Vector Shift Research Articles

Intra-left ventricular flow dynamics in patients with preserved and impaired left ventricular function: Analysis with 3D cine phase contrast MRI (4D-Flow).

To examine how left ventricular (LV) volume and function affect flow dynamics by analyzing 3D intra-LV vortex features using 4D-Flow. Twenty-one patients with preserved (LVEF > 60%) and 14 with impaired LV function (LVEF < 40%) underwent 4D-Flow (at 3T). In patients with preserved LV function, the intra-LV vortices developed in both the early and late diastolic phases. The shift of inflow vectors at the basal LV toward the posterior-lateral side of the LV and the mid-ventricular turn of inflow vectors toward the LV outflow could explain clearer vortex formation in the late diastolic phase. In patients with impaired LV function, the intra-LV vortices during the diastolic phase located at the more apical LV were larger and more spherically shaped. Both the distance to the vortex core and the vortex area correlated significantly with LV end-diastolic volume (r = 0.66 and 0.73), LVEF (r = -0.74 and -0.68), LV sphericity index (r = -0.60 and -0.65), and peak filling rate (r = -0.61 and -0.64), respectively (P < 0.01). The intra-LV vortices developed during the systolic phase in 10 cases. In those, some of the particles at the apical LV rotated within the LV, whereas in patients with preserved LV function, all of the particles were directed straight to the ascending aorta with accelerated flow velocity (256.8 ± 120.2 cm/s vs. 414.3 ± 88.2 cm/s, P < 0.01). Vortex formation during the diastolic phase may be critical for both LV filling and ejection. 4D-Flow showed the 3D alterations of intra-LV flow dynamics by LV dilatation and dysfunction in a noninvasive and comprehensive manner. J. Magn. Reson. Imaging 2016;44:1493-1503.

The Aharanov-Bohm Phase Shift and Magnetic Vector Potential “A” Could Accommodate for Optical Coupler, Digital-to-Analogue Magnetic Field Excess Correlations of Photon Emissions Within Living Aqueous Systems

Quantitative convergence for solutions involving electron drift velocity, the magnetic A vector and phase shifts reveal an increment of energy in the range of 10-20 J that could relate the Aharanov-Bohm phase modulation of the orbital frequency of a Bohr atom to the electron’s Compton wavelength. The universal persistence of 10-12 W per m2 whose energy applied the square of the hydrogen wavelength solves for the energy equivalence of the rest mass of an electron could set the conditions for excess correlations between electronic systems that produce magnetic fields through optocouplers. Experimental evidence and quantitative solutions indicate variations of the Lorentz Lemma and circularly rotating magnetic fields whose phase and group velocities are uncoupled could create the conditions for excess correlations. Modification of Basharov’s operator of resonance interaction for decoherence and entanglement in the radioactive decay of a diatomic system and Das and Misra’s estimates for the fractal charge of a photon strongly suggests that the efficacy for optocoupler circuits to generate non-local magnetic field effects in living and non-living aqueous systems originates from a single photon wave across the circuit’s p-n junctions. A review of the concepts and data indicate that excess correlations involving photons under optimal conditions are measureable within macrosystems

Need for New Islanding Detection Schemes and Prioritization with Generator Grid Code Requirements

New and forthcoming grid codes increasingly require fault-ride-through capabilities as well as utility grid supporting functionalities from distributed generators. However, these grid code requirements have been made mainly from transmission network stability point of view and less attention has been paid on potential effects on islanding detection and protection of distribution networks. Therefore, conflicts between traditional passive islanding detection methods, like voltage vector shift, and new grid code requirements may potentially exist. In this paper comparison of simultaneous values and behavior of frequency, rate-of-change-of-frequency and voltage vector shift was done by PSCAD simulations taking simultaneously into account generator grid code requirements. Simulation results confirmed that prioritization challenges between traditional passive islanding detection methods and grid code requirements are possible. Therefore, different prioritization possibilities including their benefits or drawbacks are presented at the end of the paper.

