Predicting who responds to spinal manipulative therapy using a short-time frame methodology: Results from a 238-participant study.

BACKGROUND: Spinal manipulative therapy (SMT) is among the nonpharmacologic interventions that has been recommended in clinical guidelines for patients with low back pain, however, some patients appear to benefit substantially more from SMT than others. Several investigations have examined potential factors to modify patients' responses prior to SMT application. The objective of this study was to determine if the baseline prediction of SMT responders can be improved through the use of a restricted, non-pragmatic methodology, established variables of responder status, and newly developed physical measures observed to change with SMT. MATERIALS AND METHODS: We conducted a secondary analysis of a prior study that provided two applications of standardized SMT over a period of 1 week. After initial exploratory analysis, principal component analysis and optimal scaling analysis were used to reduce multicollinearity among predictors. A multiple logistic regression model was built using a forward Wald procedure to explore those baseline variables that could predict response status at 1-week reassessment. RESULTS: Two hundred and thirty-eight participants completed the 1-week reassessment (age 40.0± 11.8 years; 59.7% female). Response to treatment was predicted by a model containing the following 8 variables: height, gender, neck or upper back pain, pain frequency in the past 6 months, the STarT Back Tool, patients' expectations about medication and strengthening exercises, and extension status. Our model had a sensitivity of 72.2% (95% CI, 58.1-83.1), specificity of 84.2% (95% CI, 78.0-89.0), a positive likelihood ratio of 4.6 (CI, 3.2-6.7), a negative likelihood ratio of 0.3 (CI, 0.2-0.5), and area under ROC curve, 0.79. CONCLUSION: It is possible to predict response to treatment before application of SMT in low back pain patients. Our model may benefit both patients and clinicians by reducing the time needed to re-evaluate an initial trial of care.

Differential patient responses to spinal manipulative therapy and their relation to spinal degeneration and post-treatment changes in disc diffusion.

PURPOSE: Our prior study revealed that people with non-specific low back pain (LBP) who self-reported a > 30% improvement in disability after SMT demonstrated significant post-treatment improvements in spinal stiffness, dynamic muscle thickness and disc diffusion, while those not having self-reported improvement did not have these objective changes. The mechanism underlying this differential post-SMT response remains unknown. This exploratory secondary analysis aimed to determine whether persons with non-specific LBP who respond to spinal SMT have unique lumbar magnetic resonance imaging (MRI) findings compared to SMT non-responders. METHODS: Thirty-two participants with non-specific LBP received lumbar MRI before and after SMT on Day 1. Resulting images were assessed for facet degeneration, disc degeneration, Modic changes and apparent diffusion coefficient (ADC). SMT was provided again on Day 4 without imaging. SMT responders were classified as having a ≥ 30% reduction in their modified Oswestry disability index at Day 7. Baseline MRI findings between responders and non-responders were compared. The associations between SMT responder status and the presence/absence of post-SMT increases in ADC values of discs associated with painful/non-painful segments as determined by palpation were calculated. In this secondary analysis, a statistical trend was considered as a P value between 0.05 and 0.10. RESULTS: Although there was no significant between-group difference in all spinal degenerative features (e.g. Modic changes), SMT responders tended to have a lower prevalence of severely degenerated facets (P = 0.05) and higher baseline ADC values at the L4-5 disc when compared to SMT non-responders (P = 0.09). Post hoc analyses revealed that 180 patients per group should have been recruited to find significant between-group differences in the two features. SMT responders were also characterized by significant increases in post-SMT ADC values at discs associated with painful segments identified by palpation (P < 0.01). CONCLUSIONS: The current secondary analysis suggests that the spines of SMT responders appear to differ from non-responders with respect to degeneration changes in posterior joints and disc diffusion. Although this analysis was preliminary, it provides a new direction to investigate the mechanisms underlying SMT and the existence of discrete forms of treatment-specific LBP. These slides can be retrieved under Electronic Supplementary Material.

Does the application site of spinal manipulative therapy alter spinal tissues loading?

