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A novel method for the determination of per- and polyfluoroalkyl substances (PFAS) in groundwater is presented using a subsample, matrix-matched calibrators, 96-well plate solid phase extraction (SPE), and ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Accuracy, precision, measurement of uncertainty (MOU), method detection limit (MDL), method quantitation limit (MQL), analytical measurement range, interferences/ion suppression, and analyte stability were determined as part of the in-house method validation. The method quantitates 42 PFAS compounds from nine different compound classes. Accuracy for the reference material (RM) and matrix spike (MS) ranged from 52.3 to 117.8 %, and precision for the MS and matrix spike duplicate (MSD) had a coefficient of variation (CV) from 2.0 % to 23.3 %. MDLs spanned from 0.07 to 1.97 ng L-1, with MQLs ranging from 0.20 to 5.90 ng L-1. Suppression studies determined that iron and manganese have effects on analytes that do not have paired isotopically labeled standards. The results from the in-house validation indicated that this Michigan Department of Health and Human Services laboratory developed test meets the necessary accuracy, precision, MDL, MQL and reporting limits requirement established by the laboratory's quality system essentials (QSEs) and select criteria from the Department of Defense (DoD) Quality Systems Manual for Environmental Laboratories and American Industrial Hygiene Association Laboratory Accreditation Program, LLC (AIHA LAP, LLC) accrediting International Standard Organization (ISO/IEC 17025:2017) check list.

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OBJECTIVE: Standard methods to evaluate tracheal pathology in children, including bronchoscopy, may require general anesthesia. Conventional dynamic proximal airway imaging in noncooperative children requires endotracheal intubation and/or medically induced apnea, which may affect airway mechanics and diagnostic performance. We describe a technique for unsedated dynamic volumetric computed tomography angiography (DV-CTA) of the proximal airway and surrounding vasculature in children and evaluate its performance compared to the reference-standard of rigid bronchoscopy. METHODS: Children who had undergone DV-CTA and bronchoscopy in one-year were retrospectively identified. Imaging studies were reviewed by an expert reader blinded to the bronchoscopy findings of primary or secondary tracheomalacia. Airway narrowing, if present, was characterized as static and/or dynamic, with tracheomalacia defined as >50% collapse of the tracheal cross-sectional area in exhalation. Pearson correlation was used for comparison. RESULTS: Over a 19-month period, we identified 32 children (median age 8 months, range 3-14 months) who had undergone DV-CTA and bronchoscopy within a 90-day period of each other. All studies were unsedated and free-breathing. The primary reasons for evaluation included noisy breathing, stridor, and screening for tracheomalacia. There was excellent agreement between DV-CTA and bronchoscopy for diagnosis of tracheomalacia (κ = 0.81, p < 0.001), which improved if children (n = 25) had the studies within 30 days of each other (κ = 0.91, p < 0.001). CTA provided incremental information on severity, and cause of secondary tracheomalacia. CONCLUSION: For most children, DV-CTA requires no sedation or respiratory manipulation and correlates strongly with bronchoscopy for the diagnosis of tracheomalacia. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:410-416, 2023.