Simulation of tectonic evolution of the Kanto Basin of Japan since 1 Ma due to subduction of the Pacific and Philippine Sea plates and the collision of the Izu-Bonin arc

The Kanto Basin, the largest lowland in Japan, developed by flexure as a result of (1) the subduction of the Philippine Sea (PHS) and the Pacific (PAC) plates and (2) the repeated collision of the Izu-Bonin arc fragments with the Japanese island arc. Geomorphological, geological, and thermochronological data on vertical movements over the last 1My suggest that subsidence initially affected the entire basin after which the area of subsidence gradually narrowed until, finally, the basin began to experience uplift. In this study, we modeled the tectonic evolution of the Kanto Basin following the method of Matsu'ura and Sato (1989) for a kinematic subduction model with dislocations, in order to quantitatively assess the effects of PHS and PAC subduction. We include the steady slip-rate deficit (permanent locking rate at the plate interface) in our model to account for collision process. We explore how the latest collision of the Izu Peninsula block has been affected by a westerly shift in the PHS plate motion vector with respect to the Eurasian plate, thought to have occurred between 1.0–0.5Ma, using long-term vertical deformation data to constrain extent of the locked zone on the plate interface. We evaluated the change in vertical deformation rate for two scenarios: (1) a synchronous shift in the orientation of the locked zone as PHS plate motion shifts and (2) a delayed shift in the orientation of the locked zone following the shift in plate motion. Observed changes in the uplift/subsidence pattern are better explained by scenario (2), suggesting that recent (<1My) deformation in the Kanto Basin shows a lag in crustal response to the plate motion shift. We also calculated stress accumulation rates and found a good match with observed earthquake mechanisms, which shows that intraplate earthquakes serve to release stress accumulated through long-term plate interactions.

Wide-Area Phase-Angle Measurements for Islanding Detection—An Adaptive Nonlinear Approach

The integration of an ever-growing proportion of large-scale distributed renewable generation has increased the probability of maloperation of the traditional RoCoF and vector shift relays. With reduced inertia due to nonsynchronous penetration in a power grid, system-wide disturbances have forced the utility industry to design advanced protection schemes to prevent system degradation and avoid cascading outages leading to widespread blackouts. This paper explores a novel adaptive nonlinear approach applied to islanding detection, based on wide-area phase-angle measurements. This is challenging since the voltage phase angles from different locations exhibit not only strong nonlinear but also time-varying characteristics. The adaptive nonlinear technique, called moving window kernel principal component analysis, is proposed to model the time-varying and nonlinear trends in the voltage-phase angle data. The effectiveness of the technique is exemplified using DigSilent simulated cases and real test cases recorded from the Great Britain and Ireland power systems by the OpenPMU project.

Moving faults while unfaulting 3D seismic images

Unfaulting seismic images to correlate seismic reflectors across faults is helpful in seismic interpretation and is useful for seismic horizon extraction. Methods for unfaulting typically assume that fault geometries need not change during unfaulting. However, for seismic images containing multiple faults and, especially, intersecting faults, this assumption often results in unnecessary distortions in unfaulted images. We have developed two methods to compute vector shifts that simultaneously move fault blocks and the faults themselves to obtain an unfaulted image with minimal distortions. For both methods, we have used estimated fault positions and slip vectors to construct unfaulting equations for image samples alongside faults, and we have constructed simple partial differential equations for samples away from faults. We have solved these two different kinds of equations simultaneously to compute unfaulting vector shifts that are continuous everywhere except at faults. We have tested both methods on a synthetic seismic image containing normal, reverse, and intersecting faults. We also have applied one of the methods to a real 3D seismic image complicated by numerous intersecting faults.

Precision measurement of theRb87tune-out wavelength in the hyperfine ground stateF=1at 790 nm

We report on a precision measurement of the $D$ line tune-out wavelength of $^{87}$Rubidium in the hyperfine ground state $|F=1, m_F=0,\pm1 \rangle$ manifold at 790 nm, where the scalar ac Stark shifts of the $D_1$ and the $D_2$ lines cancel. This wavelength is sensitive to usually neglected contributions from vector and tensor ac Stark shifts, transitions to higher principle quantum numbers, and core electrons. The ac Stark shift is probed by Kapitza-Dirac scattering of a Rubidium Bose-Einstein condensate in a one-dimensional optical lattice in free space and controlled magnetic environment. The tune-out wavelength of the magnetically insensitive $m_F=0$ state was determined to 790.01858(23) nm with sub pm accuracy. An in situ absolute polarization, and magnetic background field measurement is performed by employing the ac vector Stark shift for the $m_F=\pm 1$ states. Comparing our findings to theory, we get quantitative insight into atomic physics beyond commonly used two-level atom approximations or the neglect of inner shell contributions.

