGA: Mapping Nearby Galaxies at Apache Point Observatory) and the Very Large Telescope’s FLAMES: Fiber Large Array Multi Element Spectrograph. We isolate sources of fiber systematics and estimate the observed amplitude of persistent residuals as well as stochastic noise contributions resulting from changing fiber stresses. Comparing these levels against their impact on various sky subtraction schemes demonstrates that 0.1% precision sky subtraction with fiber instruments is possible. As a demonstration, we show that the MaNGA instrument can deliver 0.2% residuals on bright near-IR sky lines with nonlocal sky subtraction, if pseudo-slit limitations are addressed by allocating 50% of its fibers to sky. We further highlight recently published deep exposures that achieved a 1σ background level of 27.6 AB per square arc second, equivalent to a precision of 0.2% of the sky background continuum.

Since 1997 Hong Kong has operated as a Special Administrative Region (SAR) of the People’s Republic of China under a policy known as “One Country, Two Systems.” An analysis of the critical period of 1997-2020 (which came to a close with the 2020 National Security Law) demonstrates the ways in which the People’s Republic of China has used its influence to limit the democratic autonomy and ideological independence of the Hong Kong Special Administrative Region. By breaking down China’s actions into three distinct sections of politics, media, and education this review addresses the many layers and facets of Chinese encroachment on the freedoms of the people of Hong Kong. In the political sector, China has worked to limit democratic representation in Hong Kong via interference in the executive, legislative, and judicial branches of Hong Kong’s government. In the field of media, China has used direct and indirect editorial action as well as economic influence to limit negative perceptions of Beijing. In the education system, China has taken a top-down approach to instill Chinese patriotism in Hong Kong’s curriculum to expand the support for China in Hong Kong’s youth. Tracking these violations of Hong Kong’s autonomy and also the people’s response demonstrates that although China continues to push the “One Country” aspect of the “One Country, Two Systems” policy, the people of Hong Kong will continue to fight for their freedoms as long as they have a voice.

Summary Cellular cheating leading to cancers exists in all branches of multicellular life, favoring the evolution of adaptations to avoid or suppress malignant progression, and/or to alleviate its fitness consequences. Ecologists have until recently largely neglected the importance of cancer cells for animal ecology, presumably because they did not consider either the potential ecological or evolutionary consequences of anticancer adaptations. Here, we review the diverse ways in which the evolution of anticancer adaptations has significantly constrained several aspects of the evolutionary ecology of multicellular organisms at the cell, individual, population, species, and ecosystem levels and suggest some avenues for future research., Graphical Abstract, Biological Sciences; Evolutionary Biology; Evolutionary Ecology; Cancer Systems Biology

Inter-individual transmission of cancer cells represents an intriguing and unexplored host-pathogen system, with significant ecological and evolutionary ramifications. The pathogen consists of clonal malignant cell lines that spread horizontally as allografts and/or xenografts. Although only nine transmissible cancer lineages in eight host species from both terrestrial and marine environments have been investigated, they exhibit evolutionary dynamics that may provide novel insights into tumor-host interactions particularly in the formation of metastases. Here we present an overview of known transmissible cancers, discuss the necessary and sufficient conditions for cancer transmission, and provide a comprehensive review on the evolutionary dynamics between transmissible cancers and their hosts., Graphical Abstract, Biological Sciences; Evolutionary Biology; Evolutionary Ecology; Cancer

The Apache Point Observatory Galactic Evolution Experiment (APOGEE) will use a dedicated 300-fiber, narrow-band (1.5-1.7 micron), high resolution (R~30,000), near-infrared spectrograph to survey approximately 100,000 giant stars across the Milky Way. This survey, conducted as part of the Sloan Digital Sky Survey III (SDSS III), will revolutionize our understanding of kinematical and chemical enrichment histories of all Galactic stellar populations. The instrument, currently in fabrication, will be housed in a separate building adjacent to the 2.5 m SDSS telescope and fed light via approximately 45-meter fiber runs from the telescope. The instrument design includes numerous technological challenges and innovations including a gang connector that allows simultaneous connection of all fibers with a single plug to a telescope cartridge that positions the fibers on the sky, numerous places in the fiber train in which focal ratio degradation must be minimized, a large (290 mm x 475 mm elliptically-shaped recorded area) mosaic-VPH, an f/1.4 sixelement refractive camera featuring silicon and fused silica elements with diameters as large as 393 mm, three near-within a custom, LN2-cooled, stainless steel vacuum cryostat with dimensions 1.4 m x 2.3 m x 1.3 m.