Effectiveness of psychological skills training for police personnel: a meta-analysis.

There has been an increasing interest in primary prevention programmes developed to improve police officers' mental health. This meta-analysis synthesised the existing findings on psychological skills training for police personnel including resilience training and mindfulness-based training. Particularly, this study systematically assessed the effectiveness of training programmes on mental health outcomes including resilience, depression, anxiety and perceived stress. A comprehensive search of EBSCO, ProQuest and Web of Science was conducted for studies written in English from 1999 to 2022. Two independent researchers screened 5604 studies. Eligible studies are intervention studies with controlled trials that involved training programmes to improve participants' mental health and reported at least one of the following outcomes: resilience, depression, anxiety and perceived stress. The meta-analysis estimated standardised mean differences (SMDs) for each of the four outcomes. A total of 12 studies, involving 2298 police personnel from 8 countries, met the criteria for inclusion and quality assessment. The training programmes of the eligible studies varied in training approaches, duration, total sessions and follow-up periods. The results suggest that training programmes have a statistically significant moderate effect on depression (SMD=-0.47, 95% CI=-0.73 to -0.22) and anxiety (SMD=-0.40, 95% CI=-0.73 to -0.06), while the effects on resilience (SMD=1.03, 95% CI=-0.36 to 2.41) and perceived stress (SMD=-1.03, 95% CI=-2.15 to 0.08) are not statistically significant. This study highlights the role of primary prevention approaches in supporting officers' mental health by showing that training programmes are effective in mitigating the risk of depression and anxiety.

Police stops to reduce crime: A systematic review and meta-analysis.

Background: Police-initiated pedestrian stops have been one of the most widely used crime prevention tactics in modern policing. Proponents have long considered police stops to be an indispensable component of crime prevention efforts, with many holding them responsible for the significant reductions in violent crime observed across major US cities in recent decades. Critics, however, have taken issue with the overuse of pedestrian stops, linking them to worsening mental and physical health, attitudes toward the police, and elevated delinquent behavior for individuals directly subject to them. To date, there has been no systematic review or meta-analysis on the effects of these interventions on crime and individual-level outcomes. Objectives: To synthesize the existing evaluation research regarding the impact of police-initiated pedestrian stops on crime and disorder, mental and physical health, individual attitudes toward the police, self-reported crime/delinquency, violence in police-citizen encounters, and police misbehavior. Search Methods: We used the Global Policing Database, a repository of all experimental and quasi-experimental evaluations of policing interventions conducted since 1950, to search for published and unpublished evaluations of pedestrian stop interventions through December of 2019. This overarching search was supplemented by additional searches of academic databases, gray literature sources, and correspondence with subject-matter experts to capture eligible studies through December 2021. Selection Criteria: Eligibility was limited to studies that included a treatment group of people or places experiencing pedestrian stops and a control group of people or places not experiencing pedestrian stops (or experiencing a lower dosage of pedestrian stops). Studies were required to use an experimental or quasi-experimental design and evaluate the intervention using an outcome of area-level crime and disorder, mental or physical health, individual or community-level attitudes toward the police, or self-reported crime/delinquency. Data Collection and Analysis: We adopted standard methodological procedures expected by the Campbell Collaboration. Eligible studies were grouped by conceptually similar outcomes and then analyzed separately using random effects models with restricted maximum likelihood estimation. Treatment effects were represented using relative incident rate ratios, odds ratios, and Hedges' g effect sizes, depending on the unit of analysis and outcome measure. We also conducted sensitivity analyses for several outcome measures using robust variance estimation, with standard errors clustered by each unique study/sample. Risk of bias was assessed using items adapted from the Cochrane randomized and non-randomized risk of bias tools. Results: Our systematic search strategies identified 40 eligible studies corresponding to 58 effect sizes across six outcome groupings, representing 90,904 people and 20,876 places. Police-initiated pedestrian stop interventions were associated with a statistically significant 13% (95% confidence interval [CI]: -16%, -9%, p < 0.001) reduction in crime for treatment areas relative to control areas. These interventions also led to a diffusion of crime control benefits, with a statistically significant 7% (95% CI: -9%, -4%, p < 0.001) reduction in crime for treatment displacement areas relative to control areas. However, pedestrian stops were also associated with a broad range of negative individual-level effects. Individuals experiencing police stops were associated with a statistically significant 46% (95% CI: 24%, 72%, p < 0.001) increase in the odds of a mental health issue and a 36% (95% CI: 14%, 62%, p < 0.001) increase in the odds of a physical health issue, relative to control. Individuals experiencing police stops also reported significantly more negative attitudes toward the police (g = -0.38, 95% CI: -0.59, -0.17, p < 0.001) and significantly higher levels of self-reported crime/delinquency (g = 0.30, 95% CI: 0.12, 0.48, p < 0.001), equating to changes of 18.6% and 15%, respectively. No eligible studies were identified measuring violence in police-citizen encounters or officer misbehavior. While eligible studies were often considered to be at moderate to high risk of bias toward control groups, no significant differences based on methodological rigor were observed. Moderator analyses also indicated that the negative individual-level effects of pedestrian stops may be more pronounced for youth, and that significant differences in effect sizes may exist between US and European studies. However, these moderator analyses were limited by a small number of studies in each comparison, and we were unable to compare the effects of police stops across racial groupings. Authors' Conclusions: While our findings point to favorable effects of pedestrian stop interventions on place-based crime and displacement outcomes, evidence of negative individual-level effects makes it difficult to recommend the use of these tactics over alternative policing interventions. Recent systematic reviews of hot spots policing and problem-oriented policing approaches indicate a more robust evidence-base and generally larger crime reduction effects than those presented here, often without the associated backfire effects on individual health, attitudes, and behavior. Future research should examine whether police agencies can mitigate the negative effects of pedestrian stops through a focus on officer behavior during these encounters.

