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1.
Appl Opt ; 63(12): 3359-3365, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856488

RESUMO

Single-line-defect (W1) photonic crystal waveguides hold significant promise for various applications in integrated photonics due to their ability to induce slow light across wide photonic band ranges. Ensuring the manufacturing reliability of these devices is paramount for their practical implementation, as they tend to be highly sensitive to fabrication deviations. In this study, we investigated the manufacturing reliability of photonic crystal waveguides fabricated at the Albany Nanotech Complex foundry by comparing the consistency of band-edge locations and group indices across 14 chips. We also provide FIB images of the fabricated photonic crystals allowing an analysis of the sidewall quality of the holes.

2.
Am J Respir Crit Care Med ; 208(8): 837-845, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37582154

RESUMO

Rationale: Strict adherence to procedural protocols and diagnostic definitions is critical to understand the efficacy of new technologies. Electromagnetic navigational bronchoscopy (ENB) for lung nodule biopsy has been used for decades without a solid understanding of its efficacy, but offers the opportunity for simultaneous tissue acquisition via electromagnetic navigational transthoracic biopsy (EMN-TTNA) and staging via endobronchial ultrasound (EBUS). Objective: To evaluate the diagnostic yield of EBUS, ENB, and EMN-TTNA during a single procedure using a strict a priori definition of diagnostic yield with central pathology adjudication. Methods: A prospective, single-arm trial was conducted at eight centers enrolling participants with pulmonary nodules (<3 cm; without computed tomography [CT]- and/or positron emission tomography-positive mediastinal lymph nodes) who underwent a staged procedure with same-day CT, EBUS, ENB, and EMN-TTNA. The procedure was staged such that, when a diagnosis had been achieved via rapid on-site pathologic evaluation, the procedure was ended and subsequent biopsy modalities were not attempted. A study finding was diagnostic if an independent pathology core laboratory confirmed malignancy or a definitive benign finding. The primary endpoint was the diagnostic yield of the combination of CT, EBUS, ENB, and EMN-TTNA. Measurements and Main Results: A total of 160 participants at 8 centers with a mean nodule size of 18 ± 6 mm were enrolled. The diagnostic yield of the combined procedure was 59% (94 of 160; 95% confidence interval [CI], 51-66%). Nodule regression was found on same-day CT in 2.5% of cases (4 of 160; 95% CI, 0.69-6.3%), and EBUS confirmed malignancy in 7.1% of cases (11 of 156; 95% CI, 3.6-12%). The yield of ENB alone was 49% (74 of 150; 95% CI, 41-58%), that of EMN-TTNA alone was 27% (8 of 30; 95% CI, 12-46%), and that of ENB plus EMN-TTNA was 53% (79 of 150; 95% CI, 44-61%). Complications included a pneumothorax rate of 10% and a 2% bleeding rate. When EMN-TTNA was performed, the pneumothorax rate was 30%. Conclusions: The diagnostic yield for ENB is 49%, which increases to 59% with the addition of same-day CT, EBUS, and EMN-TTNA, lower than in prior reports in the literature. The high complication rate and low diagnostic yield of EMN-TTNA does not support its routine use. Clinical trial registered with www.clinicaltrials.gov (NCT03338049).

