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The NASA Double Asteroid Redirection Test (DART) mission performed a kinetic impact on asteroid Dimorphos, the satellite of the binary asteroid (65803) Didymos, at 23:14 UTC on 26 September 2022 as a planetary defence test1. DART was the first hypervelocity impact experiment on an asteroid at size and velocity scales relevant to planetary defence, intended to validate kinetic impact as a means of asteroid deflection. Here we report a determination of the momentum transferred to an asteroid by kinetic impact. On the basis of the change in the binary orbit period2, we find an instantaneous reduction in Dimorphos’s along-track orbital velocity component of 2.70 ± 0.10 mm s−1, indicating enhanced momentum transfer due to recoil from ejecta streams produced by the impact3,4. For a Dimorphos bulk density range of 1,500 to 3,300 kg m−3, we find that the expected value of the momentum enhancement factor, β, ranges between 2.2 and 4.9, depending on the mass of Dimorphos. If Dimorphos and Didymos are assumed to have equal densities of 2,400 kg m−3, β=3.61−0.25+0.19(1σ). These βvalues indicate that substantially more momentum was transferred to Dimorphos from the escaping impact ejecta than was incident with DART. Therefore, the DART kinetic impact was highly effective in deflecting the asteroid Dimorphos.

Although no known asteroid poses a threat to Earth for at least the next century, the catalogue of near-Earth asteroids is incomplete for objects whose impacts would produce regional devastation1,2. Several approaches have been proposed to potentially prevent an asteroid impact with Earth by deflecting or disrupting an asteroid1–3. A test of kinetic impact technology was identified as the highest-priority space mission related to asteroid mitigation1. NASA’s Double Asteroid Redirection Test (DART) mission is a full-scale test of kinetic impact technology. The mission’s target asteroid was Dimorphos, the secondary member of the S-type binary near-Earth asteroid (65803) Didymos. This binary asteroid system was chosen to enable ground-based telescopes to quantify the asteroid deflection caused by the impact of the DART spacecraft4. Although past missions have utilized impactors to investigate the properties of small bodies5,6, those earlier missions were not intended to deflect their targets and did not achieve measurable deflections. Here we report the DART spacecraft’s autonomous kinetic impact into Dimorphos and reconstruct the impact event, including the timeline leading to impact, the location and nature of the DART impact site, and the size and shape of Dimorphos. The successful impact of the DART spacecraft with Dimorphos and the resulting change in the orbit of Dimorphos7demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if necessary.

The Double Asteroid Redirection Test (DART) spacecraft successfully performed the first test of a kinetic impactor for asteroid deflection by impacting Dimorphos, the secondary of near-Earth binary asteroid (65803) Didymos, and changing the orbital period of Dimorphos. A change in orbital period of approximately 7 min was expected if the incident momentum from the DART spacecraft was directly transferred to the asteroid target in a perfectly inelastic collision1, but studies of the probable impact conditions and asteroid properties indicated that a considerable momentum enhancement (β) was possible2,3. In the years before impact, we used lightcurve observations to accurately determine the pre-impact orbit parameters of Dimorphos with respect to Didymos4–6. Here we report the change in the orbital period of Dimorphos as a result of the DART kinetic impact to be −33.0 ± 1.0 (3σ) min. Using new Earth-based lightcurve and radar observations, two independent approaches determined identical values for the change in the orbital period. This large orbit period change suggests that ejecta contributed a substantial amount of momentum to the asteroid beyond what the DART spacecraft carried.

Developing a crystallization model that accurately predicts crystal growth and nucleation has been an important topic in the pharmaceutical industry for the past few decades. Particularly, as the pharmaceutical industry shifts toward continuous manufacturing, modeling will both reduce the workload for experimental optimization and allow for the development of model-based control systems that yield more consistent quality output. In this work, a unique approach for modeling size-dependent growth was applied to a set of batch cooling crystallizations. The cooling crystallization of carbamazepine (CBZ) in ethanol was monitored for solute concentration measurement by in-line Raman spectroscopy as well as for seed and product crystal size distribution (CSD) measurement by off-line laser diffraction. Based on these data, modeling was performed with MATLAB software using a combined quadrature method of moments and a method of characteristics technique in conjunction with a modified Mydlarz and Jones (MJ3) expression for size-dependent growth. This work expands upon our past work on modeling the cooling crystallization of CBZ by evaluating the effect of variable seed CSD on crystal growth rates as well as the accuracy of the model-predicted product CSD. Using the MJ3 size-dependent growth expression, variation in seed CSD resulted in high prediction errors for product CSD especially for the D10 value [root-mean-square error (RMSE) = 29.8%]. The error was reduced by varying the size-dependent growth parameters as a function of the seed CSD (RMSE = 7.4%). This new technique provided a better understanding of how the overall CSD affects crystal growth rates. The improved model may reduce the time needed to optimize experiments and provide better control of the variation of the CSD of the system.