Separation of U87 glioblastoma cell-derived small and medium extracellular vesicles using elasto-inertial flow focusing (a spiral channel).

Nanoscale and microscale cell-derived extracellular vesicle types and subtypes are of significant interest to researchers in biology and medicine. Extracellular vesicles (EVs) have diagnostic and therapeutic potential in terms of biomarker and nanomedicine applications. To enable such applications, EVs must be isolated from biological fluids or separated from other EV types. Developing methods to fractionate EVs is of great importance to EV researchers. Our goal was to begin to develop a device that would separate medium EVs (mEVs, traditionally termed microvesicles or shedding vesicles) and small EVs (sEVs, traditionally termed exosomes) by elasto-inertial effect. We sought to develop a miniaturized technology that works similar to and provides the benefits of differential ultracentrifugation but is more suitable for EV-based microfluidic applications. The aim of this study was to determine whether we could use elasto-inertial focusing to re-isolate and recover U87 mEVs and sEVs from a mixture of mEVs and sEVs isolated initially by one round of differential ultracentrifugation. The studied spiral channel device can continuously process 5 ml of sample fluid per hour. Using the channel, sEVs and mEVs were recovered and re-isolated from a mixture of U87 glioma cell-derived mEVs and sEVs pre-isolated by one round of differential ultracentrifugation. Following two passes through the spiral channel, approximately 55% of sEVs were recovered with 6% contamination by mEVs (the recovered sEVs contained 6% of the total mEVs). In contrast, recovery of U87 mEVs and sEVs re-isolated using a typical second centrifugation wash step was only 8% and 53%, respectively. The spiral channel also performed similar to differential ultracentrifugation in reisolating sEVs while significantly improving mEV reisolation from a mixture of U87 sEVs and mEVs. Ultimately this technology can also be coupled to other microfluidic EV isolation methods in series and/or parallel to improve isolation and minimize loss of EV subtypes.

Effects of second responder programs on repeat incidents of family abuse: An updated systematic review and meta-analysis.