3.
Ann Hepatol ; 29(4): 101510, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38714224

RESUMO

INTRODUCTION AND OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide and can progress to non-alcoholic steatohepatitis (NASH) and, ultimately, cirrhosis. Clostridioides difficile is the most common nosocomial cause of diarrhea and is associated with worse clinical outcomes in other liver diseases, including cirrhosis, but has not been extensively evaluated in concomitant NAFLD/NASH. MATERIALS AND METHODS: We conducted a retrospective cohort study using the National Inpatient Sample database from 2015 to 2017. Patients with a diagnosis of CDI, NAFLD, and NASH were identified using International Classification of Diseases (Tenth Revision) codes. The outcomes of our study include length of stay, hospitalization cost, mortality, and predictors of mortality. RESULTS: The CDI and NASH cohort had a higher degree of comorbidity burden and prevalence of peptic ulcer disease, congestive heart failure, diabetes mellitus, and cirrhosis. Patients with NASH and CDI had a significantly higher mortality rate compared to the CDI only cohort (mortality, 7.11 % vs. 6.36 %; P = 0.042). Patients with CDI and NASH were at increased risk for liver-related complications, acute kidney injury, and septic shock (P < 0.001) compared to patients with CDI only. Older age, intestinal complications, pneumonia, sepsis and septic shock, and liver failure conferred an increased risk of mortality among the CDI and NASH cohort. CONCLUSIONS: Patients with NASH had a higher rate of liver-related complications, progression to septic shock, and mortality rate following CDI infection compared to the CDI only cohort.

4.
Perception ; 53(1): 17-30, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37859336

RESUMO

Everyday experiences suggest that a container, such as a box of cereal, can convey pertinent information about the nature and quantity of its content. This study investigated how well people can judge large quantities of objects in a container through haptic perception. Stimuli consisted of plastic drinking straws cut to "small" (1.5 cm) or "big" (4.5 cm) pieces contained in plastic food containers. Participants performed both a magnitude estimation of the number of objects and a direct estimation of the proportion of the container perceived to be filled with objects. Overall, participants demonstrated considerable accuracy for both tasks and irrespective of the size of the content. Post-experiment interviews revealed three potential strategies. Participants either focused on the container's contents, the excess space in the container, or the perceived weight of the container (content).


Assuntos
Percepção do Tato , Tato , Humanos
5.
J Am Chem Soc ; 145(46): 25401-25410, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37948677

RESUMO

Nanosized particles of liquid metals are emerging materials that hold promise for applications spanning from microelectronics to catalysis. Yet, knowledge of their chemical reactivity is largely unknown. Here, we study the reactivity of liquid Ga and Cu nanoparticles under the application of a cathodic voltage. We discover that the applied voltage and the spatial proximity of these two particle precursors dictate the reaction outcome. In particular, we find that a gradual voltage ramp is crucial to reduce the native oxide skin of gallium and enable reactive wetting between the Ga and Cu nanoparticles; instead, a voltage step causes dewetting between the two. We determine that the use of liquid Ga/Cu nanodimer precursors, which consist of an oxide-covered Ga domain interfaced with a metallic Cu domain, provides a more uniform mixing and results in more homogeneous reaction products compared to a physical mixture of Ga and Cu NPs. Having learned this, we obtain CuGa2 alloys or solid@liquid CuGa2@Ga core@shell nanoparticles by tuning the stoichiometry of Ga and Cu in the nanodimer precursors. These products reveal an interesting complementarity of thermal and voltage-driven syntheses to expand the compositional range of bimetallic NPs. Finally, we extend the voltage-driven synthesis to the combination of Ga with other elements (Ag, Sn, Co, and W). By rationalizing the impact of the native skin reduction rate, the wetting properties, and the chemical reactivity between Ga and other metals on the results of such voltage-driven chemical manipulation, we define the criteria to predict the outcome of this reaction and set the ground for future studies targeting various applications for multielement nanomaterials based on liquid Ga.

6.
J Am Chem Soc ; 145(9): 5370-5383, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36847799

RESUMO

Copper nanocatalysts are among the most promising candidates to drive the electrochemical CO2 reduction reaction (CO2RR). However, the stability of such catalysts during operation is sub-optimal, and improving this aspect of catalyst behavior remains a challenge. Here, we synthesize well-defined and tunable CuGa nanoparticles (NPs) and demonstrate that alloying Cu with Ga considerably improves the stability of the nanocatalysts. In particular, we discover that CuGa NPs containing 17 at. % Ga preserve most of their CO2RR activity for at least 20 h while Cu NPs of the same size reconstruct and lose their CO2RR activity within 2 h. Various characterization techniques, including X-ray photoelectron spectroscopy and operando X-ray absorption spectroscopy, suggest that the addition of Ga suppresses Cu oxidation at open-circuit potential (ocp) and induces significant electronic interactions between Ga and Cu. Thus, we explain the observed stabilization of the Cu by Ga as a result of the higher oxophilicity and lower electronegativity of Ga, which reduce the propensity of Cu to oxidize at ocp and enhance the bond strength in the alloyed nanocatalysts. In addition to addressing one of the major challenges in CO2RR, this study proposes a strategy to generate NPs that are stable under a reducing reaction environment.

