A5006105229- Physics of Superconductivity and Magnetism
- Viral Infections and Immunology Research
- Viral gastroenteritis research and epidemiology
- Advanced Condensed Matter Physics
- X-ray Diffraction in Crystallography
- High-pressure geophysics and materials
- Animal Disease Management and Epidemiology
- COVID-19 epidemiological studies
- Theoretical and Computational Physics
- Celiac Disease Research and Management
- Mosquito-borne diseases and control
- Crystal Structures and Properties
- Data-Driven Disease Surveillance
- Inorganic Fluorides and Related Compounds
- Copper-based nanomaterials and applications
- Advanced Semiconductor Detectors and Materials
- COVID-19 Impact on Reproduction
- Virology and Viral Diseases
- Crystallography and Radiation Phenomena
- Parasite Biology and Host Interactions
- Assisted Reproductive Technology and Twin Pregnancy
- Advanced NMR Techniques and Applications
- Family Dynamics and Relationships
- Hemoglobinopathies and Related Disorders
- Child Nutrition and Water Access
Gates Foundation
2020-2023
Institute for Disease Modeling
2014-2023
Seattle University
2022
Bellevue Hospital Center
2014-2019
Intellectual Ventures (United States)
2014-2016
Stanford University
2005-2010
Palo Alto University
2008
Individual-based models provide modularity and structural flexibility necessary for modeling of infectious diseases at the within-host population levels, but are challenging to implement. Levels complexity can exceed capacity timescales students trainees in most academic institutions. Here we describe process advantages a multi-disease framework approach developed with formal software support. The epidemiological software, EMOD, has undergone decade development. It is structured so that...
Pakistan is one of only three countries where poliovirus circulation remains endemic. For the Polio Eradication Program, identifying high risk districts essential to target interventions and allocate limited resources. Using a hierarchical Bayesian framework we developed spatial Poisson hurdle model jointly probability or more paralytic polio cases, number cases that would be detected in event an outbreak. Rates underimmunization, routine immunization, population immunity, as well...
The compound ${\text{HgBa}}_{2}{\text{CuO}}_{4+\ensuremath{\delta}}$ (Hg1201) exhibits a simple tetragonal crystal structure and the highest superconducting transition temperature $({T}_{c})$ among all single Cu-O layer cuprates, with ${T}_{c}=97\text{ }\text{K}$ (onset) at optimal doping. Due to lack of sizable crystals, experimental work on this very attractive system has been significantly limited. Thanks recent breakthrough in growth, such crystals have now become available. Here we...
Background The polio environmental surveillance (ES) system has been an incredible tool for advancing eradication efforts because of its ability to highlight the spatial and temporal extent poliovirus circulation. While ES often outperforms, or is more sensitive than AFP surveillance, sensitivity not well characterized. Fundamental uncertainty site makes it difficult interpret results from ES, particularly negative results. Methods findings To study sensitivity, we used data Afghanistan...
The results of model calculations using exact diagonalization reveal the orbital character states associated with different Raman loss peaks in Cu $K$-edge resonant inelastic x-ray scattering (RIXS) from ${\mathrm{La}}_{2}{\mathrm{CuO}}_{4}$. includes electronic orbitals necessary to highlight nonlocal Zhang-Rice singlet, charge transfer, and $d\mathrm{\text{\ensuremath{-}}}d$ excitations, as well apical oxygen $2{p}_{z}$ character. dispersion these excitations is discussed prospects for...
The oral polio vaccine (OPV) contains live-attenuated polioviruses that induce immunity by causing low virulence infections in recipients and their close contacts. Widespread immunization with OPV has reduced the annual global burden of paralytic poliomyelitis a factor 10,000 or more driven wild poliovirus (WPV) to brink eradication. However, instances have so far been rare, can paralyze generate vaccine-derived outbreaks. To complete eradication, use should eventually cease, but doing will...
One of the challenges facing Global Polio Eradication Initiative is efficiently directing limited resources, such as specially trained personnel, community outreach activities, and satellite vaccinator tracking, to most at-risk areas maximize impact interventions. A validated predictive model wild poliovirus circulation would greatly inform prioritization efforts by accurately forecasting at greatest risk, thus enabling effect program Using Nigerian acute flaccid paralysis surveillance data...
Wild type 2 poliovirus was last observed in 1999. The Sabin-strain oral polio vaccine (OPV2) critical to eradication, but it is known revert a neurovirulent phenotype, causing vaccine-associated paralytic poliomyelitis. OPV2 also transmissible and can establish circulating lineages, called vaccine-derived polioviruses (cVDPVs), which cause outbreaks. Thus, April 2016, removed from immunization activities worldwide. Interrupting transmission of cVDPV2 lineages that survive cessation will...
Measles causes significant childhood morbidity in Nigeria. Routine immunization (RI) coverage is around 40% country-wide, with very high levels of spatial heterogeneity (3–86%), supplemental activities (SIAs) at 2-year or 3-year intervals. We investigated cost savings and burden reduction that could be achieved by adjusting the inter-campaign interval region. modeled 81 scenarios; permuting SIA calendars every one, two, three years each four regions Nigeria (North-west, North-central,...
We report a Cu -edge resonant inelastic x-ray scattering (RIXS) study of charge-transfer excitations in the 2-8 eV range structurally simple compound HgBa(2)CuO(4+delta) at optimal doping (T(c)=96.5 K). The spectra exhibit significant dependence on incident photon energy which we carefully utilize to resolve multiplet weakly dispersive (<0.5 eV) electron-hole excitations, including mode 2 eV. observation this excitation suggests existence remnant gap deep superconducting phase. Quite...
