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BACKGROUND: The gut-brain axis (GBA) plays a central role in cerebral ischaemia-reperfusion injury (CIRI). Rhubarb, known for its purgative properties, has demonstrated protective effects against CIRI. However, it remains unclear whether this protective effect is achieved through the regulation of the GBA. AIM: This study aims to investigate the mechanism by which rhubarb extract improves CIRI by modulating the GBA pathway. METHODS: We identified the active components of rhubarb extract using LC-MS/MS. The model of middle cerebral artery occlusion (MCAO) was established to evaluate the effect of rhubarb extract. We conducted 16S rDNA sequencing and untargeted metabolomics to analyze intestinal contents. Additionally, we employed HE staining, TUNEL staining, western blot, and ELISA to assess intestinal barrier integrity. We measured the levels of inflammatory cytokines in serum via ELISA. We also examined blood-brain barrier (BBB) integrity using Evans blue (EB) penetration, transmission electron microscopy (TEM), western blot, and ELISA. Neurological function scores and TTC staining were utilized to evaluate neurological outcomes. RESULTS: We identified twenty-six active components in rhubarb. Rhubarb extract enhanced α-diversity, reduced the abundance of Enterobacteriaceae, and partially rectified metabolic disorders in CIRI rats. It also ameliorated pathological changes, increased the expressions of ZO-1, Occludin, and Claudin 1 in the colon, and reduced levels of LPS and d-lac in serum. Furthermore, it lowered the levels of IL-1ß, IL-6, IL-10, IL-17, and TNF-α in serum. Rhubarb extract mitigated BBB dysfunction, as evidenced by reduced EB penetration and improved hippocampal microstructure. It upregulated the expressions of ZO-1, Occludin, Claudin 1, while downregulating the expressions of TLR4, MyD88, and NF-κB. Similarly, rhubarb extract decreased the levels of IL-1ß, IL-6, and TNF-α in the hippocampus. Ultimately, it reduced neurological function scores and cerebral infarct volume. CONCLUSION: Rhubarb effectively treats CIRI, potentially by inhibiting harmful bacteria, correcting metabolic disorders, repairing intestinal barrier function, alleviating BBB dysfunction, and ultimately improving neurological outcomes.

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There is an increasing market share of dealcoholized wines due to rise in patronage by wine consumers. However, the aroma of such wines deteriorates the more the alcohol content is reduced. Improving the aroma with edible flowers may curb this problem. To improve the aroma of a dealcoholized Merlot red wine, extracts of peach, rose, and lily flowers (FEs) were added to develop three reconstituted dealcoholized wines (RDWS). RDWS were compared with the original wine and the dealcoholized wine (DW) based on chemical properties, aroma compounds, and sensory characteristics. The FEs had no effect on the chemical parameters of RDWS. The FEs improved the volatile composition of RDWS, especially ethyl octanoate, isoamyl octanoate, linalool, and geraniol. Sensory analysis showed that aroma intensity and fruity and floral notes improved in RDWS compared to DW. Among the FEs, rose was the best and can improve the aroma of dealcoholized Merlot red wine.

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This paper presents a 14-b 20-MS/s energy-efficient SAR ADC in 65-nm CMOS technology for portable medical ultrasound systems. To break the limitation of the ADC linearity on the DAC size in a SAR ADC, a background mismatch calibration technique is employed. As a result, the thermal noise will be the major constraint for the DAC size. In addition, a compact noise-reduction technique is proposed to alleviate the adverse impact of the input-referred comparator noise on the effective resolution. Moreover, a 2.5-V on-chip LDO, which serves as the reference generator for the ADC core, is also integrated to guarantee the reference accuracy and to suppress the supply noise. To reduce the capacitive load of the comparator and boost the comparison speed, a low fan-in SAR logic is also designed. With the proposed mismatch calibration technique and the noise-reduction technique activated, measured results indicate that the peak signal-to-noise-and-distortion ratio (SNDR) and the spurious-free dynamic range (SFDR) achieve 78.8 dB and 95.4 dB, respectively. At 20 MS/s, the ADC consumes 6.8mW from its 1.2 V/3.3V supplies in total, leading to an SNDR-based Schreier FOM of 170.5 dB at Nyquist. The active area of the ADC is 450 × 540µm2.

