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Distribution and orientation of 3-aminopropyltriethoxysilane (APTES) on a sensing surface play critical role on biosensor, but have not been fully investigated. In this work, the quality of APTES SAM immobilized on the Si(111) substrate was studied by observing sum frequency generation (SFG) response. The polarization, azimuthal angle, and position-dependent SFG spectra of APTES coverage were obtained. In ppp and psp-SFG spectra, the CH2 and CH3 vibrational and NH stretching modes were clearly seen around 3000 cm−1 and around 3300 cm−1 regions, respectively. The spp and ssp-SFG spectra presented too weak signals that the vibrational regions were not clear. The positional and azimuthal angle dependence of the SFG spectra was observed from 0o to 360o with the step of 45o rotation around the surface normal. The 0° is defined as the [(Formula presented.)] direction of Si(111) crystal lying in the incident plane and opposite to the incident k vectors. The appearance of the NH mode was observed to be strongly dependent on the position. The results indicate that the distribution and orientation of APTES molecules were not well ordered on the Si surfaces, suggesting that SFG is an efficient method to check the quality of APTES coverage immobilized on substrates.

Early detection and tracking of breast cancer treatment-related lymphedema have been helped by quantitative assessment methods and parameters, including bioelectrical impedance spectroscopy and tissue dielectric constant (TDC). Such measurements are evaluated with respect to interarm differences or ratios that (when exceeding specified thresholds) are suggestive of lymphedema. Specific threshold ratios depend on the assessment method and have been reported for arms. However, there is far less information available on thresholds to assess lymphedema that manifests in at-risk hands and essentially nothing known about TDC ratios in healthy hands. Such information is essential to establish reference values from which lymphedema threshold TDC values may be estimated. The specific aim of this research was to determine such interhand TDC ratios applicable to both young and mature women.A total of 70 women (35 under 30 years of age, YOUNG, and 35 over 50 years of age, MATURE) participated after signing an approved institutional review board informed consent. TDC values of the hand dorsum web were measured bilaterally in triplicate with participants in a supine resting position. Results showed MATURE TDC values to be about 15% less than YOUNG (p 0.01) on dominant and nondominant hands, but no statistical difference in dominant/nondominant interarm ratios (1.026 ± 0.100).Based on this data set's overall mean and two standard deviation value, an age-independent interhand TDC threshold ratio of 1.23 emerges as potentially useful for lymphedema detection. This is a good initial start threshold that is usable in future clinical and research assessments.

Background Intrahepatic cholestasis of pregnancy (ICP) is the most common liver disorder of pregnancy. It occurs when bile flow from the liver is obstructed, causing bile acid to accumulate. ICP usually presents with itching that lasts for the remainder of pregnancy. Untreated ICP has been shown to increase the incidence of adverse outcomes for the baby, including respiratory distress, meconium aspiration, neonatal intensive care unit hospitalization, and stillbirth. The probability of these events increases when bile acid levels are greater than 40 mmol/L. The current standard of care for ICP patients is a combination of ursodeoxycholic acid by mouth and early delivery, as the risk of stillbirth due to ICP increases in the last weeks of pregnancy. ICP has been linked to preeclampsia and gestational diabetes; studies have shown that the occurrence of both diseases is greater when the baby is male. The purpose of this study was to investigate if the occurrence, timing of diagnosis, peak bile acid levels, or severity of itching is dependent on the baby's sex in mothers who had ICP. Methods An online question-set (survey) was offered to women who had had ICP and were members of three different online support groups. Results A total of 1,502 women responded for a total of 2,289 documented ICP pregnancies, in which there were 1,059 female babies and 1,230 male babies. Based on chi-square analysis of differences in frequencies, no difference was found between pregnancies with male versus female babies regarding the occurrence, timing of diagnosis, peak bile acid levels, or severity of itching in the evaluated population. However, surprisingly, the findings revealed that first-trimester diagnosis of ICP was made in 5.6% of the pregnancies, and there were 30 (1.8%) cases of ICP diagnosed in the absence of itching. Conclusions The findings suggest that the baby's sex does not impact the occurrence, timing of diagnosis, peak bile acid levels, or itch severity in ICP. The findings that 5.6% of the ICP pregnancies in the present study were diagnosed in the first trimester and 1.8% were diagnosed without the presence of itching reinforce the need to investigate these less common presentations. More studies are needed to determine if these findings are consistent across other populations.