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Audience: The Zipperator training model is designed for emergency medicine resident physicians and physicians. Introduction: Zipper entrapment injuries are an uncommon cause of penile injury in the emergency department, representing an incidence of less than 0.5% of pediatric emergency department visits.1 However, they are one of the most common causes of genital injuries in young boys.1,2 Various methods proposed for releasing the entrapped tissue range from the use of mineral oil as lubrication to techniques to release the zipper mechanism or, in extreme cases, surgical procedures.3-6 A well-designed simulated task trainer would allow learners to practice these methods in a controlled environment conducive to learning 7,8. Given the low frequency of the chief complaint and with a wide variety of release techniques available, the purpose of this study was to build a simulation model that could improve learner confidence in troubleshooting this rarely performed procedure. Although past studies have designed similar task trainers, this novel model was built using a low-cost device ("Operation") to provide real-time alarm noises that reasonably simulate distress and procedural anxiety for both the patient and provider. Although pain and anxiety are separate outcomes from zipper entrapment release, including a component of these emotions may mimic the same emotional states that patients, their parental unit, and perhaps their provider may experience regarding this chief complaint given its rarity, anatomic vulnerability, and the overall sensitivity of the complaint's nature. Educational Objectives: After training on the Zipperator, learners will be able to:Demonstrate at least two techniques for zipper release and describe how methods would extrapolate to a real patient.Verbalize increased comfort with the diagnosis of zipper entrapment.Present a plan of care for this low-volume, high-anxiety presentation. Educational Methods: As part of a voluntary Emergency Medicine curriculum at two different sites, we constructed an inexpensive model for penile zipper entrapment using a household gameboard, "Operation," and materials that are easily obtainable and assembled in any emergency department. "Operation" was selected for its ability to produce alarm noises in response to excessive movement, which would reasonably simulate distress and procedural anxiety that may be experienced by both the patient and provider. This task trainer was used to teach medical students and post graduate year (PGY) 1-4 resident learners. A brief hypothetical situation was presented to learners, highlighting patient and paternal unit anxiety. Following this, learners were given a survey and asked to complete pre-model training questions immediately prior to using the simulated model. Learners were then given the opportunity for hands-on skills-based practice. Postmodel training questions were made available in the same survey immediately following the exercise. Research Methods: This exercise was offered at two sites over a two-year period. Sixty learners participated in the exercise. Participation was voluntary, was not graded nor shared with the residency director, and all feedback was formative in nature. Selected faculty and research assistants provided asynchronous opportunities for learners to practice on the model. Before the exercise, the faculty or research assistant on site presented a brief hypothetical situation to simulate patient and paternal unit anxiety that could be expected in this chief complaint. Each learner was then allowed to select a variety of tools and methods to practice zipper entrapment release. Learners were asked to begin a survey prior to training on the model, and then complete the survey immediately after training on the model to evaluate its educational value. The survey created for this study consisted of a structured questionnaire that contained close-ended questions. Measures evaluated include experience with prior zipper entrapments, comfort with zipper entrapments before and after training on the simulated model, and user experience. Results: Before the exercise, 68.3% of learners described their comfort with managing future zipper entrapments as very uncomfortable or totally uncomfortable. Although only 8.3% of learners had treated the zipper entrapment complaint prior to the exercise, 100% of those who had experienced treating the complaint felt that the simulated model was at least somewhat reflective of their experience with a real patient. 71.7% of the learners found the experience enjoyable, although 20% found the experience totally unenjoyable, of note, for unclear reasons and with unclear significance or etiology. After the exercise, 71.7% of learners indicated they felt comfortable to very comfortable regarding future cases of zipper entrapment. Discussion: Through the use of a well-known household board game and supplies commonly found in the emergency department, we created a simulated model that could be easily replicated. This simple model provided practice of the hand motions necessary for zipper entrapment release, as well as familiarity with the mental and physical approaches to dislodging the entrapment. The resident physicians who had had a prior zipper entrapment patient reported the model was somewhat similar to actual patient encounters. Overall, this model was well-received by the learners, with most expressing it was enjoyable and feeling it increased their confidence for treating this chief complaint. Some learners had noted the experience was totally unenjoyable. This measure may not be an appropriate endpoint, however, and incongruencies may be addressed by implementing prizes or friendly competition for enjoyment. Another limitation of this study is the leap taken between movement and patient comfort. While possible that learners can manipulate the model to reduce movement of the needle without meaningful reduction in zipper movement, observation by the instructor was sufficient to ensure this finding was not observed in our learner population. We therefore submit this cheap, simple model as a potential method to teach approaches to teaching a low frequency, high anxiety chief complaint. Topics: Penile entrapment model, penile entrapment release, Emergency Medicine, Urology, Clinical/Procedural Skills Training.

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The canonical Wnt and PI3K/Akt/mTOR pathways both play critical roles in brain development early in life. There is extensive evidence of how each pathway is involved in neuronal and synaptic maturation, however, how these molecular networks interact requires further investigation. The present study examines the effect of neuronal subset-specific deletion of phosphatase and tensin homolog (Pten) in mice on Wnt signaling protein levels and associated cognitive impairments. PTEN functions as a negative regulator of the PI3K/Akt/mTOR pathway, and mutations in Pten can result in cognitive and behavioral impairments. We found that deletion of Pten resulted in elevated Dvl2, Wnt5a/b, and Naked2, along with decreased GSK3ß hippocampal synaptosome protein expression compared to wild type mice. Aberrations in the canonical Wnt pathway were associated with learning and memory deficits in Pten knockout mice, specifically in novel object recognition and the Lashley maze. This study demonstrates that deletion of Pten not only significantly impacts PI3K/Akt/mTOR signaling, but affects proper functioning of the Wnt signaling pathway. Overall, these findings will help elucidate how the PI3K/Akt/mTOR pathway intersects with Wnt signaling to result in cognitive impairments, specifically in memory.

