Mechanisms of Vietnam's multidirectional foreign policy

It has been nearly 30 years since Vietnam shifted to a multidirectional foreign policy that places greater emphasis on cultivating friends and engaging with the international community. Vietnam has moved from being an isolated country, largely dependent on Soviet aid, to a country that bolsters its standing in bilateral and multilateral forums whilst reaping the economic benefits of greater integration into the global economy. Since the start of the 21st century, China’s more assertive posture, along with an increasingly complex, interdependent and multipolar world, has provided Vietnam with a host of problems. This article formulates a definition for a multidirectional foreign policy using Vietnam as a case study and argues that multidirectionalism allows Vietnam to reap economic benefits whilst safeguarding against uncertainty. Furthermore, the article tracks the three principal mechanisms through which Vietnam implements its multidirectional foreign policy: strategic and comprehensive partnerships, trade agreements, and multilateralism

Effects of Virtual Reality During Rowing Ergometry on Metabolic and Performance Parameters

Physical activity and moderate or intense exercise improve musculoskeletal and metabolic health; however, approximately 80% of Americans do not meet the minimum exercise recommendations from the American College of Sports Medicine (ACSM) or the Centers for Disease Control (CDC). Exercise intensity may be the most important factor in eliciting positive physical outcomes with exercise. PURPOSE: To assess the effectiveness of a proprietary virtual reality (VR) interface to increase metabolic and physical performance during rowing ergometry. METHODS: A novel VR software program for rowing ergometry was developed. Subsequently, sixteen apparently healthy, recreationally active individuals (12M, 4F; 35.5 ± 13.9 y; 174.5 ± 10.1 cm; 80.4 ± 12.8 kg; VO2max: 38.1 ± 5.6 mL/kg/min) were familiarized with the rowing ergometer and VR software, and then completed a VO2max test during two separate sessions. Finally, subjects performed four, 30-min rowing sessions in a randomized, counterbalanced order at maximal voluntary intensity in four different conditions: 1) no augmented visual or audio stimuli (CON), 2) no augmented visual stimuli with self-selected music (MUS), 3) screen-based environmental display (SB), and 4) a virtual reality environment (VR). Oxygen consumption, ventilation, heart rate, and the respiratory exchange ratio (RER) were measured continuously during the four experimental sessions; these data were then averaged over each 30-min testing period. Power output (W) and distance rowed (m) were measured and similarly reduced. Data (mean ± SD) were analyzed by repeated measures ANOVA and appropriate Tukey’s post hoc tests. Alpha was set at P \u3c 0.05. RESULTS: Oxygen consumption (CON: 2.23 ± 0.63 L/min; MUS: 2.30 ± 0.63 L/min; SB: 2.23 ± 0.71 L/min; VR: 2.19 ± 0.69 L/min), ventilation (CON: 74.2 ± 21.0 L/min; MUS: 77.5 ± 20.5 L/min; SB: 73.4 ± 23.9 L/min; VR: 71.7 ± 23.8 L/min), heart rate (CON: 154 ± 16 bpm; MUS: 156 ± 17 bpm; SB: 152 ± 23 bpm; VR: 154 ± 17 bpm), and RER (CON: 0.94 ± 0.04; MUS: 0.95 ± 0.04; SB: 0.94 ± 0.04; VR: 0.93 ± 0.05) were not different between conditions (all P \u3e 0.05). Performance outcomes also did not differ between conditions (CON: 126 ± 40 W, 6337 ± 763 m; MUS: 130 ± 42 W, 6486 ± 617 m; SB: 128 ± 46 W, 6358 ± 862 m; VR: 124 W ± 44 W, 6294 ± 849 m; all P \u3e 0.05). CONCLUSION: The pilot version of the VR software for rowing ergometry did not increase voluntary effort as determined by metabolic or physical performance outputs. Added features, such as greater immersion for reluctant exercisers, and competitive elements for highly motivated individuals, may elicit greater voluntary exertion with VR in rowing ergometry. Moreover, such applications may be more beneficial and improve exercise enjoyment in less experienced exercises who are not accustomed to high exercise intensities

Effects of Virtual Reality During Rowing Ergometry on Presence, Perceived Exertion, and Exercise Enjoyment

