Population Of Small Particles Research Articles

Abstract 17049: Specific Subspecies of High Density Lipoprotein are Associated With Arterial Stiffness in Youth With and Without Diabetes

Introduction: Early vascular aging (EVA), a risk factor for cardiovascular disease (CVD), is evident in youth with diabetes. The mechanisms responsible for EVA are not well understood. Causal relationship of HDL-C with CVD is doubtful, but HDL particle concentration (HDL-P) and HDL function (cholesterol efflux capacity, CEC) are associated with incident and prevalent CVD independent of HDL-C. We investigated whether these metrics associate with EVA in youth. Methods: We studied three cohorts of youth with T1D (n=173), T2D (n=214) and healthy controls (n=116). We quantified total HDL-P and 6 HDL subspecies by differential ion mobility, serum HDL CEC (total and ABCA1-specific), and investigated their association with arterial stiffness (tonometric carotid-femoral pulse wave velocity, PWV) with multivariate regression. Results: PWV was not associated with total HDL-P in any of the three groups, but was associated positively with concentration of extra-small (xsHDL, 7.6nm, r=0.22, P=0.004) in T1D, small (sHDL, 8.2nm) particles in T1D (r=0.31, P<0.0001) and T2D (r=0.17, P=0.02), and negatively with large HDL particles (lHDL, 11.5 nm) in T1D (r=-0.19, P=0.01). None of the HDL subspecies associated with PWV in healthy subjects. The association of sHDL with PVW remained significant after adjustment for age, sex, BMIz, mean arterial pressure (MAP), and diabetes status when analyzing T1D and controls or T2D and control subjects (Table 1). Both HDL-CEC metrics were significantly associated with higher PWV in T1D cohort but not T2D cohort, however, in multivariate models neither remained significant after adjusting the model for MAP (Table 1). Conclusions: A specific population of small HDL particles, but not HDL CEC, is associated with EVA, a predictor of CVD, independent of traditional risk factors and distending pressure (MAP). How the small HDL particles relate to EVA and whether they may be a novel target for intervention to prevent EVA in youth remains to be investigated.

A study of dispersion of gunshot residue from a frequently used Serbian ammunition cal. 7.65 mm to support selected aspects of casework in North Macedonia

The subject of this research was the inorganic gunshot residue component collected from shooting patterns obtained on woven cotton cloth using a Pietro Beretta model 70 pistol, cal. 7.65 mm and Serbian ammunition for the following muzzle-to-target distances: 25, 50, 75, 100 and 125 cm. For each distance, three rounds of shooting were performed. Particles were lifted within a 10 cm radius of the projectile entrance and automatically analyzed using a scanning electron microscope coupled with an energy dispersion X-ray spectrometry. The obtained data on the populations of particles were analyzed taking into account their numbers, chemical classes and sizes. The results showed an apparent maximum incidence within all particles containing barium at about 50 cm distance. Also, lead particles revealed a distinct behaviour, being dominant at a 25 cm distance, falling below the other chemical classes, and finally becoming dominant again at 125 cm. The analysis of the frequency of occurrence of particles sorted according to their sizes confirmed that the small particle population is the largest, and their distribution in function of the equivalent circle diameter is exponential-like. The obtained results provided knowledge on the distribution of particles in the vicinity of the tested firearm and ammunition cal. 7.65 mm which generally corroborates with similarly studied GSR distributions obtained for the use of pistols cal. 9 mm. This information, together with the examinations of gunshot damages and other types of residues such as soot or unburned propellant grains may support qualitative inferences on shooting distance estimation, especially in cases, when the firearm and cartridges are not available to perform test shooting. In such cases even roughly estimated shooting distance can be helpful, e.g. for confirming or excluding the possibility of self-inflicted injuries or suicide and infer on the mutual position of the shooting stage actors. An example of casework that illustrates intermediate shooting distance estimation is presented.