We performed orthogonal technology comparisons of concurrent peripheral blood and biopsy tissue samples from 69 kidney transplant recipients who underwent comprehensive algorithm‐driven clinical phenotyping. The sample cohort included patients with normal protocol biopsies and stable transplant (sTx) function (n = 25), subclinical acute rejection (subAR, n = 23), and clinical acute rejection (cAR, n = 21). Comparisons between microarray and RNAsequencing (RNA‐seq) signatures were performed and demonstrated a strong correlation between the blood and tissue compartments for both technology platforms. A number of shared differentially expressed genes and pathways between subARand cARin both platforms strongly suggest that these two clinical phenotypes form a continuum of alloimmune activation. SubARis associated with fewer or less expressed genes than cARin blood, whereas in biopsy tissues, this clinical phenotype demonstrates a more robust molecular signature for both platforms. The discovery work done in this study confirms a clear ability to detect gene expression profiles for sTx, subAR,and cARin both blood and biopsy tissue, yielding equivalent predictive performance that is agnostic to both technology and platform. Our data also provide strong biological insights into the molecular mechanisms underlying these signatures, underscoring their logistical potential as molecular diagnostics to improve clinical outcomes following kidney transplantation. Using orthogonal microarray and next‐generation sequencing technologies, the authors demonstrate the ability to discover and internally validate gene expression profiles for two clinical phenotypes.

We performed orthogonal technology comparisons of concurrent peripheral blood and biopsy tissue samples from 69 kidney transplant recipients who underwent comprehensive algorithm-driven clinical phenotyping. The sample cohort included patients with normal protocol biopsies and stable transplant (sTx) function (n = 25), subclinical acute rejection (subAR, n = 23), and clinical acute rejection (cAR, n = 21). Comparisons between microarray and RNA sequencing (RNA-seq) signatures were performed and demonstrated a strong correlation between the blood and tissue compartments for both technology platforms. A number of shared differentially expressed genes and pathways between subAR and cAR in both platforms strongly suggest that these two clinical phenotypes form a continuum of alloimmune activation. SubAR is associated with fewer or less expressed genes than cAR in blood, whereas in biopsy tissues, this clinical phenotype demonstrates a more robust molecular signature for both platforms. The discovery work done in this study confirms a clear ability to detect gene expression profiles for sTx, subAR, and cAR in both blood and biopsy tissue, yielding equivalent predictive performance that is agnostic to both technology and platform. Our data also provide strong biological insights into the molecular mechanisms underlying these signatures, underscoring their logistical potential as molecular diagnostics to improve clinical outcomes following kidney transplantation.

An unbalanced microbiome may lead to disease by creating aberrant immune responses. A recent association of cellular rejection with the development of interstitial fibrosis and tubular atrophy (IFTA) suggests the role of immune-mediated tissue injury. We hypothesized that developing IFTA correlates with altered urinary tract microbiomes (UMBs). UMBs at two serial time points, 1 and 6–8 months posttransplant, were assessed by 16S microbial ribosomal gene sequencing in 25 patients developing biopsy-proven IFTA compared to 23 transplant patients with normal biopsies and excellent function (TX) and 20 healthy nontransplant controls (HC). Streptococcus, the dominant genera in HC males, was lower in IFTA and TX males at 1 month compared to HCs. At 6–8 months, Streptococcuswas further decreased in IFTA males, but normalized in TX. IFTA males and females had increases in number of genera per sample at 6–8 months. UMB composition varied substantially between individuals in all groups. Despite the wide variation in UMBs between individuals, IFTA was associated with a loss in dominant resident urinary microbes in males, and a parallel increase in nonresident, pathogenic bacteria in males and females. UMB changes may contribute to IFTA development by alteration of the host immune response.

