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1.
Nanoscale Horiz ; 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39023125

ABSTRACT

Partially reduced forms of titanium dioxide (sometimes called "black" titania) have attracted widespread interest as promising photocatalysts of oxidation due to their absorption in the visible region. The main approaches to produce it rely on postprocessing at high temperatures (up to 800 °C) and high pressures (up to 40 bar) or on highly reactive precursors (e.g., TiH2), and yield powders with poorly controlled sizes, shapes, defect concentrations and distributions. We describe an approach for the one-step synthesis of TiO2 colloidal nanocrystals at atmospheric pressure and temperatures as low as 280 °C. The temperature of the reaction allows the density of oxygen vacancies to be controlled by nearly two orders of magnitude independently of their size, shape, or colloidal stability. This synthetic pathway appears to produce vacancies that are homogeneously distributed in the nanocrystals, rather than being concentrated in an amorphous shell. As a result, the defects are protected from oxidation and result in stable optical properties in oxidizing environments.

2.
J Dent Sci ; 19(3): 1461-1468, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39035326

ABSTRACT

Background/purpose: Taiwan's dentistry entered into a new era of modernization and flourished during the Japanese colonial period. However, we know very little about the composition of dentists at that time. This study attempted to analyze the ethnicity, gender, and geographical distribution of dentists in Taiwan in 1939 (Showa 14). Materials and methods: The methods of documentary analysis and secondary data analysis were adopted to find the composition of dentists during the late Japanese colonial period through a name list of contract dentists for the Postal Savings Insurance published in August 1939 (Showa 14) by the Taiwan Government Transportation Department Information Bureau. Results: The total number of contract dentists was 368, accounting for 86.79% of the 424 practicing dentists in Taiwan in 1939 (Showa 14). Of the 368 contract dentists (328 males and 40 females), 225 (61.14%) were Taiwanese and 143 (38.86%) were Japanese. Among the 8 prefectures in Taiwan, Tainan Prefecture had the largest number of dentists (97), followed by Taipei (84) and Taichung (78) prefectures. The number of contract dentists per 100,000 people was 6.24, equivalent to 16,021 people served by each contract dentist in 1939 (Showa 14). The chi-square test for the trend analysis of gender distribution indicated a significantly higher proportion of male than female contract dentists in either Taiwanese or Japanese ethnic group. Conclusion: In the late Japanese colonial period, the number of Taiwanese dentists exceeded that of Japanese dentists. Furthermore, there were more male than female dentists in either the Taiwanese or the Japanese population.

3.
Nanoscale ; 16(27): 12735-12749, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38913069

ABSTRACT

This review summarizes the work on the use of plasmas to post-process nanostructures, in particular colloidal nanocrystals, as promising candidates for applications of heterogeneous catalysis. Using plasma to clean or modify the surface of nanostructures is a more precisely controlled method compared to other conventional methods, which is preferable when strict requirements for nanostructure morphology or chemical composition are necessary. The ability of plasma post-processing to create mesoporous materials with high surface areas and controlled microstructure, surfaces, and interfaces has transformational potential in catalysis and other applications that leverage surface/interface processes.

4.
J Dent Sci ; 19(2): 1075-1082, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38618089

ABSTRACT

Background/purpose: Dental pulp stem cells (DPSCs) exhibit versatile differentiation capabilities, including neural differentiation, prompting the hypothesis that they may be implicated in the neurodevelopment of teeth. This study aimed to explore the temporospatial dynamics between DPSCs and tooth innervation, employing immunofluorescence staining and fluorescent dye injections to investigate the distribution of DPSCs, neural stem cells (NSCs), nerve growth cones, and sensory nerves in developing mouse tooth germs at various stages. Materials and methods: Immunofluorescence staining targeting CD146, Nestin, and GAP-43, along with the injection of AM1-43 fluorescent dye, were utilized to observe the distribution of DPSCs, NSCs, nerve growth cones, and sensory nerves in mouse tooth germs at different developmental stages. Results: Positive CD146 immunostaining was observed in microvascular endothelial cells and pericytes within and around the tooth germ. The percentage of CD146-positive cells remained consistent between 4-day-old and 8-day-old second molar tooth germs. Conversely, Nestin expression in odontoblasts and their processes decreased in 8-day-old tooth germs compared to 4-day-old ones. Positive immunostaining for GAP-43 and AM1-43 fluorescence revealed the entry of nerve growth cones and sensory nerves into the pulp in 8-day-old tooth germs, while these elements were confined to the dental follicle in 4-day-old germs. No co-localization of CD146-positive DPSCs with nerve growth cones and sensory nerves was observed. Conclusion: DPSCs and NSCs were present in dental pulp tissue before nerves penetrated the pulp. The decline in NSCs after nerve entry suggests a potential role for DPSCs and NSCs in attracting neural growth and/or differentiation within the pulp.

