Impact of foreign investment on household welfare: Evidence from Vietnam

Available online 27 July 2019We examine the impact of foreign direct investment in Vietnam on household and individual welfare and on migration using survey data for the period 2002 to 2016. We find that higher revenue from foreign invested firms measured at province level and normalized on population is associated with a variety of positive outcomes. At household level, income and expenditures per capita are higher and poverty incidence is lower. At individual level, non-farm employment and wages are higher. And at commune level, in-migration is higher. However, although these improvements register as statistically signficant, the magnitudes in economic terms are modest.Anh Tuan Bui, Cuong Viet Nguyen, Thu Phuong Pha

Molecular epidemiology of white spot syndrome virus within Vietnam

White spot syndrome virus (WSSV), the sole member of the virus family Nimaviridae, is a large double-stranded DNA virus that infects shrimp and other crustaceans. By alignment of three completely sequenced isolates originating from Taiwan (WSSV-TW), China (WSSV-CN) and Thailand (WSSV-TH), the variable loci in the genome were mapped. The variation suggests the spread of WSSV from a common ancestor originating from either side of the Taiwan Strait to Thailand, but support for this hypothesis through analysis of geographical intermediates is sought. RFLP analysis of eight Vietnamese WSSV isolates, of which six were collected along the central coast (VN-central) and two along the south coast (VN-south), showed apparent sequence variation in the variable loci identified previously. These loci were characterized in detail by PCR amplification, cloning and sequencing. Relative to WSSV-TW, all VN-central isolates showed a similar to8.5 kb deletion in the major variable region ORF23/24, whereas the VN-south isolates contain a deletion of similar to11(.)5 or similar to12(.)2 kb, compared to a similar to1(.)2 or similar to13(.)2 kb deletion in WSSV-CN and WSSV-TH, respectively. The minor variable region ORF14/15 showed deletions of various sizes compared with WSSV-TH for all eight VN isolates. The data suggest that the VN isolates and WSSV-TH have a common lineage, which branched off from WSSV-TW and WSSV-CN early on, and that WSSV entered Vietnam by multiple introductions. A model is presented for the spread of WSSV from either side of the Taiwan Strait into Vietnam based on the gradually increasing deletions of both 'variable regions'. The number and order of repeat units within ORF75 and ORF125 appeared to be suitable markers to study regional spread of WSSV

The management of diabetic ketoacidosis in children

The object of this review is to provide the definitions, frequency, risk factors, pathophysiology, diagnostic considerations, and management recommendations for diabetic ketoacidosis (DKA) in children and adolescents, and to convey current knowledge of the causes of permanent disability or mortality from complications of DKA or its management, particularly the most common complication, cerebral edema (CE). DKA frequency at the time of diagnosis of pediatric diabetes is 10%–70%, varying with the availability of healthcare and the incidence of type 1 diabetes (T1D) in the community. Recurrent DKA rates are also dependent on medical services and socioeconomic circumstances. Management should be in centers with experience and where vital signs, neurologic status, and biochemistry can be monitored with sufficient frequency to prevent complications or, in the case of CE, to intervene rapidly with mannitol or hypertonic saline infusion. Fluid infusion should precede insulin administration (0.1 U/kg/h) by 1–2 hours; an initial bolus of 10–20 mL/kg 0.9% saline is followed by 0.45% saline calculated to supply maintenance and replace 5%–10% dehydration. Potassium (K) must be replaced early and sufficiently. Bicarbonate administration is contraindicated. The prevention of DKA at onset of diabetes requires an informed community and high index of suspicion; prevention of recurrent DKA, which is almost always due to insulin omission, necessitates a committed team effort

Female leadership and borrowing constraints: Evidence from an emerging economy

Available online 24 March 2019This study investigates the differences in credit access between male-managed and female-managed firms using two Enterprise Censuses in Vietnam. Our findings reveal that women-managed firms are less likely to borrow from commercial banks than their male counterparts, even when controlling for other determinants such as CEO education and experience, firm size, and ownership. No difference in credit access is documented for firms borrowing from non-commercial banks. Once we control for firm characteristics and CEO demographic factors, approved loan size is higher for firms managed by female CEOs regardless of the borrowing source. Using decomposition analysis, we find firm size contributes most in explaining the difference in credit access between female and male-managed companies.Anh Tuan Bui, Cuong Viet Nguyen, Thu Phuong Pham, Duc Tung Phun

Multi-color fluorescence of pNIPAM-Based nanogels modulated by dual stimuli-responsive FRET processes

We report the modulation of the dual photo/thermo-responsive multicolor fluorescence from poly(N-isopropyl acrylate) pNIPAM-based nanogels. The thermo-responsive pNIPAM-crosslinked matrix was covalently copolymerized with nitrobenzoxadiazole (NBD) monomers as a Förster resonance energy transfer (FRET) donor and electrostatically conjugated with photochromic spiropyran (SP) dyes as a FRET acceptor. The pristine nanogel emits green fluorescence derived from the NBD moieties; however, the irradiation of the nanogels with UV light led to the transformation of the ring-closed colorless SP moieties to the ring-opened coral-red merocyanine (MC) moieties, resulting in light-pink fluorescent nanogels. Notably, at higher temperatures, the fluorescence of the nanogels was red-shifted and enhanced by the more efficient FRET process. The nanogels were well-distributed in the cellular cytoplasm and showed excellent photochromic function in the subcellular environment for applications as photo-switchable bio-imaging agents and nanothermometers. © 2017 Elsevier L