An unbalanced microbiome may lead to disease by creating aberrant immune responses. A recent association of cellular rejection with the development of interstitial fibrosis and tubular atrophy (IFTA) suggests the role of immune‐mediated tissue injury. We hypothesized that developing IFTAcorrelates with altered urinary tract microbiomes (UMBs). UMBs at two serial time points, 1 and 6–8 months posttransplant, were assessed by 16S microbial ribosomal gene sequencing in 25 patients developing biopsy‐proven IFTAcompared to 23 transplant patients with normal biopsies and excellent function (TX) and 20 healthy nontransplant controls (HC). Streptococcus, the dominant genera in HCmales, was lower in IFTAand TXmales at 1 month compared to HCs. At 6–8 months, Streptococcuswas further decreased in IFTAmales, but normalized in TX. IFTAmales and females had increases in number of genera per sample at 6–8 months. UMBcomposition varied substantially between individuals in all groups. Despite the wide variation in UMBs between individuals, IFTAwas associated with a loss in dominant resident urinary microbes in males, and a parallel increase in nonresident, pathogenic bacteria in males and females. UMBchanges may contribute to IFTAdevelopment by alteration of the host immune response. The authors assess urinary microbiomes at 1 and 6–8 months posttransplant in 25 patients who developed biopsy‐proven interstitial fibrosis and tubular atrophy (IFTA), 23 transplant patients with normal biopsies and excellent function, and 20 healthy controls, and find an association of the development of IFTA with a loss in dominant resident urinary microbes in males, and a parallel increase in nonresident, pathogenic bacteria in males and females.

An interpolation method is described for range measurements of high precision altimetry with repeating intensity modulated continuous wave (IM-CW) lidar waveforms using binary phase shift keying (BPSK), where the range profile is determined by means of a cross-correlation between the digital form of the transmitted signal and the digitized return signal collected by the lidar receiver. This method uses reordering of the array elements in the frequency domain to convert a repeating synthetic pulse signal to single highly interpolated pulse. This is then enhanced further using Richardson–Lucy deconvolution to greatly enhance the resolution of the pulse. We show the sampling resolution and pulse width can be enhanced by about two orders of magnitude using the signal processing algorithms presented, thus breaking the fundamental resolution limit for BPSK modulation of a particular bandwidth and bit rate. We demonstrate the usefulness of this technique for determining cloud and tree canopy thicknesses far beyond this fundamental limit in a lidar not designed for this purpose.

An interpolation method is described for range measurements of high precision and altimetry using repeating intensity-modulated continuous wave (IM-CW) lidar waveforms, where the range is determined by means of a cross-correlation between the digital form of the transmitted signal and the digitized return signal collected by the lidar receiver. This method uses reordering of the array elements in the frequency domain to convert a repeating synthetic pulse signal to single highly interpolated pulse. The computation of this processing is marginally greater than the correlation itself, as it only involves reordering of the correlation in the frequency domain, which makes it possible to implement this in a real time application. It is shown through theoretical arguments and flight-testing that this is a viable method for high-speed interpolated range measurements. Standard deviation is 0.75 m over water with only 350 mw of transmitted power at 2600 m.

To identify the impact of the American Society of Anesthesiologists (ASA) physical status on postoperative length of stay (LOS) and to document the cost due to LOS after surgical management of the 8 most common lower extremity and 2 most common upper extremity isolated orthopaedic fractures.

To review homeless patients with orthopaedic trauma injuries and examine their emergency room (ER) usage, follow-up rates, and complication rates.