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Over the last few years, the dealcoholization of wine has piqued the interest of winemakers and researchers. Physical dealcoholization methods are increasingly used in the dealcoholization of wines because they can partially or completely reduce the alcohol content of wines. This study aimed to compare the chemical parameters, volatile composition and sensory quality of white, rosé and red wines dealcoholized by two physical dealcoholization methods: reverse osmosis (RO) and vacuum distillation (VD) at 0.7% v/v ethanol. RO and VD effectively reduced the ethanol concentration in all wines to the required 0.7% v/v, but also significantly affected most chemical parameters. The pH, free sulfur dioxide, total sulfur dioxide, and volatile acidity decreased significantly due to dealcoholization by RO and VD, while reducing sugars and total acidity increased significantly. VD resulted in higher color intensity, which was perceptible in dealcoholized rosé and red wines, while RO caused notable color differences in dealcoholized white and red wine fractions. RO were richer in esters (more ethyl esters and isoamyl acetate), higher alcohols, organic acids, terpenics and C13-norisoprenoids, and carbonyl compounds, while wines dealcoholized with VD had lower levels of these volatile compounds, which may reflect both the loss of esters into the distillate during evaporation and condensation (in the case of VD) and a shift in the chemical equilibrium responsible for ester formation and hydrolysis after ethanol removal. ß-damascenone exhibited the highest OAV in all wines, however, losses equal to 35.54-61.98% in RO dealcoholized fractions and 93.62% to 97.39% in VD dealcoholized fractions were observed compared to the control wines. The predominant aroma series in the original and dealcoholized wines were fruity and floral but were greatly affected by VD. Sensory evaluation and PCA showed that dealcoholization by RO improved the fruity and floral notes (in rosé and red wines), color intensity, sweetness, viscosity, and aroma intensity better than dealcoholization by VD, while VD mainly enhanced the color of the dealcoholized wines. Both methods increased the acidity of the respective dealcoholized wines. Nevertheless, RO dealcoholized wines achieved higher acceptance by the panelists than VD dealcoholized wines. Therefore, RO may be a better method for producing dealcoholized (0.7% v/v) wines with minimal impact on aroma and sensory quality.

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BACKGROUND: One of the front treatment regimens used for metastatic triple-negative breast cancer (mTNBC) is treatment with programmed death-1 (PD-1) or programmed death ligand-1 (PD-L1) blockade combine with chemotherapy. However, the results of such studies have been controversial. METHODS: A systematic searched of PubMed, Embase, Cochrane Library, and the proceedings of the last 5 years of several meetings until February 18, 2021. The primary endpoint was the progression-free survival (PFS) of PD-L1-positive patients treated with PD1/PD-L1 blockade plus chemotherapy compare with chemotherapy. RESULTS: Overall, 4 studies that included a total of 3007 mTNBC patients were analyzed in this meta-analysis. PFS was significantly improved in the PD1/PD-L1 blockade plus chemotherapy group compared with the chemotherapy group in PD-L1-positive mTNBC patients (hazard ratios, (HR), 0.69; 95% CI, 0.59-0.80; P < .001), also in intention-to-treat (ITT) population (HR, 0.82; 95% CI, 0.74-0.90; P < .001). However, no significant benefit in overall survival (OS) was observed regardless of PD-L1 status or ITT population. The immunotherapy plus chemotherapy has higher adverse events (AEs) compared with chemotherapy (all AEs, Odds ratios (ORs), 2.33; 95% CI, 1.50-3.62; P < .001; grade 3-5 AEs, OR, 1.27; 95% CI, 1.04-1.55; P = .019). CONCLUSIONS: This meta-analysis showed that the addition of PD1/PD-L1 blockade to chemotherapy improved PFS in PD-L1 positive mTNBC patients, also in the ITT population. However, no significant benefit in OS was observed in patients of PD-L1 positive or in the ITT population after adding PD1/PD-L1 blockade. We found a higher rate of AEs with the addition of PD1/PD-L1 blockers to chemotherapy.