We present a resonant inelastic scattering (RIXS) study using of ${\text{CuB}}_{2}{\text{O}}_{4}$, which contains lattice ${\text{CuO}}_{4}$ plaquettes electronically isolated by ${\text{B}}^{+3}$ ions. The observed $\text{Cu}\text{ }K$-edge spectra show small number well-separated features, and the simple electronic structure ${\text{CuB}}_{2}{\text{O}}_{4}$ allows us to explore RIXS phenomenology. find low-energy feature that cannot be attributed same charge-transfer excitation discussed...
Understanding the environmental conditions of disease transmission is important in study vector-borne diseases. Low- and middle-income countries bear a significant portion burden; but data about weather those can be sparse difficult to reconstruct. Here, we describe methods assemble high-resolution gridded time series sets air temperature, relative humidity, land rainfall for such areas; test these on island Madagascar. Air temperature humidity were constructed using statistical...
We present a detailed Cu $K$-edge resonant inelastic x-ray scattering (RIXS) study of the Mott insulator ${\mathrm{La}}_{2}\mathrm{Cu}{\mathrm{O}}_{4}$ in $1--7\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ energy loss range. As initially found for high-temperature superconductor $\mathrm{Hg}{\mathrm{Ba}}_{2}\mathrm{Cu}{\mathrm{O}}_{4+\ensuremath{\delta}}$, spectra exhibit multiplet weakly dispersive electron-hole excitations, which are revealed by utilizing subtle dependence cross section on...
The world is closer than ever to a polio-free Africa. In this end-stage, it important ensure high levels of population immunity prevent polio outbreaks. Here, we introduce new method assessing vaccination campaign effectiveness and estimating at the district-level. We demonstrate how approach can be used plan campaigns prospectively better manage in Northern Nigeria.Using Nigerian acute flaccid paralysis surveillance data from 2004-2014, developed Bayesian hierarchical model compared...
We present a study of the charge-transfer excitations in undoped ${\text{Nd}}_{2}{\text{CuO}}_{4}$ using resonant inelastic x-ray scattering (RIXS) at $\text{Cu}\text{ }K$-edge. At Brillouin zone center, azimuthal scans that rotate incident-photon polarization within ${\text{CuO}}_{2}$ planes reveal weak fourfold oscillations. A comparison spectra taken different zones reveals spectral weight decrease high-energy loss from forward- to back-scattering. show these are scattered-photon effects...
Since the launch of Global Polio Eradication Initiative, all but three countries (Nigeria, Pakistan, and Afghanistan) have apparently interrupted wild poliovirus (WPV) transmission, only one serotypes has been reported globally since 2012. Countrywide supplemental immunization campaigns in Nigeria produced dramatic reduction WPV Type 1 paralysis cases 2010 compared to 2000's, WPV1 not observed July 24, 2014. This article presents development calibration a spatial metapopulation model...
The globally synchronized removal of the attenuated Sabin type 2 strain from oral polio vaccine (OPV) in April 2016 marked a major change vaccination policy. This will provide significant reduction burden vaccine-associated paralytic (VAPP), but may increase risk circulating vaccine-derived poliovirus (cVDPV2) outbreaks during transition period. can be monitored by tracking disappearance Sabin-like (SL2) using data surveillance system. We studied SL2 prevalence 17 countries Africa and Asia,...
Important advances are being made in the fight against communicable diseases by using new digital tools. While they can be a challenge to deploy at-scale, GPS-enabled smartphones, electronic dashboards and computer models have multiple benefits. They facilitate program operations, lead insights about disease transmission support strategic planning. Today, tools such as these used vaccinate more children polio Nigeria, reduce malaria burden Zambia help predict spread of Ebola epidemic West Africa.
Abstract The behavioral and biological underpinnings of family planning (FP) unfold on an individual level, across a full reproductive life course, within complex system social structural constraints. Yet, much the existing FP modeling landscape has focused solely macro- or population-level dynamics planning. There is need for individual-based approach to provide deeper understanding how intertwined with individuals’ lives health at micro-level, which can contribute more effective,...
In this paper, we discuss our recent Cu K-edge resonant inelastic x-ray scattering (RIXS) results for CuB2O4, a model system consisting of electronically isolated CuO4 plaquettes, which exhibits anomalies in the incident photon energy dependence that are not captured by electron-only models. We show these anomalous features can be qualitatively described extending considerations to include lattice degrees freedom. Our findings have important general implications interpretation RIXS...
Background Guinea worm ( Dracunculus medinensis ) was detected in Chad 2010 after a supposed ten-year absence, posing challenge to the global eradication effort. Initiation of village-based surveillance system 2012 revealed substantial number dogs infected with worm, raising questions about paratenic hosts and cross-species transmission. Methodology/principal findings We coupled genomic case data from 2012-2018 investigate modes transmission between dog human geographic connectivity worms....
Abstract In Pakistan, annual poliovirus investment decisions drive quantities of supplemental immunization campaigns districts receive. this article, we assess whether increased spending on surveillance is associated with greater likelihood correctly identifying at high risk polio assignment an elevated “risk ranking.” We reviewed programmatic documents from Pakistan for the period 2012–2017, recording had been classified as “high risk” or “low in each year. Through document review,...