BACKGROUND CONTEXT: Previous studies found that the intervertebral disc (IVD) experiences the greatest loads during spinal manipulation therapy (SMT). PURPOSE: Based on that, this study aimed to determine if loads experienced by spinal tissues are significantly altered when the application site of SMT is changed. STUDY DESIGN: A biomechanical robotic serial dissection study. SAMPLE: Thirteen porcine cadaveric motion segments. OUTCOME MEASURES: Forces experienced by lumbar spinal tissues. METHODS: A servo-controlled linear actuator provided standardized 300 N SMT simulations to six different cutaneous locations of the porcine lumbar spine: L2-L3 and L3-L4 facet joints (FJ), L3 and L4 transverse processes (TVP), and the space between the FJs and the TVPs (BTW). Vertebral kinematics were tracked optically using indwelling bone pins; the motion segment was removed and mounted in a parallel robot equipped with a six-axis load cell. Movements of each SMT application at each site were replayed by the robot with the intact specimen and following the sequential removal of spinal ligaments, FJs and IVD. Forces induced by SMT were recorded, and specific axes were analyzed using linear mixed models. RESULTS: Analyses yielded a significant difference (p<.05) in spinal structures loads as a function of the application site. Spinal manipulative therapy application at the L3 vertebra caused vertebral movements and forces between L3 and L4 spinal segment in the opposite direction to when SMT was applied at L4 vertebra. Additionally, SMT applications over the soft tissue between adjacent vertebrae significantly decreased spinal structure loads. CONCLUSION: Applying SMT with a constant force at different spinal levels creates different relative kinetics of the spinal segments and load spinal tissues in significantly different magnitudes.

Influence of Spinal Manipulative Therapy Force Magnitude and Application Site on Spinal Tissue Loading: A Biomechanical Robotic Serial Dissection Study in Porcine Motion Segments.

OBJECTIVE: In order to define the relation between spinal manipulative therapy (SMT) input parameters and the distribution of load within spinal tissues, the aim of this study was to determine the influence of force magnitude and application site when SMT is applied to cadaveric spines. METHODS: In 10 porcine cadavers, a servo-controlled linear actuator motor provided a standardized SMT simulation using 3 different force magnitudes (100N, 300N, and 500N) to 2 different cutaneous locations: L3/L4 facet joint (FJ), and L4 transverse processes (TVP). Vertebral kinematics were tracked optically using indwelling bone pins, the motion segment removed and mounted in a parallel robot equipped with a 6-axis load cell. The kinematics of each SMT application were replicated robotically. Serial dissection of spinal structures was conducted to quantify loading characteristics of discrete spinal tissues. Forces experienced by the L3/L4 segment and spinal structures during SMT replication were recorded and analyzed. RESULTS: Spinal manipulative therapy force magnitude and application site parameters influenced spinal tissues loading. A significant main effect (P < .05) of force magnitude was observed on the loads experienced by the intact specimen and supra- and interspinous ligaments. The main effect of application site was also significant (P < .05), influencing the loading of the intact specimen and facet joints, capsules, and ligamentum flavum (P < .05). CONCLUSION: Spinal manipulative therapy input parameters of force magnitude and application site significantly influence the distribution of forces within spinal tissues. By controlling these SMT parameters, clinical outcomes may potentially be manipulated.

Room-Temperature Processing of TiOx Electron Transporting Layer for Perovskite Solar Cells.

In order to realize high-throughput roll-to-roll manufacturing of flexible perovskite solar cells, low-temperature processing of all device components must be realized. However, the most commonly used electron transporting layer in high-performance perovskite solar cells is based on TiO2 thin films processed at high temperature (>450 °C). Here, we demonstrate room temperature solution processing of the TiOx layer that performs as well as the high temperature TiO2 layer in perovskite solar cells, as evidenced by a champion solar cell efficiency of 16.3%. Using optical spectroscopy, electrical measurements, and X-ray diffraction, we show that the room-temperature processed TiOx is amorphous with organic residues, and yet its optical and electrical properties are on par with the high-temperature TiO2. Flexible perovskite solar cells that employ a room-temperature TiOx layer with a power conversion efficiency of 14.3% are demonstrated.

Quality of transurethral resection of bladder tumor procedure influenced a phase III trial comparing the effect of KLH and mitomycin C.