Vector analysis of bladder cancer patient setup utilizing a magnetic resonance image-guided radiation therapy (MR-IGRT) system.

412 Background: Inter and intra-fraction anatomy changes in patients undergoing radiation therapy (RT) for bladder cancer (BC) are common but have thus far been studied with implanted fiducial markers, limited quality 2-D orthogonal films and computed tomography (CT). The adverse impact of daily set-up variation could be more significant than appreciated. Our goal was to employ the soft tissue imaging capabilities of an integrated magnetic resonance image-guided RT (MR-IGRT) system to analyze daily positioning. Methods: Fourteen patients with BC were treated on a MR-IGRT system. Patient setup was performed via volumetric MR imaging with a resolution of 0.15 x 0.15 cm. Alignment was performed according to skin marks then shifts assessed by comparing the treatment volume from the planning CT to the daily MR image. 240 pretreatment MR images were analyzed and 3 shifts were recorded for each image. A vector shift was calculated by combining the square root of the combined sum of the shifts squared. Number of times that the vector of combined shifts would have exceeded the planning tumor volume (PTV) was recorded. Results: Daily volumetric MR imaging allowed for accurate alignment and daily monitoring of bladder volume and normal tissue anatomy. Recorded shifts of the treated volume were 0.9±0.5 cm in the right/left direction, 0.7±0.3 cm in the anterior/posterior direction, and 0.7±0.4 cm in the cranio-caudal direction. In 66 (28%) of cases the vector shift was initially greater than the PTV margin. For 2 patients, pre-treatment MR imaging revealed the tumor reduced in size and dose to the bowel would have exceeded constraints, and treatment adaptation was performed to reduce normal tissue toxicity. Using CTCAE criteria, no grade 3 or higher toxicities have been reported. Conclusions: Accurate and reproducible treatment delivery is required to avoid marginal misses to the target volume as well as excess dose to normal tissue. MR-IGRT allows for excellent soft tissue visualization which enables for the avoidance of potential setups errors by allowing daily alignment changes to ensure the target is included in the PTV. It also allows the ability to make treatment changes based on anatomy variations.

ON THE HOTELLING’S T, MCUSUM AND MEWMA CONTROL CHARTS' PERFORMANCE WITH DIFFERENT VARISBILITY SOURCES: A SIMULATION STUDY

This work is a simulation study to investigate the sensitivity of multivariate control charts for monitoring mean vectors in a bivariate Gaussian process with individual observations. The multivariate cumulative sum (MCUSUM), the multivariate exponentially weighted moving average (MEWMA) and Hotelling’s T charts are selected for analysis due to their common dependency on the noncentrality parameter. The chart performance is evaluated through the average run length (ARL) or the average time to signal. The impact of utilising in-control limits computed from known parameters or Phase I sample estimates is considered for mean vector shifts. Although designed to monitor mean vectors, the sensibility of the control charts is additionally analysed through different variability sources, including the mixing effect of mean vector shifts with increasing variances or positive autocorrelation in the out-of-control process.

Revisiting Human Cholesterol Synthesis and Absorption: The Reciprocity Paradigm and its Key Regulators.

Hypercholesterolemia is a major risk factor for cardiovascular disease. Cholesterol homeostasis in the body is governed by the interplay between absorption, synthesis, and excretion or conversion of cholesterol into bile acids. A reciprocal relationship between cholesterol synthesis and absorption is known to regulate circulating cholesterol in response to dietary or therapeutic interventions. However, the degree to which these factors affect synthesis and absorption and the extent to which one vector shifts in response to the other are not thoroughly understood. Also, huge inter-individual variability exists in the manner in which the two systems act in response to any cholesterol-lowering treatment. Various factors are known to account for this variability and in light of recent experimental advances new players such as gene-gene interactions, gene-environmental effects, and gut microbiome hold immense potential in offering an explanation to the complex traits of inter-individual variability in human cholesterol metabolism. In this context, the objective of the present review is to provide an overview on cholesterol metabolism and discuss the role of potential factors such as genetics, epigenetics, epistasis, and gut microbiome, as well as other regulators in modulating cholesterol metabolism, especially emphasizing the reciprocal relationship between cholesterol synthesis and absorption. Furthermore, an evaluation of the implications of this push-pull mechanism on cholesterol-lowering strategies is presented.