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Background: Early-onset Parkinson's disease (EOPD) is one uncommon Parkinson's disease subtype with characteristic clinicopathological features. The full epigenomic profile of EOPD is largely unknown. Methods: We performed the first study to investigate the EOPD full methylation profile of cerebrospinal fluid (CSF) cell-free DNA (cfDNA) from 26 EOPD patients and 10 control patients. Results: 2220 differentially methylated genes were identified in EOPD. Hypermethylation far outweighed hypomethylation in gene numbers. Clustering and enrichment analyses identified aberrant neuronal function and immune response. Weighted correlation network analysis demonstrated significant correlation between methylation signatures and clock drawing test (CDT), mini-mental state examination (MMSE), education, working status, alcohol drinking history and Hamilton anxiety scale (HAMA). Several key networking genes in EOPD aberrant methylation were also identified. Conclusions: The methylation profile and signatures of CSF cfDNA were revealed for the first time in EOPD. Aberrant methylation signatures were correlated with education, working status, alcohol drinking history, CDT, MMSE and HAMA.

Lay abstract Early-onset Parkinson's disease (EOPD), a progressive disease of the nervous system marked by tremor, muscular rigidity and slow and imprecise movement, is generally found in people under the age of 40 years. In this study, we performed methylation test on cerebrospinal fluid (CSF). The test showed that specific CSF methylation profiles could be used to help EOPD diagnosis. A subset of differentially methylated genes were also identified, which could also be used as markers for EOPD diagnosis. In future, we will validate the methylation test in blood and try to find blood-based diagnostic markers to facilitate the diagnosis of EOPD by a single blood draw.

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Glycosylation is a key cellular mechanism that regulates several physiological and pathological functions. Therefore, identification and characterization of specific-protein glycosylation in vivo are highly desirable for studying glycosylation-related pathology and developing personalized theranostic modalities. Herein, we demonstrated a photoacoustic (PA) nanoprobe based on the proximity-induced hybridization chain reaction (HCR) for amplified visual detection of protein-specific glycosylation in vivo. Two kinds of functional DNA probes were designed. A glycan probe (DBCO-GP) was attached to glycans through metabolic oligosaccharide engineering (MOE) and protein probe (PP)-targeted proteins by aptamer recognition. Proximity-induced hybridization of the complementary domain between the two kinds of probes promoted conformational changes in the protein probes and in situ release of the HCR initiator domain. Gold nanoparticles (AuNPs) modified by complementary sequences (Au-H1 and Au-H2) self-assembled into Au aggregates via the HCR, thereby converting DNA signals to photoacoustic signals. Due to the high contrast and deep penetration of photoacoustic imaging, this strategy enabled in situ detection of Mucin 1 (MUC1)-specific glycosylation in mice with breast cancer and successfully monitored its dynamic states during tunicamycin treatment. This imaging technique provides a powerful platform for studying the effects of glycosylation on the protein structure and function, which helps to elucidate its role in disease processes.