7.
Phys Rev Lett ; 131(11): 111004, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774289

RESUMO

Axions can be copiously produced in localized regions of neutron star magnetospheres where the ambient plasma is unable to efficiently screen the induced electric field. As these axions stream away from the neutron star they can resonantly transition into photons, generating a large broadband contribution to the neutron star's intrinsic radio flux. In this Letter, we develop a comprehensive end-to-end framework to model this process from the initial production of axions to the final detection of radio photons, and derive constraints on the axion-photon coupling, g_{aγγ}, using observations of 27 nearby pulsars. We study the modeling uncertainty in the sourced axion spectrum by comparing predictions from 2.5 dimensional particle-in-cell simulations with those derived using a semianalytic model; these results show remarkable agreement, leading to constraints on the axion-photon coupling that typically differ by a factor of no more than ∼2. The limits presented here are the strongest to date for axion masses 10^{-8} eV≲m_{a}≲10^{-5} eV, and crucially do not rely on the assumption that axions are dark matter.

8.
Respiration ; 102(5): 370-376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36996776

RESUMO

BACKGROUND: Peripheral bronchoscopy is often performed to biopsy peripheral pulmonary lesions. Despite technological advancements to improve reach and access to the lung periphery, the diagnostic yield of peripheral bronchoscopy has been inconsistent, and challenging, particularly for lesions that are adjacent to peripheral bronchi. Current biopsy instruments are reliant on the catheter or scope to align properly with targeted lesions. OBJECTIVES: This study evaluates the feasibility of using a steerable biopsy needle to gain access to peripheral tumor targets in a cadaveric model. METHODS: Simulated tumor targets 10-30 mm in axial diameter were placed into human cadavers. Bronchoscopy was performed using a 4.2 mm OD flexible bronchoscope, CT-anatomic correlation, and multi-planar fluoroscopy for lesion localization. Once at the targeted location, a steerable needle was deployed and the needle position was determined to be in the central zone, peripheral zone, or outside of the lesion by cone beam CT imaging. If the needle position was within the lesion, a fiducial marker was deployed to mark the needle position, and the needle was articulated and/or rotated in an attempt to place another fiducial marker into a different location within the same lesion. If the needle was outside of the lesion, the bronchoscopist was provided with two additional attempts to gain access to the lesion. RESULTS: Fifteen tumor targets were placed with a mean lesion size of 20.4 mm. The majority of lesions were located in the upper lobes. One fiducial marker was placed in 93.3% of lesions and a second fiducial marker was successfully placed in 80% of lesions. A fiducial marker was placed within the central zone in 60% of lesions. CONCLUSION: The steerable needle was successfully placed within 93% of targeted lesions 10-30 mm in diameter in a cadaveric model, with the ability steer the instrument into another portion of the lesion in 80% of cases. The ability to steer and control needle positioning toward and within peripheral lesions may complement existing catheter and scope technology during peripheral diagnostic procedures.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Estudos de Viabilidade , Pulmão/patologia , Biópsia , Broncoscopia/métodos
9.
Biophys J ; 121(9): 1619-1631, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35378080