The focus of this study is to model and validate the performance of intensity-modulated continuous-wave (IM-CW) CO_2 laser absorption spectrometer (LAS) systems and their CO_2 column measurements from airborne and satellite platforms. The model accounts for all fundamental physics of the instruments and their related CO_2 measurement environments, and the modeling results are presented statistically from simulation ensembles that include noise sources and uncertainties related to the LAS instruments and the measurement environments. The characteristics of simulated LAS systems are based on existing technologies and their implementation in existing systems. The modeled instruments are specifically assumed to be IM-CW LAS systems such as the Exelis’ airborne multifunctional fiber laser lidar (MFLL) operating in the 1.57 μm CO_2 absorption band. Atmospheric effects due to variations in CO_2, solar radiation, and thin clouds, are also included in the model. Model results are shown to agree well with LAS atmospheric CO_2 measurement performance. For example, the relative bias errors of both MFLL simulated and measured CO_2 differential optical depths were found to agree to within a few tenths of a percent when compared to the in situ observations from the flight of 3 August 2011 over Railroad Valley (RRV), Nevada, during the summer 2011 flight campaign. In addition, the horizontal variations in the model CO_2 differential optical depths were also found to be consistent with those from MFLL measurements. In general, the modeled and measured signal-to-noise ratios (SNRs) of the CO_2 column differential optical depths (τ_d) agreed to within about 30%. Model simulations of a spaceborne IM-CW LAS system in a 390 km dawn/dusk orbit for CO_2 column measurements showed that with a total of 42 W of transmitted power for one offline and two different sideline channels (placed at different locations on the side of the CO_2 absorption line), the accuracy of the τ_d measurements for surfaces similar to the playa of RRV, Nevada, will be better than 0.1% for 10 s averages. For other types of surfaces such as low-reflectivity snow and ice surfaces, the precision and bias errors will be within 0.23% and 0.1%, respectively. Including thin clouds with optical depths up to 1, the SNR of the τ_d measurements with 0.1 s integration period for surfaces similar to the playa of RRV, Nevada, will be greater than 94 and 65 for sideline positions placed +3 and +10  pm, respectively, from the CO_2 line center at 1571.112 nm. The CO_2 column bias errors introduced by the thin clouds are ≤0.1% for cloud optical depth ≤0.4, but they could reach ∼0.5% for more optically thick clouds with optical depths up to 1. When the cloud and surface altitudes and scattering amplitudes are obtained from matched filter analysis, the cloud bias errors can be further reduced. These results indicate that the IM-CW LAS instrument approach when implemented in a dawn/dusk orbit can make accurate CO_2 column measurements from space with preferential weighting across the mid to lower troposphere in support of a future ASCENDS mission.

The 2007 National Research Council (NRC) Decadal Survey on Earth Science and Applications from Space recommended Active Sensing of CO_2 Emissions over Nights, Days, and Seasons (ASCENDS) as a midterm, Tier II, NASA space mission. ITT Exelis, formerly ITT Corp., and NASA Langley Research Center have been working together since 2004 to develop and demonstrate a prototype laser absorption spectrometer for making high-precision, column CO_2 mixing ratio measurements needed for the ASCENDS mission. This instrument, called the multifunctional fiber laser lidar (MFLL), operates in an intensity-modulated, continuous wave mode in the 1.57 μm CO_2 absorption band. Flight experiments have been conducted with the MFLL on a Lear-25, UC-12, and DC-8 aircraft over a variety of different surfaces and under a wide range of atmospheric conditions. Very high-precision CO_2 column measurements resulting from high signal-to-noise ratio (>1300) column optical depth (OD) measurements for a 10 s (∼1  km) averaging interval have been achieved. In situ measurements of atmospheric CO_2 profiles were used to derive the expected CO_2 column values, and when compared to the MFLL measurements over desert and vegetated surfaces, the MFLL measurements were found to agree with the in situ-derived CO_2 columns to within an average of 0.17% or ∼0.65  ppmv with a standard deviation of 0.44% or ∼1.7  ppmv. Initial results demonstrating ranging capability using a swept modulation technique are also presented.

Ninety-five specimens of 14 freshwater fish species from small streams in the Kuala Terengganu district and the Lake Kenyir Reservoir, Malaysia, were surveyed for coccidian infections. Six fish species proved to be infected with apicomplexans belonging to the genus Goussia. In all of these fishes Goussiaspecies were found in unsporulated and semisporulated stages. Oöcysts of four species inhabiting the intestinal epithelium became sporulated in tap-water within 24 hours. In two fish species sporulation failed and only unsporulated oöcysts were recorded in the intestine. Three of the intestinal species finishing sporulation proved to be new to science and were described as Goussia malayensisn. sp., G. bettaen. sp. and G. pogonognathin. sp. from Apocheilus panchax, Betta splendensand Hemirhamphodon pogonognatus, respectively. The fourth species, found in Trichogaster pectoralis, was identified as G. trichogasteriSzékely & Molnár, 1992, a species known from aquarium-cultured T. trichopterus.