Physical inactivity is associated with a host of negative health outcomes. Approximately 80% of Americans do not meet minimum levels of recommended physical activity. Virtual reality (VR) may improve exercise outcomes by enhancing presence, decreasing perceived exertion, and increasing exercise enjoyment. PURPOSE: To assess the effects of a proprietary VR interface on presence, perceived exertion, and exercise enjoyment during rowing ergometry. METHODS: First, we developed a novel VR software program for rowing ergometry. Subsequently, sixteen apparently healthy, recreationally active individuals (12M, 4F; 35.5 ± 13.9 y; 174.5 ± 10.1 cm; 80.4 ± 12.8 kg; VO2max: 38.1 ± 5.6 mL/kg/min) were familiarized with the rowing ergometer and VR software, and then completed a VO2max test during two separate sessions. Finally, subjects performed four, 30-min rowing sessions in a randomized, counterbalanced order at maximal voluntary intensity in four different conditions: 1) no augmented visual or audio stimuli (CON), 2) no augmented visual stimuli with self-selected music (MUS), 3) screen-based environmental display (SB), and 4) a virtual reality environment (VR). Presence (Spatial Presence Experience Scale), perceived exertion (Borg 6-20 scale), and enjoyment (Exercise-Induced Feelings Inventory) were assessed using questionnaires. Data (mean ± SD) were analyzed by repeated measures ANOVA and appropriate Tukey’s post hoc tests. Alpha was set at P \u3c 0.05. RESULTS: Eight of twenty spatial presence items indicated an enhanced experience in VR vs. SB (P \u3c 0.05). Perceived exertion (CON: 14.7 ± 2.1; MUS: 14.9 ± 2.0; SB: 15.2 ± 2.5; VR: 14.9 ± 1.7) and exercise-induced feelings were not different between conditions (P \u3e 0.05). CONCLUSION: The pilot version of the VR software for rowing ergometry did not reduce perceived exertion or increase exercise enjoyment in recreationally active individuals, although it did facilitate improved user presence compared to a screen-based enhanced environment. Added features, such as better coupling of rowing intensity to boat velocity in VR may further enhance presence and immersion, thereby decreasing perceived exertion and increasing exercise enjoyment

Novel APC promoter and exon 1B deletion and allelic silencing in three mutation-negative classic familial adenomatous polyposis families

BACKGROUND: The overwhelming majority (approximately 80%) of individuals with classic familial adenomatous polyposis (FAP) exhibit mutations in the coding sequence of the adenomatous polyposis coli (APC) tumor suppressor gene. Families without detectable APC mutations are unable to benefit from the use of genetic testing for clinical management of this autosomal dominant syndrome. METHODS: We used exome sequencing and linkage analysis, coupled with second-generation sequencing of the APC locus including non-coding regions to investigate three APC mutation-negative classical FAP families. RESULTS: We identified a novel ~11 kb deletion localized 44 kb upstream of the transcription start site of APC that encompasses the APC 1B promoter and exon. This deletion was present only in affected family members of one kindred with classical FAP. Furthermore, this same deletion with identical breakpoints was found in the probands of two additional APC mutation-negative classical FAP kindreds. Phasing analysis of single nucleotide polymorphisms (SNPs) around the deletion site in the three probands showed evidence of a shared haplotype, suggesting a common founder deletion in the three kindreds. SNP analysis within the coding sequence of APC, revealed that this ~11 kb deletion was accompanied by silencing of one of the APC alleles in blood-derived RNA of affected individuals. CONCLUSIONS: These results support the causal role of a novel promoter deletion in FAP and suggest that non-coding deletions, identifiable using second-generation sequencing methods, may account for a significant fraction of APC mutation-negative classical FAP families

The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds. VIII. Serpens Observed with MIPS

We present maps of 1.5 deg^2 of the Serpens dark cloud at 24, 70, and 160 μm observed with the Spitzer Space Telescope MIPS camera. We describe the observations and briefly discuss the data processing carried out by the c2d team on these data. More than 2400 compact sources have been extracted at 24 μm, nearly 100 at 70 μm, and four at 160 μm. We estimate completeness limits for our 24 μm survey from Monte Carlo tests with artificial sources inserted into the Spitzer maps. We compare source counts, colors, and magnitudes in the Serpens cloud to two reference data sets: a 0.50 deg^2 set on a low-extinction region near the dark cloud, and a 5.3 deg^2 subset of the SWIRE ELAIS N1 data that was processed through our pipeline. These results show that there is an easily identifiable population of young stellar object candidates in the Serpens cloud that is not present in either of the reference data sets. We also show a comparison of visual extinction and cool dust emission illustrating a close correlation between the two and find that the most embedded YSO candidates are located in the areas of highest visual extinction

A North Atlantic tephrostratigraphical framework for 130-60 ka b2k:new tephra discoveries, marine-based correlations, and future challenges

Building chronological frameworks for proxy sequences spanning 130–60 ka b2k is plagued by difficulties and uncertainties. Recent developments in the North Atlantic region, however, affirm the potential offered by tephrochronology and specifically the search for cryptotephra. Here we review the potential offered by tephrostratigraphy for sequences spanning 130–60 ka b2k. We combine newly identified cryptotephra deposits from the NGRIP ice-core and a marine core from the Iceland Basin with previously published data from the ice and marine realms to construct the first tephrostratigraphical framework for this time-interval. Forty-three tephra or cryptotephra deposits are incorporated into this framework; twenty three tephra deposits are found in the Greenland ice-cores, including nine new NGRIP tephras, and twenty separate deposits are preserved in various North Atlantic marine sequences. Major, minor and trace element results are presented for the new NGRIP horizons together with age estimates based on their position within the ice-core record. Basaltic tephras of Icelandic origin dominate the framework with only eight tephras of rhyolitic composition found. New results from marine core MD99-2253 also illustrate some of the complexities and challenges of assessing the depositional integrity of marine cryptotephra deposits. Tephra-based correlations in the marine environment provide independent tie-points for this time-interval and highlight the potential of widening the application of tephrochronology. Further investigations, however, are required, that combine robust geochemical fingerprinting and a rigorous assessment of tephra depositional processes, in order to trace coeval events between the two depositional realms