Background: Family abuse is a recurrent phenomenon within a select population of households. This form of abuse can include any physical or psychological harassment that occurs between family or household members, and often involves complex mental and emotional issues that are resistant to intervention. Traditional criminal justice strategies for combating this issue have evolved over time but have frequently demonstrated limited success. Within the past few decades, multiagency programs to address repeat family abuse have gained popularity. One such program, termed "second responders," teams police officers with social service workers, victim advocates, or counselors to conduct follow-up visits with victims of family abuse following a complaint. Second responders seek to educate victims about the cyclical nature of family abuse, engage in safety planning, and/or provide service referrals. These interventions are based on the premise that victims are more likely to be receptive to crime prevention opportunities immediately following victimization. Second responder interventions have received support from the US Department of Justice and their adoption has spread in both the United States and internationally, however, there remains little conclusive evidence on their effects. Objectives: To update and extend the findings of the prior second responders systematic review and meta-analysis by synthesizing the results of published and unpublished second responder evaluations through October of 2021. This review also examines the use of victim services as a secondary outcome and incorporates a number of additional moderator analyses. Search Methods: The Global Policing Database (GPD), a repository of all experimental and quasi-experimental evaluations of policing interventions conducted since 1950, was searched using keywords related to second responder interventions and repeat family violence from 2004 to December 2019 (https://gpd.uq.edu.au/s/gpd/page/about). This search was also supplemented with additional strategies, such as reference harvesting of prior reviews, searching 2020 and 2021 volumes of leading academic journals, reviewing the reference lists of eligible studies, searching additional gray literature repositories focused on domestic violence, and consulting with eligible study authors. Selection Criteria: Eligible studies were required to include a treatment group that received the second responder intervention and a comparison group that did not. Assignment to these conditions could be either experimental or quasi-experimental, but quasi-experimental studies were required to use either matched comparison groups or multivariate analysis methods to control for confounding factors. Eligibility was limited to studies reporting on at least one measure of repeat family abuse, such as intimate partner violence, elder abuse, or general family abuse. Measures of repeat abuse could be based on either official (i.e., police data) or unofficial (i.e., victim survey data) data sources. Data Collection and Analysis: Five new studies were identified between 2004 and 2019, all of which contained sufficient data for the calculation of at least one effect size. Along with the 10 studies included in the prior review, a total of 15 studies and 29 distinct effect sizes were analyzed across three outcome constructs. Effect sizes were calculated as logged odds ratios and results were synthesized using random effects models with restricted maximum likelihood estimation. Final results were exponentiated to represent the percentage point difference in the odds of a given outcome for treatment groups relative to control groups. Risk of bias was assessed using items adapted from the Cochrane Risk of Bias tools for experimental and quasi-experimental studies. Eligible studies were generally considered to be of low risk of bias, however, issues with survey success/contact rates and the analytical approaches to these problems led to concern in several studies. Results: These analyses suggest that second responder interventions produced no significant effects on either police or victim-reported measures of repeat family abuse, in aggregate. However, findings from the more rigorous experimental studies indicated that second responder interventions were associated with a statistically significant 22% (95% confidence interval [CI] [1.04, 1.43]) increase in the odds of a police-reported repeat family abuse incident, with no significant variability in individual study results. Additionally, studies that measured the use of victim services as a secondary outcome were associated with a statistically significant 9% (95% CI [1.02, 1.16]) increase in the odds of service use for treatment groups relative to control groups. Several study characteristics also proved to be important moderators of treatment effects. Increases in the speed of the second response were associated with significant decreases in the odds of a victim-reported repeat incident, and studies that measured repeat family abuse using households were associated with significantly higher odds of a police-reported repeat incident, compared to studies that used the same victim or victim/offender pairing more generally. Authors' Conclusions: Second responder interventions are undoubtedly appealing based on their logic and intentions. Yet, well-intentioned programs with sound logic can still backfire, and the results of this updated review provide evidence that may be suggestive of a backfire effect. Even so, any firm conclusions from this review are limited by a lack of knowledge on the mechanisms operating in between the implementation of the second response intervention and the observed effects, as well as the small sample sizes involved in many analyses. While it seems clear that these programs are not producing any broad reductions in self-reported victimization, the increase in police-reported violence seen in experimental studies could indicate either a true increase in abuse or an increased willingness to call the police. The lack of observed impact on victim-reported violence would suggest the latter, but without more specific measures, such conclusions should be avoided. If these results are indicative of increased reporting, however, many may consider this a desirable outcome, particularly given the often-underreported nature of family abuse and the potential for increased reporting to lead to long-term reductions in abuse. Furthermore, these results provide an indication that second responder programs can produce other intended effects, such as increasing the retention of victim services, and that the specific characteristics of these interventions may moderate their effects. It is unclear why elements such as the immediacy of the second response or the unit of analysis being evaluated would impact study results, but these observations are consistent with the theory that domestic violence interventions must capitalize on short windows of opportunity and create separation between victims and offenders to reduce exposure and subsequent victimization. This potential indicates a need for more research on second responder programs, but specifically research that examines these moderating characteristics and mechanisms. Even in light of this potential, second responder programs do not, on average, appear to reduce the prevalence of repeat family abuse. Given the presence of alternative (and possibly more effective) domestic violence interventions that now exist (e.g., Safe Dates, Shifting Boundaries, Green Dot, etc.), it seems that policymakers may wish to look elsewhere for efforts to reduce family abuse.