The development of mobile standards has been a key factor in the widespread success and take-up of second generation (2G) cellular systems. Well though through standards, including roaming aspects, have enabled operators, using equipment from different manufacturers, to create global mobile networks, which allow users to roam seamlessly and obtain largely the same services wherever they happen to be. Third generation (3G) standards have built on the success of 2G and have increased the global awareness and applicability. In this light, this paper discusses the background for mobile standards and the factors that are influencing their ongoing development for third generation and beyond.

Knowing where licence and option leads come from can optimize the productivity in university technology transfer offices. This article presents the sources of over 1,100 leads for licences and options from six different institutions: the University of Florida; the Massachusetts Institute of Technology; Oak Ridge National Laboratory; the Oregon Health Sciences University; Tulane University; and the University of Utah. Data from each of the six offices confirm the authors’ suspicions that the majority of the leads come from inventors. The methodology used to gather the data is also described.

Knowing where licence and option leads come from can optimize the productivity in university technology transfer offices. This article presents the sources of over 1,100 leads for licences and options from six different institutions: the University of Florida; the Massachusetts Institute of Technology; Oak Ridge National Laboratory; the Oregon Health Sciences University; Tulane University; and the University of Utah. Data from each of the six offices confirm the authors' suspicions that the majority of the leads come from inventors. The methodology used to gather the data is also described.

The objective of this research was to improve upon current models used to predict the transport of nonsorptive solutes in the subsurface environment. We surveyed previous modeling efforts, including the familiar convection and dispersion equations, the micropore-macropore model, and the mobile-immobile zone model. The proposed model is a modification of an existing mobile-immobile zone model, which includes theoretical relationships useful in relating the process variables to each other. We verified some of these relationships with results of experimental studies in which tritiated water was used as a tracer in columns packed with selected sorbents. In addition, the model was used to successfully predict the results of other experiments in which the flow rate and column height were changed.

The separation of haemopoietic bone-marrow cells by centrifugation through discontinuous density gradients of Percoll is described. This method was used to prepare fractions enriched in erythroblasts, myeloid blast cells or reticulocytes from bone marrow of anaemic and non-anaemic rabbits, from the marrow of other anaemic laboratory animals and from human samples. It is a simple, rapid, reproducible and inexpensive technique that can be readily adapted to suit individual requirements. Secondly, a convenient method is presented for the separation of large quantities of bone-marrow cells into fractions enriched in erythroblasts at different stages of maturation, by velocity sedimentation through a linear gradient of 1-2% sucrose at unit gravity. In vitro, erythroblasts adhere together strongly via a mechanism almost certainly involving a beta-galactoside-specific surface lectin termed erythroid developmental agglutinin. Since the efficiency of cell-separation techniques depends heavily on the maintenance of a single cell suspension in which each unit can move independently, the presence of an adhesive molecule at the cell surface is of considerable significance. The effect of washing the marrow with a lactose-containing medium, which has been shown to remove the agglutinin, was therefore investigated in relation to both methods. The separation on Percoll gradients is considerably enhanced by this treatment. In addition, the unit-gravity sedimentation gradient can be loaded with 5-10 times more cells after lactose extraction in comparison with intact marrow. Although enrichment is less, a useful fractionation according to maturation is still obtained.

1. The net flux of Na from the lumen to the blood side of isolated sheep rumen epithelium was reduced to zero in the third 30 min period after treatment with ouabain. 2. The net flux of K from blood to lumen side of the epithelium was reduced from 0–34 to 0–13 mumole/cm2. hr in the third 30 min period after ouabain treatment. 3. The net flux of Cl from lumen to blood side of the epithelium was reduced from 1–4 to 0–72 mumole/cm2. hr in the third 30 min period after ouabain treatment. 4. The results support the existence of a Cl pump independent of Na transport and also a K pump in sheep rumen epithelium.