Background E-cigarette use, or vaping, is known to be associated with potentially life-threatening lung injury, with the Centers for Disease Control and Prevention reporting 2,807 hospitalizations and 68 deaths in the United States due to e-cigarette or vaping-associated lung injury. Vaping is also a risk factor for and is implicated in the spreading of COVID-19. Despite the consequences of vaping, the views and training of medical students regarding vaping is unclear. This study sought to investigate the knowledge and perception of vaping amongst future health care providers. Methods An anonymous, online survey was administered to 259 first through fourth year medical students at Nova Southeastern University Dr. Kiran C. Patel College of Osteopathic Medicine via a secure website link in October 2019 and January 2020. The survey consisted of two sections. All participants answered section one, involving nine questions. This first section addressed sociodemographic characteristics, personal views on vaping, rating and impact of vaping medical education, and whether students had ever tried vaping. If students had ever vaped, they proceeded to section two of the survey including nine additional questions. Students that reported no past vaping use ended the survey and did not proceed to section two. Section two focused on evaluating vaping habits of users by questioning age of first usage, use frequency and nature, reasons for first trying and/or continuing to use, plans for quitting, personal impact of use, and current use. Data was analyzed with frequency and percentage distributions. Results Most respondents were of age 18-25 years (66.8%) and female (60.2%). Almost all students (96.5%) were aware of the negative health consequences of vaping. More than two thirds of students (68.7%) rated their vaping medical education as inadequate and the majority (76.1%) indicated their medical school curriculum did not impact their view on the matter. Most students (71.0%) reported a more negative stance on vaping due to recent news and media. Of the respondents, over two thirds (37.5%) vaped at least once and were labeled "vapers." The most commonly stated reason for first trying vaping was recreational (60.8%). Half of vapers (50.5%) admitted to vaping in the past year and most vapers (90.6%) did not think their vaping impacted others. Current vaping use was reported in almost one-third of vapers (32.3%) despite knowing its dangers, and several (6.3%) did not consider vaping dangerous. Conclusion The findings from this pilot study conducted at a single medical school indicate possible deficiencies in vaping education, at least as perceived by the respondents and demonstrated by their vaping-related actions. It is unknown if the stated vaping views and practices of these medical students would be positively impacted by better vaping education or if these practices are generalizable to other students. However, the data suggests there is a need to consider more extensive analyses of medical school curriculums with respect to vaping education and training of students in these and related areas. Recommendations to enhance medical school curriculums include vaping-focused respiratory and gastrointestinal lectures, problem-based case studies on vaping, standardized patient encounters, and a community education program taught by medical students.

Background Based on prior reports of the use of magnets to treat pain, our goal was to determine if a concentric rare-earth alternating-pole magnet reduced period pain versus a sham-magnet. Methods Participants were females (N=36, 18 to 35 years) who regularly experienced menstrual period pain ≥ six on the numeric pain rating scale (NPRS) of 0-10. Subjects were excluded if they took pain medication on the study day or had implanted pacemakers/metallic devices or secondary dysmenorrhea. Participants were randomized to wear a concentric neodymium-iron boron active-magnet (surface-field of 0.4 Tesla) or a sham magnet. The participant and investigator applying the device were blinded to the device used. The device was placed at the abdominal location of the reported greatest pain for 40-minutes, during which time the subject was able to conduct the normal activity. Pain scores were reported prior to device wearing and afterward. Participants with post-treatment NPRS ratings reduced by ≥ 35% from their pretreatment pain ratings were scored as having reduced pain; reductions < 35% were scored as no meaningful pain change. The threshold of 35% was chosen based on a survey of 10 women as to the level of pain reduction they viewed as meaningful to them. Of the 36 women in this pilot study, 19 wore an active-magnet and 17 wore a sham-magnet. Analyses were based on chi-square and Mann-Whitney statistical tests. Results Pre-treatment pain scores (mean ± SD) were similar for both groups. Magnet-vs-sham pre-treatment scores were, respectively, 7.16 ± 0.85 vs. 6.94 ± 1.20 (p=0.330). Corresponding median values for the magnet (N=19) and sham (N=17) groups respectively were seven pre-treatment and four post-treatment vs. six pre-treatment and six post-treatment. Post-treatment scores for magnet treated subjects (4.16 ± 2.20) were significantly less (p=0.027) than for sham-treated (5.53 ± 1.50). Of the 19 who wore a magnet, 11 experienced meaningful pain-reduction, and eight did not. Of the 17 who wore a sham, three experienced meaningful pain-reduction, and 14 did not. Magnet and sham wearing responses were statistically significant via chi-square analysis (chi-square=6.12, p=0.013). Percentage reduction in pain score was 41.8% ± 31.1% for magnet-treated vs. 20.8% ± 16.1%, for sham-treated (p

This pilot study's goal was to investigate the impacts of static magnetic fields (SMF) on finger skin blood perfusion (SBP) when exposing the ulnar artery and ulnar and medial nerves to a rare earth concentric magnet for 30 minutes. Control SBP was measured in 4