RESUMO

Mechanistic insights into human respiratory tract (RT) infections from SARS-CoV-2 can inform public awareness as well as guide medical prevention and treatment for COVID-19 disease. Yet the complexity of the RT and the inability to access diverse regions pose fundamental roadblocks to evaluation of potential mechanisms for the onset and progression of infection (and transmission). We present a model that incorporates detailed RT anatomy and physiology, including airway geometry, physical dimensions, thicknesses of airway surface liquids (ASLs), and mucus layer transport by cilia. The model further incorporates SARS-CoV-2 diffusivity in ASLs and best-known data for epithelial cell infection probabilities, and, once infected, duration of eclipse and replication phases, and replication rate of infectious virions. We apply this baseline model in the absence of immune protection to explore immediate, short-term outcomes from novel SARS-CoV-2 depositions onto the air-ASL interface. For each RT location, we compute probability to clear versus infect; per infected cell, we compute dynamics of viral load and cell infection. Results reveal that nasal infections are highly likely within 1-2 days from minimal exposure, and alveolar pneumonia occurs only if infectious virions are deposited directly into alveolar ducts and sacs, not via retrograde propagation to the deep lung. Furthermore, to infect just 1% of the 140 m2 of alveolar surface area within 1 week, either 103 boluses each with 106 infectious virions or 106 aerosols with one infectious virion, all physically separated, must be directly deposited. These results strongly suggest that COVID-19 disease occurs in stages: a nasal/upper RT infection, followed by self-transmission of infection to the deep lung. Two mechanisms of self-transmission are persistent aspiration of infected nasal boluses that drain to the deep lung and repeated rupture of nasal aerosols from infected mucosal membranes by speaking, singing, or cheering that are partially inhaled, exhaled, and re-inhaled, to the deep lung.


Assuntos
COVID-19 , Aerossóis , Humanos , Pulmão , SARS-CoV-2 , Carga Viral
10.
BMC Pulm Med ; 22(1): 26, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991528

RESUMO

BACKGROUND: Incidental and screening-identified lung nodules are common, and a bronchoscopic evaluation is frequently nondiagnostic. The Percepta Genomic Sequencing Classifier (GSC) is a genomic classifier developed in current and former smokers which can be used for further risk stratification in these patients. Percepta GSC has the capability of up-classifying patients with a pre-bronchoscopy risk that is high (> 60%) to "very high risk" with a positive predictive value of 91.5%. This prospective, randomized decision impact survey was designed to test the hypothesis that an up-classification of risk of malignancy from high to very high will increase the rate of referral for surgical or ablative therapy without additional intervening procedures while increasing physician confidence. METHODS: Data were collected from 37 cases from the Percepta GSC validation cohort in which the pre-bronchoscopy risk of malignancy was high (> 60%), the bronchoscopy was nondiagnostic, and the patient was up-classified to very high risk by Percepta GSC. The cases were randomly presented to U.S pulmonologists in three formats: a pre-post cohort where each case is presented initially without and then with a GSG result, and two independent cohorts where each case is presented either with or without with a GSC result. Physicians were surveyed with respect to subsequent management steps and confidence in that decision. RESULTS: One hundred and one survey takers provided a total of 1341 evaluations of the 37 patient cases across the three different cohorts. The rate of recommendation for surgical resection was significantly higher in the independent cohort with a GSC result compared to the independent cohort without a GSC result (45% vs. 17%, p < 0.001) In the pre-post cross-over cohort, the rate increased from 17 to 56% (p < 0.001) following the review of the GSC result. A GSC up-classification from high to very high risk of malignancy increased Pulmonologists' confidence in decision-making following a nondiagnostic bronchoscopy. CONCLUSIONS: Use of the Percepta GSC classifier will allow more patients with early lung cancer to proceed more rapidly to potentially curative therapy while decreasing unnecessary intervening diagnostic procedures following a nondiagnostic bronchoscopy.