Experiment, theory, and simulation of a flow-electrical-split flow thin particle separation device.

Herein, we describe the simulation of a novel flow-electrical-split flow thin (Fl-El-SPLITT) separation device and validate it using existing theory and experimentation for the first time using polystyrene particles of 28 and 1000 nm diameters. The fraction of particles exiting selected ports with DC El-SPLITT is predicted with existing theory, but the theory does not include AC fields, nor does it incorporate the use of crossflows. Using DC fields the El-SPLITT simulation and theory calculated transition points result in the same values. These calculated values accurately predict the experimentally obtained transition point using a 50:50 outlet splitting plane (OSP). Relative to actual experimentally obtained transition points, the calculated values lag behind for a 90:10 OSP, and lead ahead for a 10:90 OSP. The simulation explains trends seen in AC testing, and reasonably predicts the fraction of particles exiting each port. As DC current increases, the amount of AC current required to scatter the particles away from the DC-intended port decreases. The simulation also models a crossflow in a SPLITT system with a DC current applied in a direction opposite the crossflow with some success. Long term steady-state testing without crossflows shows a DC voltage dependent loss of particles. At 8 V DC, total recovery of 28 and 1000 nm particles was 70% and 26%, respectively. This work effectively models a new Fl-El-SPLITT system via Matlab simulation by demonstrating key experimental results such as the influence of DC, AC, and crossflows on the SPLITT separation of polystyrene particles.

Development and Testing of a Continuous Flow-Electrical-Split-Flow Lateral Transport Thin Separation System (Fl-El-SPLITT).

In this work, a new high-volume, continuous particle separation device that separates based upon size and charge is described. Two continuous flow-electrical-split-flow lateral transport thin (Fl-El-SPLITT) device architectures (a platinum electrode on a porous membrane and a porous graphite electrode under a membrane) were developed and shown to improve particle separations over a purely electrical-SPLITT device. The graphite FL-El-SPLITT device architecture achieved the best separation of approximately 60% of small (28 nm) vs large (1000 nm) polystyrene particles. Fl-El-SPLITT (platinum) achieved a 75% separation on a single pass using these same particles. Fl-El-SPLITT (platinum) achieved a moderate 26% continuous separation of U87 glioma cell-derived small extracellular vesicles (EVs) from medium EVs. Control parameter testing showed that El-SPLITT continuously directed particle motility within a channel to exit a selected port based upon the applied voltage using either direct current or alternating current. The transition from one port to the other was dependent upon the voltage applied. Both large and small polystyrene particles transitioned together rather than separating at each of the applied voltages. These data present the first ever validation of El-SPLITT in continuous versus batch format. The Fl-El-SPLITT device architecture, monitoring, and electrical and fluid interfacing systems are described in detail for the first time. Capabilities afforded to the system by the flow addition include enhanced particle separation as well as the ability to filter out small particles or desalinate fluids. High-throughput continuous separations based upon electrophoretic mobility will be streamlined by this new technique that combines electrical and flow fields into a single device.

Updated protocol: Effects of second responder programs on repeat incidents of family abuse: An updated systematic review and meta-analysis.

The US Department of Justice has extensively funded second responder programs. In England and Wales, funding of follow-up with victims is largely funded by local Police and Crime Commissioners. While these programs rapidly gained popularity in the United States and are gaining popularity in other countries as well, the evidence regarding their effectiveness is mixed. Although some research has indicated that second responder programs can prevent repeat victimization, several experimental studies have suggested that these programs may actually increase the odds of abuse recurring. The purpose of the review is to compile and synthesize published and unpublished empirical studies of the effects of second responder programs on repeat incidents of family violence, including those studies completed after the original review. The Global Police Database (http://www.gpd.uq.edu.au/) provides a resource unavailable at the time of the initial review that will ensure that a comprehensive set of qualifying studies is identified. In the updated review, we will address the following questions: 1. What impact do second responder programs have on the number of subsequent calls to the police? 2. What impact do second responder programs have on abuse as measured on victim surveys? 3. Does the impact of second responder programs differ between experimental and quasi-experimental studies or studies that employ different methods of drawing samples? Building on the original review, we also aim to expand our examination of effect size heterogeneity given sufficient data to do so. For instance, given the proposition that there may be only a small window of opportunity to intervene into the lives of family violence victims after an incident, the amount of time that elapses between a family violence call and the second response may be an important moderator of programmatic effects. Additional factors that could impact the effect of the intervention include the length of the follow-up data collection period, the type of family violence complaint (e.g., intimate partner violence vs. elder abuse), and the sociodemographic characteristics of the victim and the offender (see generally Sherman, 2018). Ultimately, this review seeks not only to update the results of the prior review with additional research, but also to explore the mechanisms behind the observed effects in a way that provides utility for future policy creation.