BACKGROUND: Retrospective analysis of Center effect of the multi-center trial conducted to compare Immucothel (KLH Immunotherapy drug product) with Mytomycin-C (MM) concluded that efficacy evaluation of the drug product may be impacted by physician's subjective performance of Transurethral resection of bladder tumor (TURBT). METHODS: A randomized trial was performed in 18 hospitals (clinical centers) and a total of 553 recruited, 283 patients under KLH arm and 270 patients under MM. An initial statistical analysis of efficacy comparisons between KLH and MM based on log-rank test performed for each center (hospital) showed 6 hospitals out of 18 hospitals a p-value of <0.05 and remaining 12 hospitals showed a p-values of >0.05. No association was observed between number of patients analysed and the associated p-values across hospitals. Final statistical analyses were carried out under each drug product using Kaplan-Meier survival analysis along with log-rank test after combining all eligible patients data for 6 hospital group and 12 hospital group. RESULTS: Median recurrence free survival (RFS) times (in weeks) showed statistical significance (p-value = 0.03) between two groups of hospitals under KLH arm, while similar median values showed no statistical significance (p-value = 0.05). CONCLUSION: Center effect with respect to median RFS values under KLH was more pronounced than under MM. Under the presence of such center effect, for reasons other than product related effects, concluding superiority of one drug product over another may create confounding bias conclusions in multi-center clinical trials. In the above cited clinical trial study, physician's prior experience on TURBT might have contributed to center effect in examining efficacies of KLH and MM. Similar observation was also noted in the literature on studies dealing with TURBT and in other clinical studies. TRIAL REGISTRATION: Data set used in this study is based on previously documented clinical trial in the literature: See (Lammers et al., J Clin Oncol 30:2273-9, 2012) and Acknowledgments.

Spinal Tissue Loading Created by Different Methods of Spinal Manipulative Therapy Application.

STUDY DESIGN: Comparative study using robotic replication of spinal manipulative therapy (SMT) vertebral kinematics together with serial dissection. OBJECTIVE: The aim of this study was to quantify loads created in cadaveric spinal tissues arising from three different forms of SMT application. SUMMARY OF BACKGROUND DATA: There exist many distinct methods by which to apply SMT. It is not known presently whether different forms of SMT application have different effects on spinal tissues. Should the method of SMT application modulate spinal tissue loading, quantifying this relation may help explain the varied outcomes of SMT in terms of effect and safety. METHODS: SMT was applied to the third lumbar vertebra in 12 porcine cadavers using three SMT techniques: a clinical device that applies forces through a hand-held instrument (INST), a manual technique of applying SMT clinically (MAN) and a research device that applies parameters of manual SMT through a servo-controlled linear actuator motor (SERVO). The resulting kinematics from each SMT application were tracked optically via indwelling bone pins. The L3/L4 segment was then removed, mounted in a parallel robot and the resulting kinematics from SMT replayed for each SMT application technique. Serial dissection of spinal structures was conducted to quantify loading characteristics of discrete spinal tissues. RESULTS: In terms of load magnitude, SMT application with MAN and SERVO created greater forces than INST in all conditions (P < 0.05). Additionally, MAN and SERVO created comparable posterior forces in the intact specimen, but MAN created greater posterior forces on IVD structures compared to SERVO (P < 0.05). CONCLUSION: Specific methods of SMT application create unique vertebral loading characteristics, which may help explain the varied outcomes of SMT in terms of effect and safety. LEVEL OF EVIDENCE: N/A.

A three-beam aerosol backscatter correlation lidar for wind profiling.

In this paper, the development of a three-beam aerosol backscatter correlation (ABC) lidar to measure wind characteristics for wake vortex and plume tracking applications is discussed. This is a direct detection elastic lidar that uses three laser transceivers, operating at 1030 nm wavelength with ~10 kHz pulse repetition frequency and nanosec class pulse widths, to directly obtain three components of wind velocities. By tracking the motion of aerosol structures along and between three near-parallel laser beams, three-component wind speed profiles along the field-of-view of laser beams are obtained. With three 8-inch transceiver modules, placed in a near-parallel configuration on a two-axis pan-tilt scanner, the lidar measures wind speeds up to 2 km away. Optical flow algorithms have been adapted to obtain the movement of aerosol structures between the beams. Aerosol density fluctuations are cross-correlated between successive scans to obtain the displacements of the aerosol features along the three axes. Using the range resolved elastic backscatter data from each laser beam, which is scanned over the volume of interest, a 3D map of aerosol density in a short time span is generated. The performance of the ABC wind lidar prototype, validated using sonic anemometer measurements, is discussed.

Tissue loading created during spinal manipulation in comparison to loading created by passive spinal movements.