Assuntos
Tomada de Decisão Clínica/métodos , Genômica , Neoplasias Pulmonares/psicologia , Pneumologistas/psicologia , Idoso , Idoso de 80 Anos ou mais , Broncoscopia , Estudos de Coortes , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fumar , Inquéritos e Questionários , Estados Unidos
11.
Graefes Arch Clin Exp Ophthalmol ; 259(8): 2287-2294, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33893867

RESUMO

PURPOSE: To assess the reliability of a tear film (TF) viscosity video grading system. METHODS: Thirty-four dynamic TF viscosity videos were obtained by a clinically available TF analyzer and objectively sorted according to the movement speed of three arbitrary reflective light particles. A 4-grade system was constructed on a specially designed window for simultaneous comparison with the three standard videos. Two masked graders were invited to grade these videos under a randomized procedure. Observer reliabilities were determined by Spearman's correlation analysis and Bland-Altman agreement analysis. RESULTS: For this four-grade system, the intra-observer correlation was very strong in the two graders (ρ = 0.96 and 0.82; both P < 0.0001). However, the inter-observer correlation showed moderate strength in normal playback speed (ρ = 0.53, P = 0.002 and ρ = 0.52, P = 0.003 for 1st and 2nd gradings, respectively). In slower playback videos, the inter-observer correlation of the two graders was higher (ρ = 0.70 and P < 0.0001) when reduced to 0.8-times playback speed. Moreover, the 0.8-times mode was also significantly better than normal playback mode (P = 0.0204) in terms of inter-observer agreement. CONCLUSIONS: The dynamic 4-grade system has an excellent intra-observer reliability and a good inter-observer reliability under 0.8-times playback speed. The grading system established in this study provides a promising solution for rapidly determining the level of TF viscosity.


Assuntos
Lágrimas , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Viscosidade
12.
J Cardiothorac Vasc Anesth ; 35(2): 508-513, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32029371

RESUMO

OBJECTIVE: The aim of this study was to find out whether the preoperative continuation of angiotensin-converting enzyme inhibitor (ACE-I) or angiotensin II receptor blocker (ARB) treatment is associated with intraoperative hypotension immediately after induction of general anesthesia in elective noncardiac surgeries. DESIGN: Retrospective cohort study. SETTING: Single institutional university hospital. PARTICIPANTS: Four hundred patients who underwent elective noncardiac surgery under general anesthesia, with ACE-I or ARB on their list of preoperative home medications, were included. INTERVENTION: Preoperative ACE-I and ARB use was evaluated, and patients were divided into an ACE-I/ARB group versus non-ACE-I/ARB group. MEASUREMENTS: The primary outcome measure was intraoperative hypotension after induction of general anesthesia. The secondary outcome measure was preoperative medication use, medications taken the morning of surgery, induction medication and dosage, and vasopressor medication use during induction. RESULTS: Three hundred forty-nine patients were included for final analysis. The mean admission American Society of Anesthesiologists status was 2.7 ± 0.5, age 65 ± 11 years, and body mass index 31 ± 6.9 kg/m2. There were no statistically significant changes between the no ACE-I/ARB group and the ACE-I/ARB group in systolic blood pressure (p = 0.853), diastolic blood pressure (p = 0.357), and heart rate (p = 0.220) change over the 15 minutes. There was no statistical difference in induction medication dose (propofol, fentanyl, and rocuronium) and pressor use (p = 0.137) for hypotension between the 2 groups. Statistically significant hypotension (p < 0.001) occurred in both groups equally over 15 minutes. CONCLUSION: Continuation of ACE-I/ARB on the day of surgery was not associated with increased risk of intraoperative hypotension upon induction and within 15 minutes of general anesthesia in elective noncardiac surgeries.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Hipotensão , Idoso , Anestesia Geral/efeitos adversos , Antagonistas de Receptores de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Humanos , Hipotensão/induzido quimicamente , Hipotensão/diagnóstico , Hipotensão/epidemiologia , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
J Formos Med Assoc ; 120(12): 2153-2159, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33422400