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MEMS mirrors are currently used in many applications to steer beams of light. An area of continued research is developing mirrors with varifocal capability that allows the beam to be shaped and focused. In this work, we study the varifocal capability of a 380 µm diameter, thermally actuated MEMS mirror with a ± 40° tip-tilt angle and a radius of curvature between -0.48 mm to 20.5 mm. Light is coupled to the mirror via a single mode optical fiber, similar to an indoor optical wireless communication architecture. The performance of the mirror is characterized with respect to (1) the profile of the reflected beam as the mirror deforms and (2) the mirror's impact when integrated into an optical communication system. We found that the mirror can focus light to a beam with a 0.18° half-angle divergence. Additionally, the ability to change the shape of fiberized light from a wide to narrow beam provides an unmatched level of dynamic control and significantly improves the bit error rate in an optical communication system.

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Many freshwater lakes undergo seasonal stratification, where the formation of phototrophic blooms in the epilimnion and subsequent sedimentation induces hypoxia/anoxia in the thermocline and hypolimnion. This autochthonously produced biomass represents a major seasonal organic input that impacts the entire ecosystem. While the limnological aspects of this process are fairly well documented, relatively little is known regarding the microbial community response to such events, especially in the deeper anoxic layers of the water column. Here, we conducted a spatiotemporal survey of the particle-associated and free-living microbial communities in a warm monomictic freshwater reservoir (Grand Lake O' the Cherokees) in northeastern Oklahoma, USA. Pre-stratification samples (March) harbored a homogeneous community throughout the oxygenated water column dominated by typical oligotrophic aquatic lineages (acl clade within Actinobacteria, and Flavobacterium within the Bacteroidetes). The onset of phototrophic blooming in June induced the progression of this baseline community into two distinct trajectories. Within the oxic epilimnion, samples were characterized by the propagation of phototrophic (Prochlorococcus), and heterotrophic (Planctomycetes, Verrucomicrobia, and Beta-Proteobacteria) lineages. Within the oxygen-deficient thermocline and hypolimnion, the sedimentation of surface biomass induced the development of a highly diverse community, with the enrichment of Chloroflexi, "Latescibacteria", Armatimonadetes, and Delta-Proteobacteria in the particle-associated fraction, and Gemmatimonadetes and "Omnitrophica" in the free-living fraction. Our work documents the development of multiple spatially and temporally distinct niches during lake stratification, and supports the enrichment of multiple yet-uncultured and poorly characterized lineages in the lake's deeper oxygen-deficient layers, an ecologically relevant microbial niche that is often overlooked in lakes diversity surveys.

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The ability to actively shift the primary resonance of a 2D scanning micromirror allows the user to set the scanning direction, set the scanning frequency, and lift otherwise degenerate modes in a symmetrically designed system. In most cases, resonant scanning micromirrors require frequency stability in order to perform imaging and projection functions properly. This paper suggests a method to tune the tip and tilt resonant frequencies in real time while actively suppressing or allowing degeneracy of the two modes in a symmetric electrothermal micromirror. We show resonant frequency tuning with a range of degeneracy separation of 470 Hz or by approximately ±15% and controllable coupling.