Harvesting Ambient RF Energy Efficiently With Optimal Angular Coverage

International audienceAmbient electromagnetic and RF energy is an ubiquitous energy resource that is found everywhere but difficult to harvest because of the time-varying orientation of incoming radiations and the low efficiency of RF rectifiers resulting from a low input power density operation. In response to these two challenges that come with the design of rectennas for ambient energy harvesting, this paper discusses a Figure-of-Merit to evaluate the rectenna performance that combines the rectification efficiency, the radiation efficiency, and the spherical coverage of the antenna. To illustrate this proposed Figure-of-Merit, a rectenna with a strengthen RF-to-DC efficiency and also a full spatial coverage is designed using beam-forming networks. The resulting system is demonstrated for a wireless sensor mounted on a pole. To maintain a reasonable size of the prototype, a miniaturization technique of a 4x4 Butler matrix is investigated, which allows for the reduction of the footprint of the Butler matrix by 2 compared to its classical microstrip design counterpart at 2.4 GHz. The overall rectification efficiency and DC power patterns are reported for the elevation plane of one multidirectional rectenna at 2.4 GHz for an incident power density of 0.45 μW.cm-2. It is shown that the system can triple the DC output power compared to a 3-dipole counterpart occupying the same area. Furthermore, while the maximum harvesting capability at 1 μW.cm-2 does not exceed 28π %.steradian in the literature, it reaches 43.6π %.steradian with the proposed demonstrator

Analysis of a jet stream induced gravity wave associated with an observed ice cloud over Greenland

A polar stratospheric ice cloud (PSC type II) was observed by airborne lidar above Greenland on 14 January 2000. It was the unique observation of an ice cloud over Greenland during the SOLVE/THESEO 2000 campaign. Mesoscale simulations with the hydrostatic HRM model are presented which, in contrast to global analyses, are capable to produce a vertically propagating gravity wave that induces the low temperatures at the level of the PSC afforded for the ice formation. The simulated minimum temperature is ~8 K below the driving analyses and ~4.5 K below the frost point, exactly coinciding with the location of the observed ice cloud. Despite the high elevations of the Greenland orography the simulated gravity wave is not a mountain wave. Analyses of the horizontal wind divergence, of the background wind profiles, of backward gravity wave ray-tracing trajectories, of HRM experiments with reduced Greenland topography and of several diagnostics near the tropopause level provide evidence that the wave is emitted from an intense, rapidly evolving, anticyclonically curved jet stream. The precise physical process responsible for the wave emission could not be identified definitely, but geostrophic adjustment and shear instability are likely candidates. In order to evaluate the potential frequency of such non-orographic polar stratospheric cloud events, the non-linear balance equation diagnostic is performed for the winter 1999/2000. It indicates that ice-PSCs are only occasionally generated by gravity waves emanating from spontaneous adjustment.ISSN:1680-7375ISSN:1680-736

Folded Patch Antenna on Paper for RF Energy Harvesting and Sensing Applications

session: Antenna and PropagationInternational audienceThe design of antennas on cellulosic flexible materials such as paper can be very challenging because of the limited thickness and the high losses in the Radio Frequency (RF) domain. In this paper, a novel patch antenna with an origami structure is proposed to address the null radiation efficiency obtained with the conventional paper-based structure. As the electromagnetic waves mostly travel in the air, ideal conditions such as no loss and a low dielectric constant allow for the asymptotic value of directivity of microstrip antennas to be reached with a 63 % experimental radiation efficiency. This flexible antenna can be used for RF energy harvesting or sensing applications due to the sensitivity of paper on atmospheric conditions

Source Term Evaluation of the APE-RF System using DNS Data

Acoustic perturbation equations for reacting flows (APE-RF) in conjunction with direct numerical simulations (DNS) are used to investigate in detail the thermo-acoustic effects resulting from turbulent premixed flames. The basic procedure is a two-step DNS/APE-RF method, where the flow is simulated by direct numerical simulations and the acoustic analysis is performed using the APE-RF system. Based on the DNS data, the source terms of the APE-RF system can be thoroughly evaluated, since the full chemical reaction is taken into account in the DNS. The acoustic impact of several source mechanisms are investigated, such as the effect of unsteady heat release, that of heat flux, viscous effects, the effect of non-isomolar combustion, and that of species diffusion. The study shows the unsteady heat release to be the dominant source. All source terms but the heat diffusion term possess a monopole-like structure in the low frequency range. At high frequencies a multipole-like pattern is also determined for the sources due to species diffusion and viscous effects. This deviation from the monopole structure is caused by the chemical reaction time scales. It is shown in this study that the radiated acoustic energy is in good agreement comparing the impact of the total time derivative of the density as major source term with the unsteady heat release rate