Bimodal high solids content latices using RAFT‐mediated polymerization‐induced self‐assembly and semi‐batch emulsion polymerization

AbstractThis work focuses on increasing the solids content of water‐based coating materials such as paints, other coatings or adhesives while attempting to reduce the amount of surfactant in the final latex. The synthesis of a latex with a bimodal particle size distribution was carried out by combining RAFT and classical emulsion polymerization processes. By employing the RAFT polymerization, the population of small particles was created by self‐ordering the block copolymer chains, consisting of a hydrophilic block based on methacrylic acid or sodium 4‐styrenesulfonate and another hydrophobic block based on styrene. The final latex was made by adding a pre‐emulsion prepared from the latex of small particles and a mixture of monomers and surfactants to the latex of large particles made via conventional emulsion polymerization. The final bimodal latex thus obtained had a solids content of 65% mass with a viscosity value of around 2.0 Pa.s at a shear rate of 20 s−1.

Contact statistics in populations of noninteracting random walkers in two dimensions.

The interaction between individuals in biological populations, dilute components of chemical systems, or particles transported by turbulent flows depends critically on their contact statistics. This work clarifies those statistics under the simplifying assumptions that the underlying motions approximate a Brownian random walk and that the particles can be treated as noninteracting. We measure the contact-interval (also called the waiting-time or interarrival-time), contact-count, and contact-duration distributions in populations of individuals undergoing noninteracting continuous-space-time random walks on a periodic two-dimensional plane (a torus) as functions of the population number density, walker radius, and random-walk step size. The contact-interval is exponentially distributed for times longer than the ballistic mean-free-collision time but not for times shorter than that, and the contact duration distribution is strongly peaked at the ballistic-crossing time for head-on collisions when the ballistic-crossing time is short compared to the mean step duration. While successive contacts between individuals are independent, the probability of repeat contact decreases with time after a previous contact. This leads to a negative duration dependence of the waiting-time interval and overdispersion of the contact-count probability density function for all time intervals. The paper demonstrates that for populations of small particles (with a walker radius that is small compared to the mean-separation or random-walk step size), the ballistic mean-free-collision interval, the ballistic-crossing time, and the random-walk-step duration can be used to construct temporal scalings which allow for common waiting-time, contact-count, and contact-duration distributions across different populations. Semi-analytic approximations for both the waiting-time and contact-duration distributions are also presented.

Evaporation-driven self-assembly of binary and ternary colloidal polymer nanocomposites for abrasion resistant applications

We harness the self-assembly of aqueous binary latex/silica particle blends during drying to fabricate films segregated by size in the vertical direction. We report for the first time the experimental drying of ternary colloidal dispersions and demonstrate how a ternary film containing additional small latex particles results in improved surface stability and abrasion resistance compared with a binary film. Through atomic force microscopy (AFM) and energy-dispersive X-ray spectroscopy (EDX), we show that the vertical distribution of filler particles and the surface morphologies of the films can be controlled by altering the evaporation rate and silica volume fraction. We report the formation of various silica superstructures at the film surface, which we attribute to a combination of diffusiophoresis and electrostatic interactions between particles. Brownian dynamics simulations of the final stages of solvent evaporation provide further evidence for this formation mechanism. We show how an additional small latex particle population results in an increased abrasion resistance of the film without altering its morphology or hardness. Our work provides a method to produce water-based coatings with enhanced abrasion resistance as well as valuable insights into the mechanisms behind the formation of colloidal superstructures.

Acoustic attenuation spectroscopy and helium ion microscopy study of rehydration of dairy powder

Complete hydration is essential for the production of structured dairy products from powders. It is essential that the ingredients used hydrate completely. Determination of an end point of rehydration is non-trivial, but ultrasound-based methodologies have demonstrated potential in this area and are well suited to measuring bulk samples in situ. Here, acoustic attenuation spectroscopy (AAS) is used to monitor rehydration of skim milk powder, and recombined systems of micellar casein isolate with lactose and whey protein isolate. Dynamic light scattering, zeta-potential measurements and AAS as a function of pH characterise each component around its isoelectric point to assess its functionality. Scanning helium ion microscopy was used to image the dry powders, without any conductive coating, producing resolution equivalent to scanning electron microscopy, but with much larger focal lengths and fewer imaging artefacts. Imaging the powders provides information on particle size and morphology which can affect dissolution behaviour. Reconstituted skim milk powder and recombined samples were monitored showing there are changes occurring over several hours. Attenuation coefficients are shown to predict the end point of hydration. Model fitting is used to extract volume fractions and average particle sizes of large and small particle populations in recombined samples over time. AAS is demonstrated to be capable of tracking the dynamics in rehydrating dispersions over time. Physical parameters such as the volume fraction and particle size of the dispersed phase can be determined.