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BACKGROUND: Algae encompass a wide array of photosynthetic organisms that are ubiquitously distributed in aquatic and terrestrial habitats. Algal species often bloom in aquatic ecosystems, providing a significant autochthonous carbon input to the deeper anoxic layers in stratified water bodies. In addition, various algal species have been touted as promising candidates for anaerobic biogas production from biomass. Surprisingly, in spite of its ecological and economic relevance, the microbial community involved in algal detritus turnover under anaerobic conditions remains largely unexplored. RESULTS: Here, we characterized the microbial communities mediating the degradation of Chlorella vulgaris (Chlorophyta), Chara sp. strain IWP1 (Charophyceae), and kelp Ascophyllum nodosum (phylum Phaeophyceae), using sediments from an anaerobic spring (Zodlteone spring, OK; ZDT), sludge from a secondary digester in a local wastewater treatment plant (Stillwater, OK; WWT), and deeper anoxic layers from a seasonally stratified lake (Grand Lake O' the Cherokees, OK; GL) as inoculum sources. Within all enrichments, the majority of algal biomass was metabolized within 13-16 weeks, and the process was accompanied by an increase in cell numbers and a decrease in community diversity. Community surveys based on the V4 region of the 16S rRNA gene identified different lineages belonging to the phyla Bacteroidetes, Proteobacteria (alpha, delta, gamma, and epsilon classes), Spirochaetes, and Firmicutes that were selectively abundant under various substrate and inoculum conditions. Within all kelp enrichments, the microbial communities structures at the conclusion of the experiment were highly similar regardless of the enrichment source, and were dominated by the genus Clostridium, or family Veillonellaceae within the Firmicutes. In all other enrichments the final microbial community was dependent on the inoculum source, rather than the type of algae utilized as substrate. Lineages enriched included the uncultured groups VadinBC27 and WCHB1-69 within the Bacteroidetes, genus Spirochaeta and the uncultured group SHA-4 within Spirochaetes, Ruminococcaceae, Lachnospiraceae, Yongiibacter, Geosporobacter, and Acidaminobacter within the Firmicutes, and genera Kluyvera, Pantoea, Edwardsiella and Aeromonas, and Buttiauxella within the Gamma-Proteobaceteria order Enterobacteriales. CONCLUSIONS: Our results represent the first systematic survey of microbial communities mediating turnover of algal biomass under anaerobic conditions, and highlights the diversity of lineages putatively involved in the degradation process.

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Background. The anaerobic gut fungi (phylum Neocallimastigomycota) represent a promising source of novel lignocellulolytic enzymes. Here, we report on the cloning, expression, and characterization of a glycoside hydrolase family 39 (GH39) enzyme (Bgxg1) that is highly transcribed by the anaerobic fungus Orpinomycessp. strain C1A under different growth conditions. This represents the first study of a GH39-family enzyme from the anaerobic fungi. Methods. Using enzyme activity assays, we performed a biochemical characterization of Bgxg1 on a variety of substrates over a wide range of pH and temperature values to identify the optimal enzyme conditions and the specificity of the enzyme. In addition, substrate competition studies and comparative modeling efforts were completed. Results. Contrary to the narrow range of activities (ß-xylosidase or α-L-iduronidase) observed in previously characterized GH39 enzymes, Bgxg1 is unique in that it is multifunctional, exhibiting strong ß-xylosidase, ß-glucosidase, ß-galactosidase activities (11.5 ± 1.2, 73.4 ± 7.15, and 54.6 ± 2.26 U/mg, respectively) and a weak xylanase activity (10.8 ± 1.25 U/mg), as compared to previously characterized enzymes. Further, Bgxg1 possesses extremely high affinity (as evident by the lowest K m values), compared to all previously characterized ß-glucosidases, ß-galactosidases, and xylanases. Physiological characterization revealed that Bgxg1 is active over a wide range of pH (3-8, optimum 6) and temperatures (25-60 °C, optimum 39 °C), and possesses excellent temperature and thermal stability. Substrate competition assays suggest that all observed activities occur at a single active site. Using comparative modeling and bioinformatics approaches, we putatively identified ten amino acid differences between Bgxg1 and previously biochemically characterized GH39 ß-xylosidases that we speculate could impact active site architecture, size, charge, and/or polarity. Discussion. Collectively, the unique capabilities and multi-functionality of Bgxg1 render it an excellent candidate for inclusion in enzyme cocktails mediating cellulose and hemicellulose saccharification from lignocellulosic biomass.