RESUMO

BACKGROUND/PURPOSE: A modified novel analytical method for evaluating photographic retinal nerve fiber layer defect (RNFLD) was developed for the purpose of estimating the severity of early glaucomatous eyes. This new method was then compared with the original method, as described below, in relation to the visual field defect severity. METHODS: The clinical records of 47 glaucomatous eyes with qualified photographs were obtained from a prior retrospective study. The reference point of the angle was set at the center of the optic disc center (COD group) and the central vessel trunk (COV group). Angle α was the angular width between the fovea and the proximity of RNFLD, while angle ß (+c) was the sum of the angular width(s) of localized RNFLD. The correlation between the visual field parameters and the angles of RNFLD in the above two groups were analyzed. RESULTS: There were significant differences in angle α (p = 0.001) and angle ß (+c) (p = 0.016) between the two groups. Angle ß (+c) showed significant correlation with MD (p = 0.012), PSD (p = 0.035), VFI (p = 0.042) and MD (p = 0.016), PSD (p = 0.035), VFI (p = 0.031) in the COD and COV group, respectively. No correlation was found between angle α and the presence of central scotoma in both groups. CONCLUSION: Our novel method was more convenient in a clinical setting and noninferior to the original method.


Assuntos
Fibras Nervosas , Campos Visuais , Humanos , Pressão Intraocular , Estudos Retrospectivos , Testes de Campo Visual
14.
Nano Lett ; 20(5): 3331-3337, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32202803

RESUMO

We report on the thermal conductivities of two-dimensional metal halide perovskite films measured by time domain thermoreflectance. Depending on the molecular substructure of ammonium cations and owing to the weaker interactions in the layered structures, the thermal conductivities of our two-dimensional hybrid perovskites range from 0.10 to 0.19 W m-1 K-1, which is drastically lower than that of their three-dimensional counterparts. We use molecular dynamics simulations to show that the organic component induces a reduction of the stiffness and sound velocities along with giving rise to vibrational modes in the 5-15 THz range that are absent in the three-dimensional counterparts. By systematically studying eight different two-dimensional hybrid perovskites, we show that the thermal conductivities of our hybrid films do not depend on the thicknesses of the organic layers and instead are highly dependent on the relative orientation of the organic chains sandwiched between the inorganic constituents.

15.
Int J Mol Sci ; 22(1)2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33401599

RESUMO

Most studies about dry eye disease (DED) chose unilateral eye for investigation and drew conclusions based on monocular results, whereas most studies involving tear proteomics were based on the results of pooling tears from a group of DED patients. Patients with DED were consecutively enrolled for binocular clinical tests, tear biochemical markers of DED, and tear proteome. We found that bilateral eyes of DED patients may have similar but different ocular surface performance and tear proteome. Most ocular surface homeostatic markers and tear biomarkers were not significantly different in the bilateral eyes of DED subjects, and most clinical parameters and tear biomarkers were correlated significantly between bilateral eyes. However, discrepant binocular presentation in the markers of ocular surface homeostasis and the associations with tear proteins suggested that one eye's performance cannot represent that of the other eye or both eyes. Therefore, in studies for elucidating tear film homeostasis of DED, we may lose some important messages hidden in the fellow eye if we collected clinical and proteomic data only from a unilateral eye. For mechanistic studies, it is recommended that researchers collect tear samples from the eye with more severe DED under sensitive criteria for identifying the more severe eye and evaluating the tear biochemical and proteomic markers with binocular concordance drawn in prior binocular studies.


Assuntos
Biomarcadores/metabolismo , Síndromes do Olho Seco/patologia , Proteínas do Olho/metabolismo , Olho/metabolismo , Inflamação/patologia , Proteoma/análise , Lágrimas/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Síndromes do Olho Seco/imunologia , Síndromes do Olho Seco/metabolismo , Feminino , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Pessoa de Meia-Idade , Estudos Prospectivos , Lágrimas/química , Adulto Jovem
16.
J Chem Phys ; 152(1): 014703, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31914767

RESUMO

The extended charge carrier lifetime in metal halide perovskites is responsible for their excellent optoelectronic properties. Recent studies indicate that the superb device performance in these materials is intimately related to the organic cation dynamics. Here, we focus on the investigation of the two-dimensional hybrid perovskite, (C8H17NH3)2PbI4 (henceforth, OA+ = C8H17NH3 +). Using elastic and quasielastic neutron scattering techniques and group theoretical analysis, we studied the structural phase transitions and rotational modes of the C8H17NH3 + cation in (OA)2PbI4. Our results show that, in the high-temperature orthorhombic (T > 310 K) phase, the OA+ cation exhibits a combination of a twofold rotation of the NH3-CH2 head group about the crystal c-axis with a characteristic relaxation time of ∼6.2 ps, threefold rotations (C3) of NH3 and CH3 terminal groups, and slow librations of the other atoms. Contrastingly, only the C3 rotation is present in the intermediate-temperature orthorhombic (238 K < T < 310 K) and low-temperature monoclinic (T < 238 K) phases.