Interaction between casein and rice glutelin: Binding mechanisms and molecular assembly behaviours

The present study investigated the interaction between acid casein and rice glutelin (RG) under neutral conditions. Large particle populations contain casein-RG complex which consisted of β-casein, αs1-casein, and RG was formed. The results of multispectral studies indicated that the peptide chain and secondary structure of casein did not change during the binding process. Besides, the binding behaviours seemed to be closely related to the surface hydrophobic region of RG. Thermodynamic parameter calculations showed that the main driving forces behind this structure formation were the hydrogen bonds and van der Waals forces. On the other hand, the addition of RG caused the generation of small particle populations (~20 nm) which mainly composed of κ-casein and αs2-casein, and such small particle populations maintained aggregation through residual calcium. Moreover, it is noting that these two particle populations can coexist stably, this finding will provide an avenue to produce, by design, casein nanoparticles.

The Role of FeTi Addition to Micro-inclusions in the Production of ULC Steel Grades via the RH Process Route

In the production of ULC steel grades via the RH process route, Al is added first for deoxidation after the end of decarburization and FeTi follows after a certain period of separation of alumina particles and the related reduction of the total oxygen content. The FeTi addition is well known to cause clogging problems in the following casting process.The analysis of plant data by voestalpine Stahl in Linz indicates an increasing clogging tendency with a higher Ti/Al ratio in the steel. Automated SEM/EDS investigations on lollipop samples show the existence of a newly nucleated Ti-containing alumina particle population after the FeTi addition. These particles are comparably smaller than the alumina particles and, even if thermodynamically unstable, they still exist as a large population of small particles in samples taken from the tundish.The addition of Al and FeTi into a molten steel sample with controlled initial oxygen activity for varying Ti/Al ratios was simulated in laboratory scale afterwards. Just like in the plant, a new population of small Ti-containing alumina particles nucleates, with the size and number depending on the Ti/Al ratio in the melt.Laboratory experiments and plant observations are in consistence with each other and indicate—for the underlying process route and process parameters—some countermeasures for the better control of clogging.

Micrometeoroid Events in LISA Pathfinder

Abstract The zodiacal dust complex, a population of dust and small particles that pervades the solar system, provides important insight into the formation and dynamics of planets, comets, asteroids, and other bodies. We present a new set of data obtained from direct measurements of momentum transfer to a spacecraft from individual particle impacts. This technique is made possible by the extreme precision of the instruments flown on the LISA Pathfinder spacecraft, a technology demonstrator for a future space-based gravitational wave observatory. Pathfinder employed a technique known as drag-free control that achieved rejection of external disturbances, including particle impacts, using a micropropulsion system. Using a simple model of the impacts and knowledge of the control system, we show that it is possible to detect impacts and measure properties such as the transferred momentum, direction of travel, and location of impact on the spacecraft. In this paper, we present the results of a systematic search for impacts during 4348 hr of Pathfinder data. We report a total of 54 candidates with transferred momenta ranging from 0.2 to 230 μNs. We furthermore make a comparison of these candidates with models of micrometeoroid populations in the inner solar system, including those resulting from Jupiter-family comets (JFCs), Oort Cloud comets, Halley-type comets, and asteroids. We find that our measured population is consistent with a population dominated by JFCs, with some evidence for a smaller contribution from Halley-type comets, in agreement with consensus models of the zodiacal dust complex in the momentum range sampled by LISA Pathfinder.

Scale of Small Particle Population in Activated Sludge Flocs

The light scattering method is a valuable tool for accessing particle size and structure mainly due to fast and the nonintrusive nature of the measurement. The method is based on a scattered intensity pattern and depends on particle volume, particle morphology, the light wavelength and the scattering angle. The light scattering model, for particles characterised by a fractal structure, is enabled with the use of the Rayleigh-Gans-Debye theory under constrained assumptions. The range of validity of the Rayleigh-Gans-Debye is limited when primary particles constituting aggregate have a size close to the wavelength. In this work, a range of particle sizes was characterised in order to achieve a better understanding of the relationship between flocs size and its fractal dimension. Hence, the width of the power law regime is discussed. What is more, a specific fractal dimension value of activated sludge flocs was found for each of the analysed wastewater treatment plant, which suggests that the spatial structure of suspensions constituting the activated sludge is an individual characteristic of each treatment facility. It has been shown that activated sludge consists of microflocs from the range of 1–10 μm, which constitute approximately 90% of all the population.