6.
J Clin Transl Endocrinol ; 35: 100336, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38545460

ABSTRACT

Background: Post-operative fluid restriction after transsphenoidal surgery (TSS) for pituitary tumors may effectively prevent delayed hyponatremia, the most common cause of readmission. However, implementation of individualized fluid restriction interventions after discharge is often complex and poses challenges for provider and patient. The purpose of this study was to understand the factors necessary for successful implementation of fluid restriction and discharge care protocols following TSS. Methods: Semi-structured interviews with fifteen patients and four caregivers on fluid discharge protocols were conducted following TSS. Patients and caregivers who had surgery before and after the implementation of updated discharge protocols were interviewed. Data were analyzed inductively using a procedure informed by rapid and thematic analysis. Results: Most patients and caregivers perceived fluid restriction protocols as acceptable and feasible when indicated. Facilitators to the protocols included clear communication about the purpose of and strategies for fluid restriction, access to the care team, and involvement of patients' caregivers in care discussions. Barriers included patient confusion about differences in the care plan between teams, physical discomfort of fluid restriction, increased burden of tracking fluids during recovery, and lack of clarity surrounding desmopressin prescriptions. Conclusion: Outpatient fluid restriction protocols are a feasible intervention following pituitary surgery but requires frequent patient communication and education. This evaluation highlights the importance of patient engagement and feedback to effectively develop and implement complex clinical interventions.

7.
Laryngoscope ; 134(7): 3136-3142, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38334225

ABSTRACT

OBJECTIVES: To understand attentional preferences for normal and microtia ears. METHODS: Eye-tracking technology was used to characterize gaze preferences. A total of 71 participants viewed images of 5 patients with unilateral microtia. Profile images of patient faces and isolated ears including normal, microtia, and post-reconstruction microtia ears were shown. Total time of fixation in predefined areas of interest (AOI) was measured. Inferential statistics were used to assess significance of fixation differences between AOIs within and between facial or auricular features. RESULTS: The ear received most visual attention in lateral view of the face (1.91 s, 1.66-2.16 s) [mean, 95% CI], followed by features of the "central triangle"-the eyes (1.26 s, 1.06-1.46), nose (0.48 s, 0.38-0.58), and mouth (0.15 s, 0.15-0.20). In frontal view, microtia ears received less attention following surgical reconstruction (0.74 s vs. 0.4 s, p < 0.001). The concha was the most attended feature for both normal (2.97 s, 2.7-3.23) and reconstructed microtia ears (1.87 s, 1.61-2.13). Scars on reconstructed ears altered the typical visual scanpath. CONCLUSION: The ear is an attentional gaze landmark of the face. Attention to microtia ears, both pre- and post-reconstruction, differs from gaze patterns of normal ears. The concha was the most attended to subunit of the ear. Attentional gaze may provide an unbiased method to determine what is important in reconstructive surgery. LEVEL OF EVIDENCE: NA Laryngoscope, 134:3136-3142, 2024.


Subject(s)
Congenital Microtia , Fixation, Ocular , Plastic Surgery Procedures , Humans , Congenital Microtia/surgery , Male , Female , Plastic Surgery Procedures/methods , Fixation, Ocular/physiology , Eye-Tracking Technology , Adult , Adolescent , Young Adult , Attention/physiology , Child
10.
J Dent Sci ; 19(1): 663-665, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38303826
12.
Alzheimers Res Ther ; 16(1): 25, 2024 02 02.
Article in English | MEDLINE | ID: mdl-38308344

ABSTRACT

BACKGROUND: Secondary prevention clinical trials for Alzheimer's disease (AD) target amyloid accumulation in asymptomatic, amyloid-positive individuals, but it is unclear to what extent other pathophysiological processes, such as small vessel cerebrovascular disease, account for participant performance on the primary cognitive outcomes in those trials. White matter hyperintensities are areas of increased signal on T2-weighted magnetic resonance imaging (MRI) that reflect small vessel cerebrovascular disease. They are associated with cognitive functioning in older adults and with clinical presentation and course of AD, particularly when distributed in posterior brain regions. The purpose of this study was to examine to what degree regional WMH volume is associated with performance on the primary cognitive outcome measure in the Anti-Amyloid Treatment in Asymptomatic Alzheimer's Disease (A4) study, a secondary prevention trial. METHODS: Data from 1791 participants (59.5% women, mean age (SD) 71.6 (4.74)) in the A4 study and the Longitudinal Evaluation of Amyloid Risk and Neurodegeneration (LEARN) companion study at the screening visit were used to quantify WMH volumes on T2-weighted fluid-attenuated inversion recovery (FLAIR) MR images. Cognition was assessed with the preclinical Alzheimer cognitive composite (PACC). We tested the association of total and regional WMH volumes with PACC performance, adjusting for age, education, and amyloid positivity status, with general linear models. We also considered interactions between WMH and amyloid positivity status. RESULTS: Increased frontal and parietal lobe WMH volume was associated with poorer performance on the PACC. While amyloid positivity was also associated with lower cognitive test scores, WMH volumes did not interact with amyloid positivity status. CONCLUSION: These results highlight the potential of small vessel cerebrovascular disease to drive AD-related cognitive profiles. Measures of small vessel cerebrovascular disease should be considered when evaluating outcome in trials, both as potential effect modifiers and as a possible target for intervention or prevention.


