Tandem Solar Cells from Solution-Processed CdTe and PbS Quantum Dots Using a ZnTe–ZnO Tunnel Junction

Crisp, Ryan W.,Pach, Gregory F.,Kurley, J. Matthew,France, Ryan M.,Reese, Matthew O.,Nanayakkara, Sanjini U.,MacLeod, Bradley A.,Talapin, Dmitri V.,Beard, Matthew C.,Luther, Joseph M. American Chemical Society 2017 Nano letters Vol.17 No.2

<P>We developed a monolithic CdTe–PbS tandem solar cell architecture in which both the CdTe and PbS absorber layers are solution-processed from nanocrystal inks. Due to their tunable nature, PbS quantum dots (QDs), with a controllable band gap between 0.4 and ∼1.6 eV, are a promising candidate for a bottom absorber layer in tandem photovoltaics. In the detailed balance limit, the ideal configuration of a CdTe (<I>E</I><SUB>g</SUB> = 1.5 eV)–PbS tandem structure assumes infinite thickness of the absorber layers and requires the PbS band gap to be 0.75 eV to theoretically achieve a power conversion efficiency (PCE) of 45%. However, modeling shows that by allowing the thickness of the CdTe layer to vary, a tandem with efficiency over 40% is achievable using bottom cell band gaps ranging from 0.68 and 1.16 eV. In a first step toward developing this technology, we explore CdTe–PbS tandem devices by developing a ZnTe–ZnO tunnel junction, which appropriately combines the two subcells in series. We examine the basic characteristics of the solar cells as a function of layer thickness and bottom-cell band gap and demonstrate open-circuit voltages in excess of 1.1 V with matched short circuit current density of 10 mA/cm<SUP>2</SUP> in prototype devices.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2017/nalefd.2017.17.issue-2/acs.nanolett.6b04423/production/images/medium/nl-2016-04423k_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl6b04423'>ACS Electronic Supporting Info</A></P>

Sentinel-1 Persistent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR) for Long-Term Remote Monitoring of Ground Subsidence: A Case Study of a Port in Busan, South Korea

Ryan Angeles Ramirez,권태혁 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.10

Reclamation has allowed rapid land expansions for economic zones, residential areas, airports, industrial parks, and seaports. Meanwhile, the reclaimed lands often pose a risk of ground subsidence, jeopardizing functions of aboveground infrastructures, buildings, and facilities and threatening human lives. Therefore, it is critical to systematically monitor and manage the reclaimed lands after construction and minimize geohazard risks. This paper presents a case study on long-term remote monitoring of ground subsidence in reclaimed land using satellite synthetic aperture radar (SAR) data and the Persistent Scatterer Interferometric SAR (PS-InSAR) technique. The case study explores the excessive and persistent ground subsidence in Busan New Port, South Korea, which occurred since 2007. We employ large stacks of Sentinel-1 data acquired from the ascending and descending tracks for reliable estimation of ground subsidence and utilize the hyperbolic model, providing an updated prediction tool. A benchmarking and media fact-checking approach consistently supports our PS-InSAR analysis results. The time-series results show that the maximum subsidence rate is approximately -85 mm/yr along the radar line-of-sight (LOS). PS-InSAR can assist in saving expensive and laborious mapping and operational field-survey services and offers essential guidance for the next phase of future construction of Busan New Port.

Lack of recall after sedation for cataract surgery and its effect on validity of measuring patient satisfaction

Ryan M. Chadha,Franklin Dexter,Sorin J. Brull 대한마취통증의학회 2020 Korean Journal of Anesthesiology Vol.73 No.4

Background: We evaluated the validity of assessing patient satisfaction with the sedation regimen among patients being discharged 45 min after receiving midazolam. If most patients do not have recall, then the sedation cannot be considered complete at the time of evaluation. Methods: In this prospective cohort study, 20 patients underwent cataract surgery with nurse-administered midazolam and fentanyl. The 11-item Iowa Satisfaction with Anesthesia Scale was administered ≅ 30 min after sedation in the recovery room. Recalled items were evaluated the next morning. Results: Eleven patients recalled 0 themes, 4 recalled 1, 4 recalled 2, and 1 recalled 3 themes. Thus, 15/20 patients (75%) recalled 0 or 1 of the 11 themes (P = 0.021 versus half the patients). The 95% one-sided lower confidence limit for 0, 1, or 2 themes was 80% of patients (P < 0.001 versus half). Patients who received less midazolam recalled more themes (Kendall’s τb = 0.43, P = 0.039). Conclusions: Evaluating patient satisfaction with sedation shortly after admission to the post-anesthesia care unit is invalid because of a lack of recall; the sedation/amnesia is ongoing. Patient comfort may be assessed, but comfort is not synonymous with satisfaction; ‘satisfaction’ implies presence of recall. Because we studied sedation with low doses of midazolam and fentanyl, the same conclusion reliably would apply to larger doses of anxiolytics administered intraoperatively. The results match previous findings that when patients receive preoperative midazolam prior to meeting the anesthesiologist, even if the patient fully answers questions, they may have negligible recall of having met the anesthesiologist.