Synchrophasor-Based Islanding Detection for Distributed Generation Systems Using Systematic Principal Component Analysis Approaches

Systematic principal component analysis (PCA) methods are presented in this paper for reliable islanding detection for power systems with significant penetration of distributed generations (DGs), where synchrophasors, recorded by phasor measurement units, are used for system monitoring. Existing islanding detection methods, such as rate-of-change-of-frequency and vector shift are fast for processing local information; however, with the growth in installed capacity of DGs, they suffer from several drawbacks. Incumbent genset islanding detection cannot distinguish a system-wide disturbance from an islanding event, leading to maloperation. The problem is even more significant when the grid does not have sufficient inertia to limit frequency divergences in the system fault/stress due to the high penetration of DGs. To tackle such problems, this paper introduces PCA methods for islanding detection. A simple control chart is established for intuitive visualization of the transients. A recursive PCA scheme is proposed as a reliable extension of the PCA method to reduce the false alarms for time-varying process. To further reduce the computational burden, the approximate linear dependence condition errors are calculated to update the associated PCA model. The proposed PCA and RPCA methods are verified by detecting abnormal transients occurring in the U.K. utility network.

Stopping light in an active medium

On the basis of work done by Lorentz force and Maxwell’s equations, energy conversion relationships of electromagnetic fields in the dispersive and absorptive media are analyzed. Then new definitions of stored and lossy energy densities are proposed, respectively. Furthermore, it is predicted that light may stop steadily in an active medium when both real part of impedance and imaginary part of wave vector equal zero, which corresponds to a case that time-dependent Poynting vector shift forward and then turn backward periodically.

Polarizabilities of theSr87clock transition

In this paper, we propose an in-depth review of the vector and tensor polarizabilities of the two energy levels of the 87Sr clock transition whose measurement was reported in [P. G. Westergaard et al., Phys. Rev. Lett. 106, 210801 (2011)]. We conduct a theoretical calculation that reproduces the measured coefficients. In addition, we detail the experimental conditions used for their measurement in two Sr optical lattice clocks, and exhibit the quadratic behaviour of the vector and tensor shifts with the depth of the trapping potential and evaluate their impact on the accuracy of the clock.

Inhomogeneous broadening of optical transitions of 87Rb atoms in an optical nanofiber trap

We experimentally demonstrate optical trapping of atoms using a two-color evanescent field around an optical nanofiber. In our trapping geometry, a blue-detuned traveling wave whose polarization is nearly parallel to the polarization of a red-detuned standing wave produces significant vector light shifts that lead to broadening of the absorption profile of a near-resonant beam at the trapping site. A model that includes scalar, vector, and tensor light shifts of the probe transition - from the trapping beams, weighted by the temperature-dependent position of the atoms in the trap, qualitatively describes the observed asymmetric profile and explains differences with previous experiments that used Cs atoms. The model provides a consistent way to extract the number of atoms in the trap.

Evaluation of setup uncertainties for single-fraction SRS by comparing two different mask-creation methods

The purpose of this study was to evaluate the setup uncertainties for single-fraction stereotactic radiosurgery (SF-SRS) based on clinical data with two different mask-creation methods using pretreatment con-beam computed tomography imaging guidance. Dedicated frameless fixation Brain- LAB masks for 23 patients were created as a routine mask (R-mask) making method, as explained in the BrainLAB’s user manual. Alternative masks (A-masks), which were created by modifying the cover range of the R-masks for the patient’s head, were used for 23 patients. The systematic errors including these for each mask and stereotactic target localizer were analyzed, and the errors were calculated as the means ± standard deviations (SD) from the left-right (LR), superior-inferior (SI), anterior-posterior (AP), and yaw setup corrections. In addition, the frequencies of the threedimensional (3D) vector length were analyzed. The values of the mean setup corrections for the R-mask in all directions were < 0.7 mm and < 0.1°, whereas the magnitudes of the SDs were relatively large compared to the mean values. In contrast, the means and SDs of the A-mask were smaller than those for the R-mask with the exception of the SD in the AP direction. The means and SDs in the yaw rotational direction for the R-mask and the A-mask system were comparable. 3D vector shifts of larger magnitude occurred more frequently for the R-mask than the A-mask. The setup uncertainties for each mask with the stereotactic localizing system had an asymmetric offset towards the positive AP direction. The A-mask-creation method, which is capable of covering the top of the patient’s head, is superior to that for the R-mask, so the use of the A-mask is encouraged for SF-SRS to reduce the setup uncertainties. Moreover, careful mask-making is required to prevent possible setup uncertainties.