Stable Hydrogen Generation from Copper/Titanium Oxide Heterogeneous Photocatalyst: A Confined Material Preparation Approach

Possessing exceptional properties, such as suitable band edges for redox reactions, environmental friendliness, low cost, availability, as well as long-term stability against photo- and chemical-corrosion, further modification of titanium oxide with heterogeneous structure has drawn considerable attention in today’s development of high efficiency photocatalysts toward efficient hydrogen generation. In contrast to precious noble metals, e.g. Pt and Au, earth abundant copper based materials have proven to be capable alternatives. Relevant researches mainly focused on the preparation of copper oxides modified titanium oxide with only very limited attention on metallic copper. The most widely used conventional preparation approach, wet-impregnation, has shown difficulties in achieving a fine dispersion for a high population of small particles. In the present work, we demonstrate a new synthesis strategy, layered-titanate mediated preparation for high efficiency copper-modified titanium oxide photocatalysts that exhibit a hydrogen generation efficiency excess that of copper-modified P25 titanium oxide prepared through wet-impregnation for over 40%.

Statistical physics-based model of mechanical degradation in lithium ion batteries

The article presents a statistical model of mechanical degradation in the negative electrode of lithium ion batteries. During battery operation, nano-cracks nucleate and grow caused by the impact of diffusion-induced stress during Li-ion intercalation. Particle agglomeration is another mechanical effect that contributes to morphological changes. The presented model employs a population balance formalism to describe the propagation of the particle density distribution function in the electrode. A set of kinetic and transport equations accounts for structure-transforming processes at the level of individual particles. These processes alter the particle density distribution function, and cause changes in battery performance. A parametric study reveals the population of small particles and the width of the initial particle size distribution (PSD) as the main parameters that determine changes in electrochemical performance and capacity fade. The model is applied to experimental data in order to isolate and quantify the impact of various degradation mechanisms.

The effect of magnetic equilibrium on auxiliary heating schemes and fast particle confinement in Wendelstein 7-X

The performance of the auxiliary heating systems ion cyclotron resonance heating and neutral beam injection is calculated in three different magnetic mirror configurations foreseen to be used in future experiments in the Wendelstein 7-X stellarator: low, standard and high mirror. This numerical work is implemented with the SCENIC code package, which is designed to model three-dimensional magnetic equilibria whilst retaining effects such as anisotropy and the influence of including a finite orbit width of the particles. The ability to simulate NBI deposition in three-dimensional equilibria, the implementation of the realistic beam injector geometry, and the modification of the SCENIC package to permit the investigation of the 3-ion species heating scheme, are recent developments. Using these modifications, an assessment of the advantages and disadvantages of these two fast-ion producing auxiliary heating systems is made in the three different magnetic mirror equilibria. For NBI heating, the high mirror configuration displays the best global confinement properties, resulting in a larger collisional power transfer to the background plasma. The standard mirror has the best particle confinement in the core region, but the worst towards the edge of the plasma. The low mirror has the largest lost power and thus the lowest total collisional power. For ICRH, the displacement of the RF-resonant surface significantly impacts the heating performance. Due to the large toroidal magnetic mirror in the high mirror equilibrium, resonant particles easily become trapped and cannot remain in resonance, generating only small energetic particle populations. Despite this, global confinement is still the strongest in this equilibrium. The low mirror is the only equilibrium to produce peaked on-axis collisional power deposition, with associated peaked on-axis fast ion pressure profiles. A highly energetic particle population is then produced but this results in larger lost power as this equilibrium is not sufficiently optimised for fast ion confinement. A comparison between the two heating methods concludes that NBI produces a smaller fraction of lost to input power, and a reduced sensitivity of the performance to variations of the toroidal magnetic mirror. The main limit of NBI which does not apply to ICRH is the production of highly energetic particle populations, with predictions of energetic particles of E ∼ 0.45 MeV.