The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds. VII. Ophiuchus Observed with MIPS

We present maps of 14.4 deg^2 of the Ophiuchus dark clouds observed by the Spitzer Space Telescope Multiband Imaging Photometer for Spitzer (MIPS). These high-quality maps depict both numerous point sources and extended dust emission within the star-forming and non–star-forming portions of these clouds. Using PSF-fitting photometry, we detect 5779 sources at 24 μm and 81 sources at 70 μm at the 10 σ level of significance. Three hundred twenty-three candidate young stellar objects (YSOs) were identified according to their positions on the MIPS/2MASS K versus color-magnitude diagrams, as compared to 24 μm detections in the SWIRE extragalactic survey. We find that more than half of the YSO candidates, and almost all those with protostellar Class I spectral energy distributions, are confined to the known cluster and aggregates

The Spitzer c2d Survey of Weak-line T Tauri Stars II: New Constraints on the Timescale for Planet Building

One of the central goals of the Spitzer Legacy Project ``From Molecular Cores to Planet-forming Disks'' (c2d) is to determine the frequency of remnant circumstellar disks around weak-line T Tauri stars (wTTs) and to study the properties and evolutionary status of these disks. Here we present a census of disks for a sample of over 230 spectroscopically identified wTTs located in the c2d IRAC (3.6, 4.5, 4.8, and 8.0 um) and MIPS (24 um) maps of the Ophiuchus, Lupus, and Perseus Molecular Clouds. We find that ~20% of the wTTs in a magnitude limited subsample have noticeable IR-excesses at IRAC wavelengths indicating the presence of a circumstellar disk. The disk frequencies we find in these 3 regions are ~3-6 times larger than that recently found for a sample of 83 relatively isolated wTTs located, for the most part, outside the highest extinction regions covered by the c2d IRAC and MIPS maps. The disk fractions we find are more consistent with those obtained in recent Spitzer studies of wTTs in young clusters such as IC 348 and Tr 37. From their location in the H-R diagram, we find that, in our sample, the wTTs with excesses are among the younger part of the age distribution. Still, up to ~50% of the apparently youngest stars in the sample show no evidence of IR excess, suggesting that the circumstellar disks of a sizable fraction of pre-main-sequence stars dissipate in a timescale of ~1 Myr. We also find that none of the stars in our sample apparently older than ~10 Myrs have detectable circumstellar disks at wavelengths < 24 um. Also, we find that the wTTs disks in our sample exhibit a wide range of properties (SED morphology, inner radius, L_DISK/L*, etc) which bridge the gaps observed between the cTTs and the debris disk regimes.Comment: 54 pages, 13 figures, Accepted by Ap

The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds. IV. Lupus Observed with MIPS

We present maps of 7.78 square degrees of the Lupus molecular cloud complex at 24, 70, and $160\:\mu$m. They were made with the Spitzer Space Telescope's Multiband Imaging Photometer for Spitzer (MIPS) instrument as part of the Spitzer Legacy Program, ``From Molecular Cores to Planet-Forming Disks'' (c2d). The maps cover three separate regions in Lupus, denoted I, III, and IV. We discuss the c2d pipeline and how our data processing differs from it. We compare source counts in the three regions with two other data sets and predicted star counts from the Wainscoat model. This comparison shows the contribution from background galaxies in Lupus I. We also create two color magnitude diagrams using the 2MASS and MIPS data. From these results, we can identify background galaxies and distinguish them from probable young stellar objects. The sources in our catalogs are classified based on their spectral energy distribution (SED) from 2MASS and Spitzer wavelengths to create a sample of young stellar object candidates. From 2MASS data, we create extinction maps for each region and note a strong corresponence between the extinction and the $160\:\mu$m emission. The masses we derived in each Lupus cloud from our extinction maps are compared to masses estimated from $^{13}$CO and C$^{18}$O and found to be similar to our extinction masses in some regions, but significantly different in others. Finally, based on our color-magnitude diagrams, we selected 12 of our reddest candidate young stellar objects for individual discussion. Five of the 12 appear to be newly-discovered YSOs.Comment: 15 pages, 17 figures, uses emulateapj.cls. Accepted for publication in ApJ. A version with high-quality figures can be found at http://peggysue.as.utexas.edu/SIRTF