An automated instrument for intrauterine insemination sperm preparation.

Sperm preparation is critical to achieving a successful intrauterine insemination and requires the processing of a semen sample to remove white blood cells, wash away seminal plasma, and reduce sample volume. We present an automated instrument capable of performing a sperm preparation starting with a diluted semen sample. We compare our device against a density gradient centrifugation by processing 0.5 mL portions of patient samples through each treatment. In 5 min of operating time, the instrument recovers an average of 86% of all sperm and 82% of progressively motile sperm from the original sample while removing white blood cells, replacing the seminal plasma, and reducing the volume of the sample to the clinically required level. In 25 min of operating time, density gradient centrifugation recovers an average of 33% of all sperm and 41% of progressively motile sperm. The automated instrument could improve access to IUI as a treatment option by allowing satellite doctor's offices to offer intrauterine insemination as an option for patients without the clinical support required by existing methods.

Characterization of Human Glioblastoma versus Normal Plasma-Derived Extracellular Vesicles Preisolated by Differential Centrifugation Using Cyclical Electrical Field-Flow Fractionation.

Although many properties for small extracellular vesicles (sEVs, formerly termed "exosomes") isolated at ∼100 000g are known, a wide range of values are reported for their electrophoretic mobility (EM) measurements. This paper reports for the first time the effect of dilution on the EM of U87 glioblastoma cell-derived and plasma-derived sEVs and medium size EVs (mEVs, commonly termed "oncosomes") preisolated by differential centrifugation. Furthermore, the effect of resalting on the EM of sEVs and mEVs was evaluated. The EM of U87 sEVs and U87 mEVs showed an increase as the salt concentration decreased to 0.005% of the initial salt concentration. However, for the plasma sEVs and plasma mEVs, the electrophoretic mobility increased as the salt concentration decreased to 0.01% of the initial salt concentration and then increased to its initial value when the salt concentration decreased to 0.005% of the initial salt concentration. For both U87 and plasma sEVs and mEVs, the EM remained almost constant when the concentration of the particles changed and the salt concentration was kept the same as its initial value. This indicates that the EM of EVs is only a function of the salt concentration of the buffer and is independent of the concentration of the particles. The sEVs and mEVs were separated with cyclical ElFFF for the first time. The results indicate that ElFFF was able to fractionate the EVs, and a crescent-shaped trend was found for the retention time when the applied AC voltage was altered (increased).

Characterization and differential retention of Q beta bacteriophage virus-like particles using cyclical electrical field-flow fractionation and asymmetrical flow field-flow fractionation.

Virus-like particles (VLPs) are widely used in medicine, but can be difficult to characterize and isolate from aggregates. In this research, primarily cyclical electrical field-flow fractionation (CyElFFF) coupled with multi-angle light scattering (MALS), and dynamic light scattering (DLS) detectors, was used for the first time to perform size and electrical characterization of three different types of Q beta bacteriophage virus-like particles (VLPs): a blank Q beta bacteriophage which is denoted as VLP and two conjugated ones with different peptides. The CyElFFF results were verified with transmission electron microscopy (TEM). Asymmetrical flow field-flow fractionation (AF4) coupled with MALS was also applied using conditions similar to those used in the CyElFFF experiments, and the results of the two techniques were compared to each other. Using these techniques, the size and electrophoretic characteristics of the fractionated VLPs in CyElFFF were obtained. The results indicate that CyElFFF can be used to obtain a clear distribution of electrophoretic mobilities for each type of VLP. Accordingly, CyElFFF was able to differentially retain and isolate VLPs with high surface electric charge/electrophoretic mobility from the ones with low electric charge/electrophoretic mobility. Regarding the size characterization, the size distribution of the eluted VLPs was obtained using both techniques. CyElFFF was able to identify subpopulations that did not appear in the AF4 results by generating a shoulder peak, whereas AF4 produced a single peak. Different size characteristics of the VLPs appearing in the shoulder peak and the main peak indicate that CyElFFF was able to isolate aggregated VLPs from the monomers partially. Graphical abstract.