Cassini UVIS solar occultations by Saturn’s F ring and the detection of collision-produced micron-sized dust

We present an analysis of eleven solar occultations by Saturn’s F ring observed by the Ultraviolet Imaging Spectrograph (UVIS) on the Cassini spacecraft. In four of the solar occultations we detect an unambiguous signal from diffracted sunlight that adds to the direct solar signal just before or after the occultations occur. The strongest detection was a 10% increase over the direct signal that was enabled by the accidental misalignment of the instrument’s pointing. We compare the UVIS data with images of the F ring obtained by the Cassini Imaging Science Subsystem (ISS) and find that in each instance of an unambiguous diffraction signature in the UVIS data, the ISS data shows that there was a recent disturbance in that region of the F ring. Similarly, the ISS images show a quiescent region of the F ring for all solar occultations in which no diffraction signature was detected. We therefore conclude that collisions in the F ring produce a population of small ring particles that can produce a detectable diffraction signal immediately interior or exterior to the F ring. The clearest example of this connection comes from the strong detection of diffracted light in the 2007 solar occultation, when the portion of the F ring that occulted the Sun had suffered a large collisional event, likely with S/2004 S 6, several months prior. This collision was observed in a series of ISS images (Murray et al., 2008).Our spectral analysis of the data shows no significant spectral features in the F ring, indicating that the particles must be at least 0.2 µm in radius. We apply a forward model of the solar occultations, accounting for the effects of diffracted light and the attenuated direct solar signal, to model the observed solar occultation light curves. These models constrain the optical depth, radial width, and particle size distribution of the F ring. We find that when the diffraction signature is present, we can best reproduce the occultation data using a particle population with an average effective particle size of less than 300 µm, while occultations without clear diffraction signals are best modeled using a population with an effective particle size larger than 400 µm.

Stirring Affects Starch Granule Morphology and the Functional Properties of Rice Flour

Stirring is widely used to process rice flour, but its influence on the flour's functional properties is generally ignored. Here, the effect of various treatments given to the flour prepared from three cultivars contrasting for their grain amylose content is investigated. The major effect of stirring is to disaggregate the starch granules, releasing a population of small particles which are readily degraded by endogenous amylase. The presence of the small particles increases the flour's solubility, swelling power, and peak viscosity, as well as the adhesive force and springiness of the retrograded gel. It also decreases the onset and peak gelatinization temperatures and the enthalpy of the flour, as well as the hardness of the retrograded gel. Stirring aids the gelatinization of rice flour and has a negative effect on the retrogradation of the rice flour gel.

Macromolecular crowding directs the motion of small molecules inside cells.

It is now well established that cell interiors are significantly crowded by macromolecules, which impede diffusion and enhance binding rates. However, it is not fully appreciated that levels of crowding are heterogeneous, and can vary substantially between subcellular regions. In this article, starting from a microscopic model, we derive coupled nonlinear partial differential equations for the concentrations of two populations of large and small spherical particles with steric volume exclusion. By performing an expansion in the ratio of the particle sizes, we find that the diffusion of a small particle in the presence of large particles obeys an advection–diffusion equation, with a reduced diffusion coefficient and a velocity directed towards less crowded regions. The interplay between advection and diffusion leads to behaviour that differs significantly from Brownian diffusion. We show that biologically plausible distributions of macromolecules can lead to highly non-Gaussian probability densities for the small particle position, including asymmetrical and multimodal densities. We confirm all our results using hard-sphere Brownian dynamics simulations.

Analysis of Alfvén eigenmode destabilization by energetic particles in Large Helical Device using a Landau-closure modelaaThis manuscript has been authored by UT-Battelle, LLC under contract no. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government and the publisher, by accepting the article for publication, acknowledge that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to

Energetic particle populations in nuclear fusion experiments can destabilize the Alfvén Eigenmodes through inverse Landau damping and couplings with gap modes in the shear Alfvén continua. We use the reduced MHD equations to describe the linear evolution of the poloidal flux and the toroidal component of the vorticity in a full 3D system, coupled with equations of density and parallel velocity moments for the energetic particles. We add the Landau damping and resonant destabilization effects using a closure relation. We apply the model to study the Alfvén mode stability in the inward-shifted configurations of the Large Helical Device (LHD), performing a parametric analysis of the energetic particle β () in a range of realistic values, the ratios of the energetic particle thermal/Alfvén velocities (), the magnetic Lundquist numbers (S) and the toroidal modes (n). The n = 1 and n = 2 TAEs are destabilized, although the n = 3 and n = 4 TAEs are weakly perturbed. The most unstable configurations are associated with the density gradients of energetic particles in the plasma core: the TAEs are destabilized, even for small energetic particle populations, if their thermal velocity is lower than 0.4 times the Alfvén velocity. The frequency range of MHD bursts measured in the LHD are 50–70 kHz for the n = 1 and 60–80 kHz for the n = 2 TAE, which is consistent with the model predictions.