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The anaerobic fungus Orpinomyces strain C1A is capable of growth on various types of lignocellulosic substrates, and harbors an impressive reservoir of carbohydrate active enzymes (CAZymes). Using a minimum enzyme cocktail strategy, we constituted a four-component lignocellulolytic cocktail derived from highly transcribed C1A, and evaluated its efficacy against pretreated corn stover and switchgrass. Hydrolysis yields ranged between 65-77.4%, depending on the lignocellulosic substrate and pretreatment applied. Addition of a highly expressed anaerobic fungal swollenin improved hydrolysis yields by up to 7%. Compared to the commercial cocktail CTec2, these anaerobic fungal cocktails provided comparable or slightly lower hydrolysis yields. Further, the differences in efficacy between commercial and anaerobic cocktails were often only realized after extended (168 hr) incubations. Under certain conditions, the hydrolysis yields of the anaerobic fungal cocktail was slightly superior to that realized by CTec2. We attribute the observed high hydrolysis yields to the high specific activity and affinity of the individual enzymes of the cocktail, as well as the high level of synergy and multi-functionality observed in multiple components. Collectively, this effort provides a novel platform for constructing highly effective enzymes for biofuel production and represents the first lignocellulolytic enzyme cocktail created from anaerobic fungal enzymes.

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PURPOSE: Transitional care is an emerging model of health care designed to decrease preventable adverse events and associated utilization of health care through temporary follow-up after hospital discharge. This study describes the approaches and outcomes of two distinct transitional care programs serving different populations: one is provided by master's-prepared clinical nurse specialists (CNS) with a chronic disease self-management focus, another by physicians specializing in palliative care (PPCs). Existing research has shown that transitional care programs with intensive follow-up reduce hospitalizations, emergency department (ED) visits, and costs. Few studies, however, have included side-by-side descriptions of the efficacy of transitional care programs varying by healthcare providers or program focus. DESIGN: This is a retrospective cohort study comparing the number of ED visits and hospitalizations in the 120 days before and after the intervention for patients enrolled in each transitional care program. Each program included post-hospitalization home visits, but included differences in program focus (chronic disease vs. palliative), assessment and interventions, and population (rural vs. urban). Data from participants in the CNS program (September 2014 to December 2014) were analyzed (n = 98). The average age of participants was 69 years and 65% were female. Data were collected from patients from the PPC program from September 2014 to April 2015 (n = 71). Thirty participants died within 120 days after the intervention and were excluded; the remaining 41 were included in the analysis. Participants had an average age of 81 years and 63% were female. METHODS: For the CNS program, a secondary analysis of existing data was performed. For the PPC program, a review of patient charts was done to collect data on encounters. A Wilcoxon matched-pairs signed-rank test was performed to test for significance. FINDINGS: Patients in the CNS intervention had significantly fewer ED visits (p < .005) and hospitalizations (p < .005) in the 4 months after the intervention than in the 4 months before the intervention. Patients in the PPC program had a nonsignificant reduction in ED visits (p = .327) and a significant reduction in hospitalizations postintervention (p = .03). CONCLUSIONS: Both transitional programs have value in decreasing rehospitalizations. The CNS intervention also significantly reduced ED visits for their target population. Further study with randomized controlled trials is needed to allow for a better understanding of the healthcare workforce best fitted to enhance transitional care outcomes. Future study to examine the cost savings of each of the interventions is also needed. CLINICAL RELEVANCE: Transitional care programs have the potential to prevent unnecessary utilization of health care at the critical periods of transition that leave patients vulnerable to adverse events and poor outcomes.

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Clostridium perfringens, a strictly anaerobic micro-organism and inhabitant of the human intestine, has been shown to produce the azoreductase enzyme AzoC, an NAD(P)H-dependent flavin oxidoreductase. This enzyme reduces azo dyes to aromatic amines, which are carcinogenic in nature. A significant amount of work has been completed that focuses on the activity of this enzyme; however, few studies have been completed that focus on the physiology of azo dye reduction. Dye reduction studies coupled with C. perfringens growth studies in the presence of ten different azo dyes and in media of varying complexities were completed to compare the growth rates and dye-reducing activity of C. perfringens WT cells, a C. perfringens ΔazoC knockout, and Bifidobacterium infantis, a non-azoreductase-producing control bacterium. The presence of azo dyes significantly increased the generation time of C. perfringens in rich medium, an effect that was not seen in minimal medium. In addition, azo dye reduction studies with the ΔazoC knockout suggested the presence of additional functional azoreductases in this medically important bacterium. Overall, this study addresses a major gap in the literature by providing the first look, to our knowledge, at the complex physiology of C. perfringens upon azo dye exposure and the effect that both azo dyes and the azoreductase enzyme have on growth.

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Accountable Care Organizations (ACOs) are a promising new model for payment reform in the complex and fragmented health care system in the United States. Nursing vision and leadership are essential for the success of an organization participating in an ACO. By understanding the political, financial, and cultural facilitators and barriers to change, as well as models for helping organizations transition toward change (e.g., Kotter Model of Change Management), nurses have the potential to be leaders in health care change.