Subject(s)
Alzheimer Disease , Cerebrovascular Disorders , Cognitive Dysfunction , White Matter , Aged , Female , Humans , Male , Alzheimer Disease/complications , Alzheimer Disease/diagnostic imaging , Brain/pathology , Cerebrovascular Disorders/complications , Cerebrovascular Disorders/diagnostic imaging , Cerebrovascular Disorders/pathology , Cognition , Cognitive Dysfunction/pathology , Magnetic Resonance Imaging , Prospective Studies , White Matter/pathology , Clinical Trials as Topic
13.
Laryngoscope ; 134(3): 1431-1436, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37610281

ABSTRACT

OBJECTIVE: To assess the risk of aspiration associated with post-swallow residue subsites in Fiberoptic Endoscopic Evaluation of Swallowing (FEES) in bottle-fed infants <1 year of age. METHODS: This is a retrospective matched-pairs cohort study at an academic tertiary children's hospital. FEES and Videofluoroscopic Swallowing Study (VFSS) trials performed within the same infant <5 days apart were paired by matching bolus consistency and bottle flow rate. Positive aspiration was defined by the "or rule" in which aspiration is positive when either FEES or VFSS within a matched pair is positive. RESULTS: Eighty-seven FEES-VFSS matched pairs from 29 patients (16 males; mean [SD] age, 2.9 [2.8] months) were included. The rate of positive aspiration, as defined by the "or rule", was 59% (51/87). In FEES, post-swallow pyriform sinus residue was present in 16% (14/87) and anterior commissure residue 27% (31/87). Risk of positive aspiration was increased by pyriform sinus residue (odds ratio [OR] 5.4, 95% confidence interval [CI] 1.9-19.3, p < 0.01) and anterior commissure residue in FEES (OR 2.5, 95% CI 1.1-6.1, p = 0.03). In the neonate subgroup, <1 month of age, multivariate-adjusted analysis showed that anterior commissure residue had better diagnostic accuracy for aspiration than in older infants (overall 70% vs. 42%, p < 0.01; sensitivity 60% vs. 10%, p < 0.01), whereas pyriform sinus residue had worse accuracy (overall 41% vs. 70%, p = 0.02; sensitivity 13% vs. 43%, p = 0.02). CONCLUSION: This study demonstrates that pyriform sinus and anterior commissure residue during infant FEES were associated with fivefold and twofold increased risk of aspiration, respectively. LEVEL OF EVIDENCE: 3: Using a retrospective matched-pairs cohort, this study assesses the diagnostic accuracy of post-swallow residue in FEES for predicting aspiration. Laryngoscope, 134:1431-1436, 2024.


Subject(s)
Deglutition Disorders , Deglutition , Male , Infant , Infant, Newborn , Child , Humans , Aged , Child, Preschool , Deglutition Disorders/diagnostic imaging , Deglutition Disorders/etiology , Retrospective Studies , Cohort Studies , Endoscopy/adverse effects , Respiratory Aspiration/diagnostic imaging , Respiratory Aspiration/etiology
14.
Laryngoscope ; 134(2): 614-621, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37338090

ABSTRACT

OBJECTIVE: Chronic sialadenitis is associated with decreased quality of life and recurrent infections. While sialendoscopy with stenting is effective in relieving symptoms of sialadenitis, currently available stents are rigid and poorly tolerated by patients, leading to early removal and potential for adverse scarring. This study examines whether sutures can be used as a stenting material to improve patient comfort and reduce recurrence risk. METHODS: This is a retrospective cohort study of a consecutive series of adult patients with chronic sialadenitis undergoing sialendoscopy with or without suture stenting. Data were collected between 2014 and 2018 with a 3-year follow-up period ending in 2021. The primary outcome measure was recurrence of sialadenitis within 3 years of surgery. Secondary outcomes were stent dislodgement and patient-reported discomfort. RESULTS: We included 63 patients with parotid sialadenitis of whom 28 underwent suture stenting and 35 did not receive stenting after sialendoscopy. Stents were well tolerated, with a mean duration of 34.5 days, and only 2 of 28 stents (7.1%) accidentally dislodged within the first week. Suture stenting significantly reduced symptom recurrence after sialendoscopy (OR = 0.09, 95% CI 0.02-0.45, p = 0.003; 3-year sialadenitis recurrence rate: 7.1% vs. 45.7%, p = 0.005). Cox multivariate regression for clinicodemographic variables showed an HR of 0.04 (95% CI 0.01-0.19, p < 0.001) for the risk of symptom recurrence. CONCLUSIONS AND RELEVANCE: Suture stenting after sialendoscopy is low cost, available across all institutions, well-tolerated by patients, and highly efficacious in reducing risk of recurrent sialadenitis after sialendoscopy. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:614-621, 2024.