Systematic errors in lung stereotactic body radiation therapy (SBRT): a caution on mixing and matching target delineation methods and planning CTs

Precise tumor alignment is vital in lung stereotactic body radiotherapy (SBRT). Differences in center of mass (COM) resulting from mixing and matching target delineation methods, and planning image datasets could introduce systematic errors. Thirty consecutive lung SBRT patients were simulated with free-breathing CT (FBCT), maximum inhalation and exhalation breath hold CT (BHCT), and 4D-CT. Four planning target volumes (PTV) were created: 5/10-mm expansion from the gross tumor volume (GTV) in FBCT (PTVFBCT), 5-mm expansion from the internal target volume (ITV) in BHCT (PTVBHCT), 5-mm expansion from the ITV in the maximum intensity projection (PTVMIP), and 5-mm expansion from the ITV in 4D-CT (PTV4D-CT). Using average intensity projection CT (AIP-CT) or FBCT as the reference images, PTVs were transferred after bony registration to compare COMs. When AIP-CT was used as reference, the mean COM vector shifts of the PTVFBCT, PTVBHCT, and PTV4D-CT were 2.94 mm (p = 0.0094), 4.35 mm (p = 0.0001), and 1.45 mm (p = 0.57), respectively, relative to the COM of the GTV on AIP-CT. When FBCT was used as reference, the mean COM vector shifts of the PTVBHCT, PTVMIP, and PTV4D-CT were 3.6 mm (p = 0.0006), 2.78 mm (p = 0.003), and 2.94 mm (p = 0.002) relative to the GTV on FBCT, respectively. Depending on the reference images used, the COMs of the PTVFBCT, PTVBHCT, and PTV4D-CT are inconsistent, exhibiting significant shifts relative to each other. To avoid possible systematic localization errors, we recommend using 4D-CT/MIP for target delineation and AIP-CT for planning and alignment.

Use of implanted gold fiducial markers with MV-CBCT image-guided IMRT for pancreatic tumours.

Visualisation of soft tissues such as pancreatic tumours by mega-voltage cone beam CT (MV-CBCT) is frequently difficult and daily localisation is often based on more easily seen adjacent bony anatomy. Fiducial markers implanted into pancreatic tumours serve as surrogates for tumour position and may more accurately represent absolute tumour position. Differences in daily shifts based on alignment to implanted fiducial markers vs. alignment to adjacent bony anatomy were compared. Gold fiducial markers were placed into the pancreatic tumour under endoscopic ultrasound (EUS) guidance in 12 patients. Patients subsequently received image-guided intensity-modulated radiation therapy (IG-IMRT). MV-CBCT was performed prior to each fraction and isocentre shifts were performed based on alignment to the fiducial markers. We retrospectively reviewed archived MV-CBCT datasets and calculated shift differences in the left-right (LR), superior-inferior (SI) and anterior-posterior (AP) axes relative to shifts based on alignment to adjacent bony anatomy. Two hundred forty-three fractions were analysed. The mean absolute difference in isocentre shifts between the fiducial markers and those aligned to bony anatomy was 3.4 mm (range 0-13 mm), 6.3 mm (range 0-21 mm) and 2.6 mm (range 0-12 mm), in LR, SI and AP directions, respectively. The mean three-dimensional vector shift difference between markers vs. bony anatomy alignment was 8.6 mm. These data suggest that fiducial markers used in conjunction with MV-CBCT improve the accuracy of daily target delineation compared with localisation using adjacent bony anatomy and that gold fiducial markers using MV-CBCT alignment are a viable option for target localisation during IG-IMRT.