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Rhubarb anthraquinone glycosides (RAGs) have been proven to have significant therapeutic effects on ischemic stroke, and this effect may be related to the microbiome-gut-brain axis. In this study, an HPLC-FLD method was established to measure brain-gut neurotransmitters of rats with cerebral ischemia-reperfusion injury (CIRI), to explore whether the mechanism of RAGs against CIRI is related to the microbiome-gut-brain axis. A Shimadzu ODS-3 C18 column was used for chromatographic separation, and 5-hydroxytryptamine (5-HT), 5-hydroxy indole acetic acid (5-HIAA), glutamic acid (Glu), aspartic acid (Asp), and γ-aminobutyric acid (GABA) were determined simultaneously. The results showed that there is an excellent linear relationship (R2 ≥ 0.9990) and a high separation degree in the HPLC-FLD method. Whereas the contents of Asp and Glu in the brain and colon increased (p < 0.05), the contents of 5-HT, 5-HIAA, and GABA in the brain and colon decreased (p < 0.05) after CIRI. RAGs could effectively reduce the contents of Asp and Glu (p < 0.05), and increase the contents of 5-HT, 5-HIAA, and GABA in the brain and colon (p < 0.05). Combined with the previous experimental results, we can speculate that RAGs can regulate intestinal flora disorder caused by CIRI, and then regulate the imbalance between the release and decomposition of neurotransmitters caused by intestinal flora disorder.

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Compared with semiconductor quantum dots and organic chromophores, carbon dots (CDs)-based lysosome probe with strong emission, an intrinsic targeting ability, and easy synthesis procedure were urgently desired in visualization imaging studies. Herein, we showed that it was possible to produce CDs with the desired properties for lysosome imaging via a one-step hydrothermal treatment of commercial reagents, rose bengal (RB) and branched polyethylenimine (bPEI). The prepared bPEI-RB CDs (P-R CDs) had a high fluorescence quantum yield (FLQY) of 90.49%, a narrow emission band of 30 nm, negligible phototoxicity, and dark toxicity. Moreover, P-R CDs had an intrinsic lysosome targeting ability without any postmodification of the ligands. Long-term cell imaging displayed P-R CDs can anchor lysosomes for up to 48 h without leakage. In addition, experimental results confirmed that dehalogenation cross-linking and structural reorganization of the reactants were the main causes of the ultrahigh photoluminescence efficiency, low cytotoxicity, and passivated surface of the P-R CDs. This origin was attributed to the restricted intersystem crossing and nonradiative transition, the reduced production of singlet oxygen, and suitable -NH2 functional groups. Due to outstanding characteristics, P-R CDs may be developed for a promising tool in lysosome images. The concept of facile preparation will also pave a new avenue for developing ultrabright functional nanomaterial markers.

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The topographic projection of afferent terminals into two-dimensional maps is essential for sensory systems to encode the locations of sensory stimuli. In vertebrates, guidance cues are critical for establishing a coarse topographic map, while neuronal activity directs fine-scale topography between adjacent afferent terminals. However, the molecular mechanism underlying activity-dependent fine-scale topography is not well known. Studies in the Drosophila visual system have demonstrated that cell-adhesion molecules direct fine-scale topography, but whether or not these molecules are involved in activity-dependent fine-scale topography remains to be determined. We previously reported that the nociceptors in Drosophila larvae form an activity-dependent fine-scale topographic system. The establishment of this system is instructed by the level of neuronal activity in individual nociceptors. Here, we show that the atypical cadherin Flamingo (Fmi) is required for establishing the nociceptor topographic map. We found that the topographic defect caused by loss of fmi was epistatic to the inhibition of neuronal activity and the overexpression of the activity-regulated gene Trim9. These results suggest that Fmi and neuronal activity interact to regulate fine-scale topography. This study provides a link between neuronal activity and the cell-adhesion molecule in the establishment of fine-scale topography.