Problem-oriented policing for reducing crime and disorder: An updated systematic review and meta-analysis.

Background: Herman Goldstein developed problem-oriented policing (POP) to focus police on more proactively addressing chronic problems, rather than using traditional reactive efforts. POP has been utilized to target a wide range of problems and has become commonly used in agencies across the United States and the world, although implementation is often uneven. POP interventions commonly use the SARA (scanning, analysis, response, assessment) model to identify problems, carefully analyze the conditions contributing to the problem, develop a tailored response to target these underlying factors, and evaluate outcome effectiveness. Objectives: To extend and update the findings of the original POP systematic review by synthesizing the findings of published and unpublished evaluations of POP through December 2018 to assess its overall impacts on crime and disorder. The review also examined impacts of POP on crime displacement, police financial costs, and noncrime outcomes. Search Methods: Searches using POP keywords of the Global Policing Database at the University of Queensland were conducted to identify published and unpublished evaluations between 2006 and 2018. We supplemented these searches with forward searches, hand searches of leading journals and the Center for Problem-Oriented Policing, and consultation with experts. Selection Criteria: Eligible studies had to include a target area or group that received a POP intervention AND a control area/group that received standard police services. The control condition could be either experimental or quasi-experimental. Units of analysis could be places or people. We defined POP as studies that generally followed the tenets of the SARA model. Data Collection and Analysis: We identified 39 new (published between 2006 and 2018) studies that met our eligibility criteria as an evaluation of POP. Twenty-four of these studies had sufficient data available to calculate an effect size. Along with the 10 studies from our initial systematic review of POP, these 34 studies are included in our meta-analytic review of POP. Nine of these studies were randomized experiments and 25 were quasi-experiments. We calculated effect sizes for each study using Cohen's D and relative incidence risk ratios and used random effects meta-analyses to synthesize studies. Results: Our meta-analyses suggest statistically significant impacts of POP. Our relative incident risk ratio analysis of mean effects suggests a 33.8% reduction in crime/disorder in the POP treatment areas/groups relative to the controls. We find no evidence of significant crime displacement as a result of POP and some evidence for a greater likelihood of a diffusion of crime control benefits. Few studies assessed noncrime outcomes, but our narrative review suggests POP is cost-effective, but has limited impacts on fear of crime, legitimacy, and collective efficacy. Authors' Conclusions: Our review provides strong and consistent evidence that POP is an effective strategy for reducing crime and disorder. There is a great deal of heterogeneity in the magnitude of effect sizes across factors such as study type, study rigor and crime type. Despite this heterogeneity, 31 out of 34 studies (91.2%) have effect sizes in favor of a treatment effect and the overall mean effect is positive and significant in all of our models.

Exosome Isolation: Cyclical Electrical Field Flow Fractionation in Low-Ionic-Strength Fluids.

The influence of buffer substitution and dilution effects on exosome size and electrophoretic mobility were shown for the first time. Cyclical electrical field flow fractionation (Cy-El-FFF) in various substituted fluids was applied to exosomes and other particles. Tested carrier fluids of deionized (DI) water, 1× phosphate buffered saline (PBS), 0.308 M trehalose, and 2% isopropyl alcohol (IPA) influenced Cy-El-FFF-mediated isolation of A375 melanoma exosomes. All fractograms revealed a crescent-shaped trend in retention times with increasing voltage with the maximum retention time at ∼1.3 V AC. A375 melanoma exosome recovery was approximately 70-80% after each buffer substitution, and recovery was independent of whether the sample was substituted into 1× PBS or DI water. Exosome dilution in deionized water produced a U-shaped dependence on electrophoretic mobility. The effect of dilution using 1× PBS buffer revealed a very gradual change in electrophoretic mobility of exosomes from ∼-1.6 to -0.1 µm cm/s V, as exosome concentration was decreased. This differed from the use of DI water, where a large change from ∼-5.5 to -0.1 µm cm/s V over the same dilution range was observed. Fractograms of separated A375 melanoma exosomes in two substituted low-ionic-strength buffers were compared with synthetic particle fractograms. Overall, the ability of Cy-El-FFF to separate exosomes based on their size and charge is a highly promising, label-free approach to initially catalogue and purify exosome subtypes for biobanking as well as to enable further exosome subtype interrogations.