17.
Respiration ; 99(1): 56-61, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31805570

RESUMO

BACKGROUND: Bronchoscopy for the diagnosis of peripheral pulmonary lesions continues to present clinical challenges, despite increasing experience using newer guided techniques. Robotic bronchoscopic platforms have been developed to potentially improve diagnostic yields. Previous studies in cadaver models have demonstrated increased reach into the lung periphery using robotic systems compared to similarly sized conventional bronchoscopes, although the clinical impact of additional reach is unclear. OBJECTIVES: This study was performed to evaluate the performance of a robotic bronchoscopic system's ability to reach and access artificial tumor targets simulating peripheral nodules in human cadaveric lungs. METHODS: Artificial tumor targets sized 10-30 mm in axial diameter were implanted into 8 human cadavers. CT scans were performed prior to procedures and all cadavers were intubated and mechanically ventilated. Electromagnetic navigation, radial probe endobronchial ultrasound, and fluoroscopy were used for all procedures. Robotic-assisted bronchoscopy was performed on each cadaver by an individual bronchoscopist to localize and biopsy peripheral lesions. RESULTS: Sixty-seven nodules were evaluated in 8 cadavers. The mean nodule size was 20.4 mm. The overall diagnostic yield was 65/67 (97%) and there was no statistical difference in diagnostic yield for lesions <20 mm compared with lesions measuring 21-30 mm, the presence of a concentric or eccentric radial ultrasound image, or relative distance from the pleura. CONCLUSIONS: The robotic bronchoscopic system was successful at biopsying 97% of peripheral pulmonary lesions 10-30 mm in size in human cadavers. These findings support further exploration of this technology in prospective clinical trials in live human subjects.


Assuntos
Broncoscopia/métodos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Neoplasias Pulmonares/patologia , Procedimentos Cirúrgicos Robóticos/métodos , Nódulo Pulmonar Solitário/patologia , Biópsia , Cadáver , Endossonografia , Feminino , Humanos , Masculino
18.
BMC Ophthalmol ; 20(1): 141, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32272929

RESUMO

BACKGROUND: In order to detect glaucomatous optic nerve damages early on and evaluate the severity of glaucoma, a previously developed analytic method based on photographic retinal nerve fiber layer (RNFL) angle defect was proposed. However, the correlation between these defective angles and the severity of visual field defect has not been verified. This study aimed to confirm the correlation described above. METHODS: We reviewed a total of 227 glaucomatous eyes (38 enrolled, 189 excluded) during an interval of 5 years. The angles of all eyes were measured on RNFL photograph, of which angle α is the angular width between the macula center and the proximity of RNFL defect, and angle ß (+c) is the sum of angular width(s) of localized RNFL defect. The severity of visual field defect was determined by mean deviation (MD), pattern standard deviation (PSD), and visual field index (VFI). Correlation analysis was performed on angle α and angle ß (+c) with the presence of central scotoma and visual field defect parameters, respectively. RESULTS: Angle ß (+c) showed significant correlation with MD (P = 0.007), PSD (P = 0.02), VFI (P = 0.03), and average RNFL thickness (P = 0.03). No correlation was found between angle α and the presence of central scotoma. CONCLUSIONS: In conclusion, measuring the angular width of localized RNFL defect is a viable method for determining the severity of visual field defect.