Spinal manipulative therapy (SMT) creates health benefits for some while for others, no benefit or even adverse events. Understanding these differential responses is important to optimize patient care and safety. Toward this, characterizing how loads created by SMT relate to those created by typical motions is fundamental. Using robotic testing, it is now possible to make these comparisons to determine if SMT generates unique loading scenarios. In 12 porcine cadavers, SMT and passive motions were applied to the L3/L4 segment and the resulting kinematics tracked. The L3/L4 segment was removed, mounted in a parallel robot and kinematics of SMT and passive movements replayed robotically. The resulting forces experienced by L3/L4 were collected. Overall, SMT created both significantly greater and smaller loads compared to passive motions, with SMT generating greater anterioposterior peak force (the direction of force application) compared to all passive motions. In some comparisons, SMT did not create significantly different loads in the intact specimen, but did so in specific spinal tissues. Despite methodological differences between studies, SMT forces and loading rates fell below published injury values. Future studies are warranted to understand if loading scenarios unique to SMT confer its differential therapeutic effects.

Does experimental low back pain change posteroanterior lumbar spinal stiffness and trunk muscle activity? A randomized crossover study.

BACKGROUND: While some patients with low back pain demonstrate increased spinal stiffness that decreases as pain subsides, this observation is inconsistent. Currently, the relation between spinal stiffness and low back pain remains unclear. This study aimed to investigate the effects of experimental low back pain on temporal changes in posteroanterior spinal stiffness and concurrent trunk muscle activity. METHOD: In separate sessions five days apart, nine asymptomatic participants received equal volume injections of hypertonic or isotonic saline in random order into the L3-L5 interspinous ligaments. Pain intensity, spinal stiffness (global and terminal stiffness) at the L3 level, and the surface electromyographic activity of six trunk muscles were measured before, immediately after, and 25-minute after injections. These outcome measures under different saline conditions were compared by generalized estimating equations. FINDINGS: Compared to isotonic saline injections, hypertonic saline injections evoked significantly higher pain intensity (mean difference: 5.7/10), higher global (mean difference: 0.73N/mm) and terminal stiffness (mean difference: 0.58N/mm), and increased activity of four trunk muscles during indentation (P<0.05). Both spinal stiffness and trunk muscle activity returned to baseline levels as pain subsided. INTERPRETATION: While previous clinical research reported inconsistent findings regarding the association between spinal stiffness and low back pain, our study revealed that experimental pain caused temporary increases in spinal stiffness and concurrent trunk muscle co-contraction during indentation, which helps explain the temporal relation between spinal stiffness and low back pain observed in some clinical studies. Our results substantiate the role of spinal stiffness assessments in monitoring back pain progression.

Structural health monitoring (vibration) as a tool for identifying structural alterations of the lumbar spine: a twin control study.

Structural health monitoring (SHM) is an engineering technique used to identify mechanical abnormalities not readily apparent through other means. Recently, SHM has been adapted for use in biological systems, but its invasive nature limits its clinical application. As such, the purpose of this project was to determine if a non-invasive form of SHM could identify structural alterations in the spines of living human subjects. Lumbar spines of 10 twin pairs were visualized by magnetic resonance imaging then assessed by a blinded radiologist to determine whether twin pairs were structurally concordant or discordant. Vibration was then applied to each subject's spine and the resulting response recorded from sensors overlying lumbar spinous processes. The peak frequency, area under the curve and the root mean square were computed from the frequency response function of each sensor. Statistical analysis demonstrated that in twins whose structural appearance was discordant, peak frequency was significantly different between twin pairs while in concordant twins, no outcomes were significantly different. From these results, we conclude that structural changes within the spine can alter its vibration response. As such, further investigation of SHM to identify spinal abnormalities in larger human populations is warranted.

Quantification of loading in biomechanical testing: the influence of dissection sequence.