Effect of Payment Model on Patient Outcomes in Outpatient Physical Therapy.

Although the literature has well recognized the effectiveness of physical therapy for treating musculoskeletal injuries, reimbursement is evolving towards value-based or alternative payment models and away from procedure orientated, fee-for-service in the outpatient setting. Alternative models include cased-based clinics, pay-for-performance, out-of-network services, accountable care organizations, and concierge practices. There is the possibility that alternative payment models could produce different and even superior patient outcomes. Physical therapists should be alert to this possibility, and research is warranted in this area to conclude if outcomes in patient care are related to method of reimbursement.

A Pathology of Mesh and Time: Dysejaculation, Sexual Pain, and Orchialgia Resulting From Polypropylene Mesh Erosion Into the Spermatic Cord.

OBJECTIVE: The ubiquitous use of polypropylene mesh in hernia surgery has spawned a new clinical syndrome: chronic post-herniorrhaphy neuralgia. A subset of that clinical picture is dysejaculation, sexual pain, and orchialgia. We propose to identify the processes that lead to that pain. SUMMARY OF BACKGROUND DATA: Specimens of vas adherent to polypropylene mesh, explanted in an attempt to control severe, life-changing inguinodynia are extremely difficult to obtain. This scarcity may be due to ingrained attitudes in our society about removal of vas and/or testicles for whatever reason. Attempts at preserving such damaged structures may paradoxically contribute to the chronicity and severity of such pain. METHODS: The medical files of patients who had mesh specimens explanted because of severe chronic post-herniorrhaphy pain were reviewed to identify cases with recorded evidence, at the time of surgery, of involvement of spermatic cord/vas deferens with mesh. These criteria were met in 13 cases and the specimens were analyzed histologically. RESULTS: The vas deferens was resected in 83% (5 of 6) of the patients with a history of sexual pain and/or dysejaculation (vs 14% of those without a history of sexual pain, P = 0.03). Histology demonstrated unequivocal mesh invasion of the spermatic cord, where the initial damage occurred to nerves (autonomic, somatic), then to the smooth muscle of the vas while the lumen remained patent. In 50% (3 of 6), the vas and other cord structures appeared to be completely invaded by the mesh and replaced by scar tissue. CONCLUSIONS: Irreversible damage of the nerves and vas musculature due to mesh migration is one of the mechanisms for sexual pain and dysejaculation. Attempts at all cost to preserve elements of the spermatic cord may not be justified in cases of severe pain, especially sexual pain (and/or dysejaculation) and intraoperative finding of cord involvement by the mesh. Vasectomy with mesh removal may well be indicated and be considered not a radical procedure but a conservative measure given the severity of the pain!

A review of exosome separation techniques and characterization of B16-F10 mouse melanoma exosomes with AF4-UV-MALS-DLS-TEM.

Exosomes participate in cancer metastasis, but studying them presents unique challenges as a result of their small size and purification difficulties. Asymmetrical field flow fractionation with in-line ultraviolet absorbance, dynamic light scattering, and multi-angle light scattering was applied to the size separation and characterization of non-labeled B16-F10 exosomes from an aggressive mouse melanoma cell culture line. Fractions were collected and further analyzed using batch mode dynamic light scattering, transmission electron microscopy and compared with known size standards. Fractogram peak positions and computed radii show good agreement between samples and across fractions. Ultraviolet absorbance fractograms in combination with transmission electron micrographs were able to resolve subtle heterogeneity of vesicle retention times between separate batches of B16-F10 exosomes collected several weeks apart. Further, asymmetrical field flow fractionation also effectively separated B16-F10 exosomes into vesicle subpopulations by size. Overall, the flow field flow fractionation instrument combined with multiple detectors was able to rapidly characterize and separate exosomes to a degree not previously demonstrated. These approaches have the potential to facilitate a greater understanding of exosome function by subtype, as well as ultimately allow for "label-free" isolation of large scale clinical exosomes for the purpose of developing future exosome-based diagnostics and therapeutics.