Assuntos
Glaucoma de Ângulo Aberto/diagnóstico , Fibras Nervosas/patologia , Doenças do Nervo Óptico/diagnóstico , Células Ganglionares da Retina/patologia , Escotoma/fisiopatologia , Campos Visuais/fisiologia , Idoso , Estudos Transversais , Feminino , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Doenças do Nervo Óptico/fisiopatologia , Fotografação , Tomografia de Coerência Óptica , Tonometria Ocular , Testes de Campo Visual
19.
Int J Mol Sci ; 21(21)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167500

RESUMO

A sound ocular surface microbiota has been recognized as a part of ocular surface health following a growing body of evidence from next-generation sequencing technique and metagenomic analysis. However, even from the perspective of contemporary precision medicine, it is difficult to directly apply these new technologies to clinical practice. Therefore, we proposed a model based on dot hybridization assay (DHA) to bridge conventional culture with a metagenomic approach in investigating and monitoring ocular surface microbiota. Endophthalmitis, mostly caused by bacterial infection, is the most severe complication of many intraocular surgeries, such as cataract surgery. Hazardous microorganisms hiding and proliferating in the ocular surface microbiota not only increase the risk of endophthalmitis but also jeopardize the effectiveness of the preoperative aseptic procedure and postoperative topical antibiotics. The DHA model enables the simultaneous assessment of bacterial bioburden, detection of target pathogens and microorganisms, and surveillance of methicillin/oxacillin resistance gene mecA in the ocular surface microbiota. This assay revealed heavier bacterial bioburden in men, compatible with a higher risk of endophthalmitis in male patients who underwent cataract surgery. No occurrence of endophthalmitis for these patients was compatible with non-hazardous microorganisms identified by specific dots for target pathogens. Moreover, the mecA dot detected oxacillin-resistant strains, of which culture failed to isolate. Therefore, the DHA model could provide an alternative genomic approach to investigate and monitor ocular surface microorganisms in clinical practice nowadays.


Assuntos
Pálpebras/microbiologia , Microbiota/genética , Hibridização de Ácido Nucleico/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Bactérias/isolamento & purificação , Extração de Catarata/efeitos adversos , Endoftalmite/etiologia , Olho/microbiologia , Infecções Oculares Bacterianas , Feminino , Genômica/métodos , Humanos , Masculino , Pessoa de Meia-Idade
20.
J Infect Dis ; 220(220 Suppl 4): S190-S197, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31671437

RESUMO

In 2016, Mali reported a bacterial meningitis outbreak consisting of 39 suspected cases between epidemiologic weeks 9 and 17 with 15% case fatality ratio in the health district of Ouéléssebougou, 80 kilometers from the capital Bamako. Cerebrospinal fluid specimens from 29 cases were tested by culture and real-time polymerase chain reaction; 22 (76%) were positive for bacterial meningitis pathogens, 16 (73%) of which were Neisseria meningitidis (Nm). Of the Nm-positive specimens, 14 (88%) were N meningitidis serogroup C (NmC), 1 was NmW, and 1 was nongroupable. Eight NmC isolates recovered by culture from the outbreak were characterized using whole genome sequencing. Genomics analysis revealed that all 8 isolates belonged to a new sequence type (ST) 12446 of clonal complex 10217 that formed a distinct clade genetically similar to ST-10217, a NmC strain that recently caused large epidemics of meningitis in Niger and Nigeria. The emergence of a new ST of NmC associated with an outbreak in the African meningitis belt further highlights the need for continued molecular surveillance in the region.


Assuntos
Surtos de Doenças , Genótipo , Meningite Meningocócica/epidemiologia , Meningite Meningocócica/microbiologia , Neisseria meningitidis Sorogrupo C/genética , Adolescente , Adulto , Criança , Feminino , Variação Genética , Genoma Bacteriano , Geografia Médica , História do Século XXI , Humanos , Masculino , Mali/epidemiologia , Meningite Meningocócica/diagnóstico , Meningite Meningocócica/história , Neisseria meningitidis Sorogrupo C/classificação , Filogenia , Estações do Ano , Sequenciamento Completo do Genoma , Adulto Jovem
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