Sequential dissection is a technique used to investigate loads experienced by articular tissues. When the joint of interest is tested in an unconstrained manner, its kinematics change with each tissue removal. To address this limitation, sufficiently rigid robots are used to constrain joint kinematics. While this approach can quantify loads experienced by each tissue, it does not assure similar results when removal order is changed. Specifically, structure loading is assumed to be independent of removal order if the structure behaves linearly (i.e. principle of superposition applies), but dependent on removal order when response is affected by material and/or geometry nonlinearities and/or viscoelasticiy (e.g. biological tissues). Therefore, this experiment was conducted to evaluate if structure loading created through robotic testing is dependent on the order in which connectors are removed. Six identical models were 3D printed. Each model was composed of 2 rigid bodies and 3 connecting structures with nonlinear time-dependent behavior. To these models, pure rotations were applied about a predefined static center of rotation using a parallel robot. A unique dissection sequence was used for each of the six models and the same movements applied robotically after each dissection. When comparing the moments experienced by each structure between different removal sequences, a statistically significant difference (p<0.05) was observed. These results suggest that even in an optimized environment, the sequence in which nonlinear viscoelastic structures are removed influence model loading. These findings support prior work suggesting that tissue loads obtained from robotic testing are specific to removal order.

A non-randomized clinical trial to assess the impact of nonrigid, inelastic corsets on spine function in low back pain participants and asymptomatic controls.

BACKGROUND CONTEXT: Although previous studies suggest braces/corsets can reduce acute pain, no prior study has assessed back function after bracing with both self-reported and objective measures. Use of both self-reported and objective measures of spine function together may be important given evidence they assess unique aspects of function. PURPOSE: The aim was to assess both self-reported and objective measures of spinal function before, and after, use of a nonrigid, inelastic lumbar brace. STUDY DESIGN/SETTING: This was a non-randomized clinical trial. PATIENT SAMPLE: The sample included acute low back pain (LBP) participants and asymptomatic controls. OUTCOME MEASURES: Oswestry Disability Index (ODI), spinal stiffness, and muscle endurance were the outcome measures. METHODS: Three groups were studied: -LBP/-Brace (n=19), -LBP/+Brace (n=18), and +LBP/+Brace (n=17). Both groups of braced participants were instructed to wear the brace continually for 2 weeks with the exception of bedroom and bathroom activities. Before and after the 2-week period, three measures of spinal function were performed: spinal stiffness via motorized indentation of the L3 spinous process, a modified Sorensen test (timed lumbar extension against gravity), and the ODI. Repeated measures analyses of variance were conducted for all three outcomes. RESULTS: Among the groups, ODI scores decreased significantly for the +LBP/+Brace group (p<.001) compared with the other two groups. The +LBP/+Brace mean ODI score decreased 3.71 points (95% confidence interval [CI] 2.01-5.40) compared with the -LBP/-Brace group and decreased 3.48 points (95% CI 1.77-5.20) compared with the -LBP/+Brace group. Change scores for the Sorensen test were significantly increased in the +LBP/+Brace group (p=.037) compared with the -LBP/-Brace group (22.47s 95% CI 8.14-36.80). Spinal stiffness did not change significantly between groups. CONCLUSIONS: This study demonstrates that lumbar function assessed by self-reported and objective measures does not worsen when nonrigid, inelastic bracing is used for short periods of time for those with, or without, back pain. These data add to the existing literature that suggests short-term use of nonrigid, inelastic bracing for acute LBP does not decrease spinal function when measured separately with subjective or objective tools.

Do participants with low back pain who respond to spinal manipulative therapy differ biomechanically from nonresponders, untreated controls or asymptomatic controls?

STUDY DESIGN: Nonrandomized controlled study. OBJECTIVE: To determine whether patients with low back pain (LBP) who respond to spinal manipulative therapy (SMT) differ biomechanically from nonresponders, untreated controls or asymptomatic controls. SUMMARY OF BACKGROUND DATA: Some but not all patients with LBP report improvement in function after SMT. When compared with nonresponders, studies suggest that SMT responders demonstrate significant changes in spinal stiffness, muscle contraction, and disc diffusion. Unfortunately, the significance of these observations remains uncertain given methodological differences between studies including a lack of controls. METHODS: Participants with LBP and asymptomatic controls attended 3 sessions for 7 days. On sessions 1 and 2, participants with LBP received SMT (+LBP/+SMT, n = 32) whereas asymptomatic controls did not (-LBP/-SMT, n = 57). In these sessions, spinal stiffness and multifidus thickness ratios were obtained before and after SMT and on day 7. Apparent diffusion coefficients from lumbar discs were obtained from +LBP/+SMT participants before and after SMT on session 1 and from an LBP control group that did not receive SMT (+LBP/-SMT, n = 16). +LBP/+SMT participants were dichotomized as responders/nonresponders on the basis of self-reported disability on day 7. A repeated measures analysis of covariance was used to compare apparent diffusion coefficients among responders, nonresponders, and +LBP/-SMT subjects, as well as spinal stiffness or multifidus thickness ratio among responders, nonresponders, and -LBP/-SMT subjects. RESULTS: After the first SMT, SMT responders displayed statistically significant decreases in spinal stiffness and increases in multifidus thickness ratio sustained for more than 7 days; these findings were not observed in other groups. Similarly, only SMT responders displayed significant post-SMT improvement in apparent diffusion coefficients. CONCLUSION: Those reporting post-SMT improvement in disability demonstrated simultaneous changes between self-reported and objective measures of spinal function. This coherence did not exist for asymptomatic controls or no-treatment controls. These data imply that SMT impacts biomechanical characteristics within SMT responders not present in all patients with LBP. This work provides a foundation to investigate the heterogeneous nature of LBP, mechanisms underlying differential therapeutic response, and the biomechanical and imaging characteristics defining responders at baseline. LEVEL OF EVIDENCE: 3.