1. The effect on renal function of 1 M solutions of LiCl, NaCl, KCl, RbCl and CsCl and 3 M‐NaCl infused close‐arterially to the kidney for 10 min at 0–7ml./min has been studied in nine experiments on four unilaterally nephrectomized sheep. The levels of flow, electrolyte concentration and electrolyte excretion in the urine were measured before, during and for 50 min after the infusions. 2. The infusion of 1‐M‐NaCl produced little change in urine flow and composition whereas 3 M‐NaCl resulted in relatively small increases in urine flow and sodium excretion. 3. The infusion of lithium, potassium, rubidium and caesium resulted in marked increases in urine flow, urinary sodium concentration and excretion, urinary potassium excretion and osmolal clearance while the urinary potassium concentration decreased. 4. Changes in urine flow and urinary pH during the infusions of all the alkali ions except sodium were consistent with increased urinary bicarbonate excretion. 5. The osmolal clearance was increased by the infusion of lithium, potassium, rubidium and caesium, but equivalent increases in the rate of solutefree water reabsorption did not occur. 6. The infusion of caesium resulted in a depression of the glomerular filtration rate (G.F.R.) which was not observed when the other alkali ions were infused. 7. The effects of lithium, potassium and rubidium on urine flow and composition were rapid in onset and the residual effects on these ions, on cessation of infusion, were relatively short. The effects on caesium were slow in onset and prolonged in duration. 8. It was concluded that lithium, potassium, rubidium, and caesium altered urine flow and electrolyte excretion by acting upon common mechanisms which were predominantly intra‐renal and located in the proximal segment of the nephron.

1. The net fluxes of sodium and chloride from the lumen to the blood side of isolated sheep rumen epithelium were reduced by treatment of both sides of the epithelium with acetazolamide. 2. The changes in the net fluxes of sodium and chloride were significantly correlated and showed recovery after removal of acetazolamide. 3. The net flux of potassium from blood to lumen side of the epithelim was not affected by treatment with acetazolamide. 4. It is suggested that acetazolamide blocks coupled sodium and chloride transport which may be mediated through 'low‐activity' carbonic anhydrase enzymes.

The effects of copper on the development ofCrassostrea gigas embryos were determined with a 48-hr static bioassay. In filtered, sterilized seawater from Bodega Bay, California, the LC100 was 20µg Cu/L, and the LC50 was 12µg Cu/L. Destruction of the naturally occurring dissolved organic material in the culture water by UV oxidation decreased embryo survival at 10µg Cu/L.

Summary.When [3H]progesterone is infused intravenously into ewes, blood 20α-dihydroprogesterone (20α-diHP) becomes labelled and the changes in [3H]20α-diHP activity with time are clearly related to that of [3H]progesterone. Concentrations of 20α-diHP in blood have now been estimated for these experiments. During the infusion, the specific radioactivity of 20α-diHP at steady state was only 53% of the specific radioactivity of progesterone, indicating that 20α-diHP was produced other than by C-20 reduction of secreted progesterone. The change in blood concentration of 20α-diHP during pregnancy in ewes suggests that the placenta is its source.[3H]20α-dihydroprogesterone was infused into pregnant ewes and the specific radioactivity of 20α-diHP measured during and after infusion. Together with information from earlier experiments when [3H]progesterone was infused, there is now sufficient data to estimate, without constraint, the parameters of a four-pool model describing the distribution and metabolism of progesterone and 20α-dyhydro-progesterone in sheep.

Abstract: Recent work by Wan and McLean has shown that all quantum measurements may be reduced to local position measurements. Using an array of particle detectors as the measuring apparatus we show how a model employing superselection rules and unitary evolution leads to a single detector triggering in each act of measurement. We also present an explicit model of particle detection as a unitary ionization process producing a single ion in the detector, subsequent amplification of which to the visible can be described adequately in classical terms.

The thermal decomposition of disodium propan-2-one-1,3-disulphonate (NaO3S.CH2.CO.CH2.SO3Na) in atmospheres of both oxygen and nitrogen proceded by a complete molecular disruption with sodium sulphate or mixtures of sodium sulphate and sodium carbonate as the final residues. No organic compounds were detected in the volatile products.

An endogenous β-galactoside-specific lectin has previously been isolated from rabbit bone marrow. The quantification of extracted lectin now indicates that approximately 75% of the lectin is intracellular in marrow. Indirect immunofluorescence studies show the extracellular lectin is associated with the erythroblast cell surface and is also found in some acellular areas of the marrow stroma. At enucleation, lectin surrounds the extruded nucleus while some residual lectin is observed in the cytoplasm of circulating reticulocytes and erythrocytes.