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BACKGROUND: Chemical exchange saturation transfer (CEST) MRI requires the acquisition of multiple saturation-weighted images and can last several minutes. Misalignments among these images, which are often due to the inevitable motion of the subject, will corrupt CEST contrast maps and result in large quantification errors. Therefore, the registration of the CEST series is critical. However, registration is challenging since common intensity-based registration algorithms may fail to differentiate CEST signals from motion artifacts. Herein, we studied how different patterns of motion affect CEST quantification and proposed a cascaded two-step registration scheme by utilizing features extracted from the entire Z-spectral image series instead of direct registration to a single image. METHODS: The proposed approach is conducted in two stages: during the first coarse registration, the Z-spectral image series is decomposed by robust principal component analysis (RPCA) to separate CEST contrast from motion. The recomposed image series using only the low-rank component, which contains minimized motion, are averaged to generate a reference for the alignment of the image series. To further remove residual misalignments, the coarse registration is followed by a refinement stage, which uses PCA iteratively to generate motionless synthetic reference series with the first few principal components (PCs) that correspond to CEST contrast. In the end, the quality check is performed to exclude the images with unsuccessful registration. RESULTS: The proposed registration scheme (RPCA + PCA_R) was assessed by both phantom experiments and in vivo data of tumor-bearing mouse brain, with simulated random rigid motion in different patterns applied to the acquired static Z-spectral image series. For comparison, previous correction schemes using an explicit image [either S0 or Ssat(∆ω)] as registration reference were also performed, named as S0_R and Ssat_R respectively. To illustrate the advantage of combination of RPCA and PCA, registration was also exploited using either only the RPCA-based method (RPCA_R) or only the PCA-based one (PCA_R). Compared with the above four methods, RPCA + PCA_R allowed for more accurate correction of the corrupted Z-spectral images, exhibiting smaller MTRasym(∆ω) error maps and lower residual Z-spectra referring to the static data. Among all the five correction methods, the corrected Z-spectral image series by RPCA + PCA_R and the resulting MTRasym(∆ω) maps achieved the highest correlation coefficients (CC) with respect to the static ones. CONCLUSIONS: The registration scheme of RPCA + PCA_R provides robust motion correction between two specific Z-spectral images and among an entire image series, through extraction of the static component from the entire Z-spectra set and inclusion of a PCA-based refinement step. Therefore, this method can help improve CEST acquisition and quantification.

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BACKGROUND: Chemical exchange saturation transfer (CEST) MRI is a promising approach for detecting biochemical alterations in cancers and neurological diseases, but the quantification can be challenging. Among numerous quantification methods, Lorentzian difference (LD) is relatively simple and widely used, which employs Lorentzian line-shape as a reference to describe the direct saturation (DS) of water and takes account of difference against experimental CEST spectra data. However, LD often overestimates CEST and nuclear overhauser enhancement (NOE) effects. Specifically, for fast-exchanging CEST species require higher saturation power (B1_sat) or in the presence of strong magnetization transfer (MT) contrast, Z-spectrum appears more like a Gaussian line-shape rather than a Lorentzian line-shape. METHODS: To improve the conventional LD analysis, the present study developed and validated a novel fitting algorithm through a linear combination of Gaussian and Lorentzian function as the reference spectra, namely, Voxel-wise Optimization of Pseudo Voigt Profile (VOPVP). The experimental Z-spectra were pre-fitted with Gaussian and Lorentzian method independently, in order to determine Lorentzian proportionality coefficient (a). To further compensate for the line-shape changes under different B1_sat's, a B1-dependent adjustment was applied to the experimental Z-spectra (Z_exp) according to the prior knowledge learned from 5-pool Bloch equation-based simulations at a range of B1_sat's. Then, the obtained Z-spectra (Z_B1adj) was fitted by the previously defined VOPVP function. Considering the asymmetric component of MT, the positive- and negative-side of Z-spectra were fitted separately, while the middle part (-0.6 to 0.6 ppm, consisted primarily of DS) was fitted using Lorentzian function. Finally, the difference between Z_VOPVP and Z_exp was defined as the CEST and NOE contrast. To validate our VOPVP method, an extensive simulation of CEST Z-spectra was performed using 5-pool model and 6-pool model with greater MT component. RESULTS: In comparison with LD approach, VOPVP exhibited lower sum of squares due to error (SSE) and higher goodness of fit (R-square) for the experimental Z-spectra at all B1_sat. Moreover, the results indicated that VOPVP fitting improved the overestimated contributions from amide proton transfer (APT) and NOE through LD at all B1_sat. Despite that the relationship for B1-dependent adjustment was pre-determined using a single 5-pool model, the VOPVP fittings obtained accurate quantification for multiple 6-pool models with a range of T1w's and T2w's. The robustness of VOPVP fitting was also proved by simulations using 3T parameters. Furthermore, we assessed VOPVP in vivo in a glioblastoma-bearing mouse. Compared to LD maps, VOPVP quantification maps displayed higher contrast-to-noise ratio between tumor and normal contralateral tissue for APT, glutamate and nuclear overhauser effect (NOE), when B1_sat >1 µT. CONCLUSIONS: As an improvement of LD method, VOPVP fitting can serve as a simple, robust and more accurate approach for quantifying CEST and NOE contrast.