MOLTOOLS: a workshop on “Molecular tools for monitoring marine invasive species”

The 2011–2014 European Community project VECTORS (‘‘Vectors of Change in Oceans and SeasMarine Life, Impact on Economic Sectors’’) was an integrated, multidisciplinary European project which aimed to improve our understanding of how environmental anthropogenic drivers are impacting European marine ecosystems now and in the future. VECTORS investigated how these changes may affect marine biodiversity and ecosystem functioning, the range of goods and services provided by the oceans, the resulting socio-economic impacts and some possible future scenarios for mitigation and adaptation. The VECTORS Work Package WP2.1 (Mechanisms of Change: Outbreaks and Invasives) was committed to identifying mechanisms of species outbreaks and invasions and introduction vectors as both symptoms and drivers of change in European marine ecosystems. VECTORS particularly focused on native outbreak-forming species (OFS) and invasive alien species (IAS) (Box 1) to deliver new information on (1) IAS and OFS distribution in European seas, (2) stochastic and deterministic drivers of invasions and ecophysiological features boosting regime shifts of marine communities, (3) sources and vectors of bioinvasions, and (4) consequences of bioinvasions, in terms of impact on ecosystem functioning and services. These studies provided a substantive contribution to the understanding of the ecological conditions in which outbreaks and alien invasions are more likely to occur, and the determination of critical thresholds/tipping points that mark alternative regime shifts in community structure and organization. The progressive reduction in the inherent costs of molecular data over the past 20 years, along with rapid recent technological and analytical developments, has resulted in molecular methods becoming an inescapable component of investigation on biological invasions, from simple biodiversity assessment to historical reconstruction of invasion histories. Within this context, 60 participants frwom 14 nations gathered in Lecce, Italy on 12–14th September 2012 for MOLTOOLS (Fig. 1), a dedicated workshop to discuss and promote the use of molecular tools for monitoring and understanding marine invasive species. The workshop was designed to address several key questions regarding mechanisms and management J. A. Darling National Exposure Research Laboratory, United States Environmental Protection Agency, Durham, NC 27713, USA

Species composition, seasonal occurrence, habitat preference and altitudinal distribution of malaria and other disease vectors in eastern Nepal

BackgroundIt is increasingly recognized that climate change can alter the geographical distribution of vector-borne diseases (VBDs) with shifts of disease vectors to higher altitudes and latitudes. In particular, an increasing risk of malaria and dengue fever epidemics in tropical highlands and temperate regions has been predicted in different climate change scenarios. The aim of this paper is to expand the current knowledge on the seasonal occurrence and altitudinal distribution of malaria and other disease vectors in eastern Nepal.MethodsAdult mosquitoes resting indoors and outdoors were collected using CDC light trap and aspirators with the support of flash light. Mosquito larvae were collected using locally constructed dippers. We assessed the local residents’ perceptions of the distribution and occurrence of mosquitoes using key informant interview techniques. Generalized linear models were fitted to assess the effect of season, resting site and topography on the abundance of malaria vectors.ResultsThe known malaria vectors in Nepal, Anopheles fluviatilis, Anopheles annularis and Anopheles maculatus complex members were recorded from 70 to 1,820 m above sea level (asl). The vectors of chikungunya and dengue virus, Aedes aegypti and Aedes albopictus, the vector of lymphatic filariasis, Culex quinquefasciatus, and that of Japanese encephalitis, Culex tritaeniorhynchus, were found from 70 to 2,000 m asl in eastern Nepal. Larvae of Anopheles, Culex and Aedes species were recorded up to 2,310 m asl. Only season had a significant effect on the abundance of An. fluviatilis, season and resting site on the abundance of An. maculatus complex members, and season, resting site and topography on the abundance of An. annularis. The perceptions of people on mosquito occurrence are consistent with entomological findings.ConclusionsThis study provides the first vertical distribution records of vector mosquitoes in eastern Nepal and suggests that the vectors of malaria and other diseases have already established populations in the highlands due to climatic and other environmental changes. As VBD control programmes have not been focused on the highlands of Nepal, these findings call for actions to start monitoring, surveillance and research on VBDs in these previously disease-free, densely populated and economically important regions.

Altitudinal shift of malaria vectors and malaria elimination in Nepal

Background Malaria elimination is a goal of many endemic countries with the ultimate goal of global malaria eradication. Based on the achievements the country has made over the last decade, Nepal has been preparing for a malaria pre-elimination phase since 2011 with the ambitious vision of a malaria-free Nepal by 2026. However, a number of challenges have been identified in recent studies including high rates of relapse/ re-infection with Plasmodium vivax [1], persistence of Plasmodium falciparum and clinically suspected malaria, continuous import of malaria cases, underreporting of mixed infections (P. falciparum and P. vivax), and climate change [2]. In this study, we report, in addition, on altitudinal shifts of malaria vectors in Nepal.