Subject(s)
Parotitis , Sialadenitis , Adult , Humans , Quality of Life , Retrospective Studies , Endoscopy/adverse effects , Endoscopy/methods , Treatment Outcome , Sialadenitis/surgery , Sialadenitis/diagnosis , Chronic Disease , Sutures
15.
Article in English | MEDLINE | ID: mdl-38095806

ABSTRACT

Women with hypopituitarism have lower fertility rates and worse pregnancy outcomes than women with normal pituitary function. These disparities exist despite the use of assisted reproductive technologies and hormone replacement. In women with hypogonadotropic hypogonadism, administration of exogenous gonadotropins can be used to successfully induce ovulation. Growth hormone replacement in the setting of growth hormone deficiency has been suggested to potentiate reproductive function, but its routine use in hypopituitary women remains unclear and warrants further study. In this review, we will discuss the clinical approach to fertility in a woman with hypopituitarism.

17.
J Dent Sci ; 18(4): 1960-1962, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37799863
19.
Adv Med Educ Pract ; 14: 963-972, 2023.
Article in English | MEDLINE | ID: mdl-37701423

ABSTRACT

Background: The COVID-19 pandemic and a movement away from traditional lecture-based learning have increased the use of online flipped classroom (FC) and active learning models in medical education. The Community of Inquiry (CoI) framework for online learning may be used to evaluate the effectiveness and strengths of the online FC model compared with other learning formats. Methods: An observational survey study was conducted to measure medical student and facilitator perceptions of an online FC endocrinology tutorial compared with online lecture experiences. For the tutorial, students were instructed to watch short, pre-recorded lecture videos on thyroid pathophysiology prior to class. During class, small groups of students were paired with a faculty facilitator in online Zoom rooms for case discussion. Students were surveyed using the CoI framework to assess elements of cognitive, social, and teaching presence between the two online learning modalities. Facilitators were also surveyed. Survey questions were rated on a 5-point Likert scale. Results: Fifty-three out of 92 students (58% response rate) and seven out of eight facilitators (88% response rate) completed surveys. In general, students felt that online FC learning improved cognitive, teaching, and social presence compared with online lecture. Areas of cognitive presence (mean score 3.9 ± 1.0 SD), such as stimulating curiosity and applying concepts, were highly rated. Certain elements of social presence (3.6 ± 0.9) and teaching presence (3.7 ± 0.9), such as expression of emotion and communication of expectations, garnered lower ratings. All surveyed facilitators felt that online FC was more effective and enjoyable to teach than online lectures but did not feel it was superior to in-person instruction. Conclusion: Medical students and facilitators viewed an online FC tutorial in endocrinology positively. Most, but not all, areas of the CoI framework were enhanced with the online FC tutorial compared with online lecture-based learning.

20.
Angew Chem Int Ed Engl ; 62(44): e202308822, 2023 Oct 26.
Article in English | MEDLINE | ID: mdl-37466460

ABSTRACT

Combustion is often difficult to spatially direct or tune associated kinetics-hence a run-away reaction. Coupling pyrolytic chemical transformation to mass transport and reaction rates (Damköhler number), however, we spatially directed ignition with concomitant switch from combustion to pyrolysis (low oxidant). A 'surface-then-core' order in ignition, with concomitant change in burning rate,is therefore established. Herein, alkysilanes grafted onto cellulose fibers are pyrolyzed into non-flammable SiO2 terminating surface ignition propagation, hence stalling flame propagating. Sustaining high temperatures, however, triggers ignition in the bulk of the fibers but under restricted gas flow (oxidant and/or waste) hence significantly low rate of ignition propagation and pyrolysis compared to open flame (Liñán's equation). This leads to inside-out thermal degradation and, with felicitous choice of conditions, formation of graphitic tubes. Given the temperature dependence, imbibing fibers with an exothermically oxidizing synthon (MnCl2 ) or a heat sink (KCl) abets or inhibits pyrolysis leading to tuneable wall thickness. We apply this approach to create magnetic, paramagnetic, or oxide containing carbon fibers. Given the surface sensitivity, we illustrate fabrication of nm- and µm-diameter tubes from appropriately sized fibers.

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