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Human-robot interaction (HRI) will soon transform and shift the communication landscape such that people exchange messages with robots. However, successful HRI requires people to trust robots, and, in turn, the trust affects the interaction. Although prior research has examined the determinants of human-robot trust (HRT) during HRI, no research has examined the messages that people received before interacting with robots and their effect on HRT. We conceptualize these messages as SMART (Strategic Messages Affecting Robot Trust). Moreover, we posit that SMART can ultimately affect actual HRI outcomes (i.e., robot evaluations, robot credibility, participant mood) by affording the persuasive influences from user-generated content (UGC) on participatory Web sites. In Study 1, participants were assigned to one of two conditions (UGC/control) in an original experiment of HRT. Compared with the control (descriptive information only), results showed that UGC moderated the correlation between HRT and interaction outcomes in a positive direction (average Δr = +0.39) for robots as media and robots as tools. In Study 2, we explored the effect of robot-generated content but did not find similar moderation effects. These findings point to an important empirical potential to employ SMART in future robot deployment.

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The current research examines the persuasive effects of reciprocity in the context of human-robot interaction. This is an important theoretical and practical extension of persuasive robotics by testing (1) if robots can utilize verbal requests and (2) if robots can utilize persuasive mechanisms (e.g., reciprocity) to gain human compliance. Participants played a trivia game with a robot teammate. The ostensibly autonomous robot helped (or failed to help) the participants by providing the correct (vs. incorrect) trivia answers. Then, the robot directly asked participants to complete a 15-minute task for pattern recognition. Compared to no help, results showed that a robot's prior helping behavior significantly increased the likelihood of compliance (60 percent vs. 33 percent). Interestingly, participants' evaluations toward the robot (i.e., competence, warmth, and trustworthiness) did not predict compliance. These results also provided an insightful comparison showing that participants complied at similar rates with the robot and with computer agents. This result documents a clear empirically powerful potential for the role of verbal messages in persuasive robotics.

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Cutaneous pili migrans and creeping eruption caused by parasitic diseases may present as a moving linear lesion in skin. The former, caused by a hair shaft or fragment embedded in the superficial skin or middle dermis, is a rare condition characterized by creeping eruption with a black line observed at the advancing end. In exceptionally rare instance, the hair grows inside the skin and burrows in the uppermost dermis, such a condition has been called "ingrown hair."We report a 30-year-old Chinese man, who was accustomed to pull or extrude the beard hairs, with 1-year history of slowly extending black linear eruption on his right chin. Cutaneous examination revealed a 4-cm long black linear lesion beneath the skin associated with edematous erythema around and folliculitis on both ends of the lesion. After treatment with topical mupirocin ointment, the erythema and folliculitis improved and 2 hairs of the beard with hair follicles were pulled out from the skin. Two weeks later, another similar black line about 1 cm in length in the skin presented on the prior lesional area, which was pulled out by a shallow incision of the skin and was also demonstrated as a beard hair with hair follicle.The patient was diagnosed as "ingrowing hair" with multiple recurrences. The lesions recovered after the beard hairs were pulled out. No recurrence occurred in a year of follow-up.We suggest that "ingrowing hair" is better than "ingrown hair" to describe such a condition. Pulling out the involved hair and correcting the bad practice are its optimal management strategies.