Watt-level short-length holmium-doped ZBLAN fiber lasers at 1.2 µm.

In-band core-pumped Ho3+-doped ZBLAN fiber lasers at the 1.2 µm region were investigated with different gain fiber lengths. A 2.4 W 1190 nm all-fiber laser with a slope efficiency of 42% was achieved by using a 10 cm long gain fiber pumped at a maximum available 1150 nm pump power of 5.9 W. A 1178 nm all-fiber laser was demonstrated with an output power of 350 mW and a slope efficiency of 6.5%. High Ho3+ doping in ZBLAN is shown to be effective in producing single-frequency fiber lasers and short-length fiber amplifiers immune from stimulated Brillouin scattering.

Cross-band relative absorption technique for the measurement of molecular mixing ratios.

We describe a new method for the measurement of molecular mixing ratios called Cross-Band Relative Absorption (CoBRA). The proposed method is based on relative measurements in different molecular bands referenced to a band of O2 with properly selected wavelength combinations providing high level of cancelation in temperature sensitivities. The CoBRA approach is particularly promising for satellite based remote sensing of molecular mixing ratios of the atmospheric trace gases. Very low temperature sensitivities and the potential of achieving close weighting function matching for the measurement and reference wavelengths are the main advantages of the method. The effectiveness of CoBRA approach is demonstrated for the retrieval of CO2 mixing ratios (XCO2) with application to the ASCENDS mission.

Within- and between-day reliability of spinal stiffness measurements obtained using a computer controlled mechanical indenter in individuals with and without low back pain.

Instrumented spinal stiffness measurements have shown high test-retest reliability. However, factors that may affect reliability have yet to be investigated. The objective of this study was to compare the: 1) within- and between-day reliability of a mechanical indentation device (MID) in measuring spinal stiffness, 2) measurement precision of averaging multiple measurements, and 3) reliability of stiffness measurements between individuals with and without low back pain (LBP). The spinal stiffness of 26 volunteers with and without LBP was measured 3 times by MID in each of two visits 1-4 days apart. Two stiffness measures were calculated from the resulting force-displacement data: global stiffness and terminal stiffness. Intraclass correlation coefficients (ICCs) were used to estimate reliability. Measurement precision was measured by minimal detectable changes, bias and 95% limits of agreement. Using the mean of three spinal stiffness measurements, the measurement precision was improved by 33.7% over a single measurement. Averaging three measurements, the within- and between-day reliability point estimates of both global and terminal stiffness were 0.99 and 0.98, respectively. The reliability estimates of spinal stiffness measurement using MID were not significantly altered by the participants' LBP status across all circumstances (95% confidence intervals overlapped). With our experimental protocol, averaging three spinal stiffness measurements using MID produces reliable stiffness measurements regardless of individuals' LBP status.

Eye-safe compact Raman light detection and ranging temperature profiler.

The vertical profile of atmospheric temperature is a principal state variable to study atmospheric stability. A lidar system, constructed using a 355 nm Nd:YAG laser transmitter, measures the temperature profile using the rotational Raman technique. In comparison with traditional Raman lidar, the major innovations are the use of a low peak power and high repetition rate laser to achieve eye-safe operation in a compact reliable instrument and the use of an angle tuning filter to select operating wavelengths. We demonstrate the capability of both nighttime and daytime measurements as a step toward a future stand-alone capability for routine measurements of important meteorological properties in the lower atmosphere.