Detection and characterization of circumstellar material with a WFIRST or EXO-C coronagraphic instrument: simulations and observational methods

The capabilities of a high (∼10−9 resel−1) contrast narrow-field coronagraphic instrument (CGI) on a space-based WFIRST-C or probe-class EXO-C/S mission are particularly and importantly germane to symbiotic studies of the systems of circumstellar material from which planets have emerged and interact with throughout their lifetimes. The small particle populations in “disks” of co-orbiting materials can trace the presence of planets through dynamical interactions that perturb the spatial distribution of light-scattering debris, which is detectable at visible wavelengths and resolvable with a WFIRST-C or EXO-S/C CGI. Herein, we (1) present the scientific case to study the formation, evolution, architectures, diversity, and properties of the material in the planet-hosting regions of nearby stars; (2) discuss how a CGI under current conception can uniquely inform and contribute to those investigations; (3) consider the applicability of CGI-anticipated performance for circumstellar debris system studies; (4) investigate, through WFIRST CGI image simulations, the anticipated interpretive fidelity and metrical results from specific representative zodiacal debris disk observations; (5) comment on specific observational modes and methods germane to and augmenting circumstellar debris system observations; and (6) present a case for augmenting future CGI instrumentation with the capability to obtain full linear-Stokes imaging polarimetery, which greatly benefits characterization of the material properties of circumstellar dust and exoplanet atmospheres (discussed in other studies).

Insight into Fast Nucleation and Growth of Zeolitic Imidazolate Framework-71 by In Situ Time-Resolved Light and X-ray Scattering Experiments

The current rather poor understanding of the mechanisms of crystallization of zeolitic imidazolate frameworks (ZIFs), an important subclass of porous metal organic framework (MOF) materials, greatly hampers rational synthesis of predicted ZIF phases/polymorphs and control of crystal size/shape. In this contribution, we present the results of in situ studies on a recently developed fast ZIF-71 nanocrystal synthesis from solution. By taking advantage of the combined use of time-resolved static and dynamic light scattering and stopped-flow synchrotron small-angle and wide-angle X-ray scattering, we were able to reveal the whole nanocrystal formation process: a population of small amorphous particles (termed clusters) first forms via coagulation, followed by the formation of a second population of bigger amorphous particles that grow via addition of significantly smaller “monomers”, the nature of which remains as yet unknown (clusters and/or smaller units). The latter particles transform into the periodic ZIF...

Detection and measurement of micrometeoroids with LISA Pathfinder

The Solar System contains a population of dust and small particles originating from asteroids, comets, and other bodies. These particles have been studied using a number of techniques ranging from in-situ satellite detectors to analysis of lunar microcraters to ground-based observations of zodiacal light. In this paper, we describe an approach for using the LISA Pathfinder (LPF) mission as an instrument to detect and characterize the dynamics of dust particles in the vicinity of Earth-Sun L1. Launching in late 2015, LPF is a dedicated technology demonstrator mission that will validate several key technologies for a future space-based gravitational-wave observatory. The primary science instrument aboard LPF is a precision accelerometer which we show will be capable of sensing discrete momentum impulses as small as $4\times 10^{-8}\,\textrm{N}\cdot\textrm{s}$. We then estimate the rate of such impulses resulting from impacts of micrometeoroids based on standard models of the micrometeoroid environment in the inner solar system. We find that LPF may detect dozens to hundreds of individual events corresponding to impacts of particles with masses $> 10^{-9}\,$g during LPF's roughly six-month science operations phase in a $5\times 10^5\,\textrm{km}$ by $8\times 10^5\,\textrm{km}$ Lissajous orbit around L1. In addition, we estimate the ability of LPF to characterize individual impacts by measuring quantities such as total momentum transferred, direction of impact, and location of impact on the spacecraft. Information on flux and direction provided by LPF may provide insight as to the nature and origin of the individual impact and help constrain models of the interplanetary dust complex in general. Additionally, this direct in-situ measurement of micrometeoroid impacts will be valuable to designers of future spacecraft targeting the environment around L1.