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OBJECTIVE: To investigate the hematological and molecular characteristics of hemoglobin Q-Thailand in Guangxi, so as to provide reference data for hemoglobinopathy screening. METHODS: A total of 51088 samples were screened by capillary electrophoresis. Samples suspected with Hb Q-Thailand were processed with blood cell count and DNA sequencing. Gap-PCR and PCR-reverse dot blotting were used for the detection of common mutations of alpha and beta thalassemia. RESULTS: The carrier rate of Hb Q-Thailand in Guangxi was 0.06%. The hematological phenotype index(HGB, MCV, MCH, Hb Q-Thailand, Hb A2, Hb QA2) of 28 Hb Q-Thailand heterozygous samples were (125.60±22.30) g/L, (78.22±4.81) fl, (25.79±2.14) pg, (27.37±2.72)%, (1.89±0.22)%, (0.69±0.16)%, respectively, and of 2 Hb Q-Thailand heterozygous combined with beta-thalassemia samples were (125.00±18.39) g/L, (69.65±5.02) fl, (22.00±0.0) pg, (14.80±0.71)%, (4.45±0.07)%, (0.95±0.71)%, respectively. A statistical difference was found in hematological phenotype index between the two groups except HGB (P<0.05). CONCLUSION: In Guangxi, the detected Hb Q-Thailands were mainly heterozygous. Part of Hb Q-Thailand heterozygotes had normal red blood cell parameters, but can still be detected by hemoglobin electrophoresis. When combined with other types of thalassemia, these heterozygotes may still exhibit reduced MCV and MCH or various degrees of anemia.

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The effort to increase Web organ donation registrations in Michigan by enhancing 2 types of university campaigns with social media strategies informed by social identity theory is the focus of this research. The two campaigns focused on either ingroup or rivalry outgroup social identification, and each was enhanced with individually focused social media in the first year of the campaign and with electronic word of mouth in Year 2 of the campaign. Results indicated that individually focused social media such as Facebook ads worked well in rivalry campaigns (in which registrations increased two times over baseline) but not in ingroup identification campaigns (in which registrations decreased significantly over baseline when ads were introduced in the first year of each type of campaign). Electronic word-of-mouth strategies worked well in both ingroup identification campaigns (in which registrations increased two times over baseline) and rivalry campaigns (in which registrations rose almost eight times over baseline, when strategies were introduced in the second year of each type of campaign).

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Individuals often apply social rules when they interact with computers, and this is known as the Computers Are Social Actors (CASA) effect. Following previous work, one approach to understand the mechanism responsible for CASA is to utilize computer agents and have the agents attempt to gain human compliance (e.g., completing a pattern recognition task). The current study focuses on three key factors frequently cited to influence traditional notions of compliance: evaluations toward the source (competence and warmth), normative influence (reciprocity), and affective influence (mood). Structural equation modeling assessed the effects of these factors on human compliance with computer request. The final model shows that norm-based influence (reciprocity) increased the likelihood of compliance, while evaluations toward the computer agent did not significantly influence compliance.

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BACKGROUND AND OBJECTIVES: The purpose of this paper is to report on the development and implementation of a learning competency assessment survey for first-year medical students. We began by defining learning competencies in a manner that is parallel to the clinical competencies resulting in a self-assessment survey of 1,998 first-year osteopathic medical students from 25 osteopathic medical schools. Results from the online survey indicated that the internal structure of the instrument and the reliability of the items were strong. The survey revealed that first-year medical students were most confident in their ability to perform in a professional manner and least confident in their ability to manage their curriculum, particularly with the assistance of faculty and advisors. A regression analysis indicated that the best predictors of curricular involvement were Student Learning and Improvement, Knowledge of Osteopathic Philosophy and Skills, Interpersonal Communication, and Systems Knowledge. However, Medical Knowledge and Professionalism did not provide any unique variance to the model, suggesting that students' confidence in their undergraduate science training or self perceptions of their professionalism had little to do with their confidence in navigating medical school.

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