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MEMS micromirrors have proven to be very important optical devices with applications ranging from steerable mirrors for switches and cross-connects to spatial light modulators for correcting optical distortions. Usually beam steering and focusing are done with different MEMS devices and tilt angles in excess of 10 degrees are seldom obtained. Here we describe a single MEMS device that combines tip/tilt, piston mode and varifocal capability into a single, low cost device with very large tilt angles. Our device consists of a 400 micron diameter mirror driven with thermal bimorphs. We have demonstrated deflection angles of ± 40 degrees along both axes, a tunable focal length which varies between -0.48 mm to + 20.5 mm and a piston mode range of 300 microns - four separately controllable degrees of freedom in a single device. Potential applications range from smart lighting to optical switches and devices for telecom systems.

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Clostridium perfringens, a strictly anaerobic microorganism and inhabitant of the human intestine, has been shown to produce an azoreductase enzyme (AzoC), an NADH-dependent flavin oxidoreductase. This enzyme reduces azo dyes into aromatic amines, which can be carcinogenic. A significant amount of work has been completed on the activity of AzoC. Despite this, much is still unknown, including whether azoreduction of these dyes occurs intracellularly or extracellulary. A physiological study of C. perfringens involving the effect of azo dye exposure was completed to answer this question. Through exposure studies, azo dyes were found to cause cytoplasmic protein release, including AzoC, from C. perfringens in dividing and non-dividing cells. Sulfonation (negative charge) of azo dyes proved to be the key to facilitating protein release of AzoC and was found to be azo-dye-concentration-dependent. Additionally, AzoC was found to localize to the Gram-positive periplasmic region. Using a ΔazoC knockout mutant, the presence of additional azoreductases in C. perfringens was suggested. These results support the notion that the azoreduction of these dyes may occur extracellularly for the commensal C. perfringens in the intestine.

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Azoreductase enzymes present in many microorganisms exhibit the ability to reduce azo dyes, an abundant industrial pollutant, to produce carcinogenic metabolites that threaten human health. All biochemically-characterized azoreductases, around 30 to date, have been isolated from aerobic bacteria, except for AzoC, the azoreductase of Clostridium perfringens, which is from a strictly anaerobic bacterium. AzoC is a recently biochemically-characterized azoreductase. The lack of structural information on AzoC hinders the mechanistic understanding of this enzyme. In this paper, we report on the biophysical characterization of the structure and thermal stability of AzoC by using a wide range of biophysical tools: Liquid Chromatography-Mass Spectrometry (LC-MS), Circular Dichroism Spectroscopy, Fourier-transform Infrared (FTIR) Spectroscopy, SDS-PAGE, Size Exclusion Chromatography, MALDI-TOF and UV-visible spectroscopy. We found that the flavin cofactor of AzoC is FAD, while all other structurally-known azoreductases employ FMN as a cofactor. The secondary structure of AzoC has 16% less α-helix structures, 5% more ß-sheet structures and 11% more turn and unordered than the average of structurally-known azoreductase that have 10-14% sequence similarities with AzoC. We also found that oxidized AzoC is trimeric, which is unique amongst structurally known azoreductases. In contrast, reduced AzoC is monomeric, despite similarities in catalytic activity and thermal stability of oxidized and reduced AzoC. Our results show that the use of FTIR spectroscopy is crucial for characterization of the ß-sheet content in AzoC, illustrating the need for complementary biophysical tools for secondary structural characterization of proteins.

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The phosphatase and tensin homolog detected on chromosome 10 (PTEN) gene product modulates activation of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway. The PI3K pathway has been found to be involved in the regulation of the fragile X mental retardation protein, which is important for long-term depression and in the formation of new memories. We used delayed fear conditioning and trace fear conditioning to determine learning and memory deficits in neuron subset-specific Pten (NS-Pten) conditional knockout (KO) mice. We found that NS-Pten KO mice had deficits in contextual learning and trace conditioning, but did not have deficits in the ability to learn a conditioned stimulus. Furthermore, we found increased levels in the total and phosphorylated forms of the fragile X mental retardation protein (FMRP) in the hippocampus of NS-Pten KO mice.

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