Participatory Drama as a Language Teaching Device

Ryan, William E . 한국커뮤니케이션학회 1996 커뮤니케이션학연구 Vol.4 No.1

Outcomes of Bilateral Shoulder Arthroplasties: A Comparison of Bilateral Total Shoulder Arthroplasties and Bilateral Reverse Shoulder Arthroplasties

Ryan Matthew Cox,Tyler James Brolin,Eric Michael Padegimas,Mark David Lazarus,Charles Lonnie Getz,Matthew Lee Ramsey,Gerald Ross Williams,Joseph Albert Abboud 대한정형외과학회 2019 Clinics in Orthopedic Surgery Vol.11 No.3

Background: The purpose of this study was to compare outcomes of patients who underwent bilateral total shoulder arthroplasties (TSAs) for osteoarthritis (OA) versus bilateral reverse shoulder arthroplasties (RSAs) for cuff tear arthropathy (CTA). Methods: Inclusion criteria were patients who underwent bilateral TSAs for OA or bilateral RSAs for CTA with at least 2 years of follow-up. Twenty-six TSA patients (52 shoulders) were matched 2 to 1 with 13 RSA patients (26 shoulders) by sex, age at first surgery, and time between surgeries. Outcomes measured were shoulder range of motion (ROM), complications, and patient-reported scores. Results: Preoperatively, TSA patients had significantly better forward elevation (FE) of both shoulders than RSA patients (dominant side [Dom]: 103° ± 32° vs. 81° ± 31°, p = 0.047; nondominant side [non-Dom]: 111° ± 28° vs. 70° ± 42°, p = 0.005) without significant differences in external (ER) or internal rotation (IR). Postoperatively, TSA patients had significantly better FE (Dom and non-Dom: 156° ± 12°, 156° ± 14° vs. 134° ± 24°, 137° ± 23°; p = 0.006, p = 0.019) and ER (42° ± 11°, 43° ± 10° vs. 24° ± 12°, 25° ± 10°; p < 0.001, p < 0.001) bilaterally and IR of their dominant arm (L1 vs. L4, p = 0.045). TSA patients had significantly better activities of daily living external and internal rotations (ADLEIR) scores (Dom and non-Dom: 35.3 ± 1.0, 35.5 ± 0.9 vs. 32.1 ± 2.4, 32.5 ± 2.2; p = 0.001, p = 0.001), American Shoulder and Elbow Surgeons scores (94.2 ± 8.4, 94.2 ± 8.2 vs. 84.7 ± 10.0, 84.5 ± 8.0; p = 0.015, p = 0.004), and Single Assessment Numerical Evaluation (SANE) scores (93.5 ± 7.6, 93.8 ± 11.8 vs. 80.5 ± 14.2, 82.3 ± 13.1; p = 0.014, p = 0.025), with no significant difference in visual analog scale pain scores (0.4 ± 1.0, 0.3 ± 1.0 vs. 0.7 ± 1.3, 0.8 ± 1.2) bilaterally. Conclusions: Overall, patients with bilateral TSAs and RSAs exhibited improved ROM and patient-reported outcomes. Those with bilateral TSAs had better functional outcomes than those with bilateral RSAs.

Effects of micro-contaminant mixture on the potential toxicity of zebrafish using metabolomics

Ryan De Sotto(라이언 디 소토),Kwangsik Park(박영자),Sungpyo Kim(김성표) 환경독성보건학회 2016 한국독성학회 심포지움 및 학술발표회 Vol.2016 No.6

Study of Non-Newtonian fluid flow in porous media at core scale using analytical approach

Ryan Kurniawan Santoso,Iqbal Fauzi,Miftah Hidayat,Boni Swadesi,Bilal Maydika Aslam,Taufan Marhaendrajana 한국자원공학회 2018 Geosystem engineering Vol.21 No.1

Characterizing in situ polymer rheology in porous media is critical before further implementation of polymer injection in oilfield. Polymer as non-Newtonian fluid has unique behavior whose viscosity changes over various shear rate. This behavior creates unsuitable conditions which can lead to ineffective sweep efficiency improvement. The challenging issue in characterizing the in situ polymer rheology is how to construct the in situ Power Law model since the in situ viscosity cannot be measured directly. In this study, we use an analytical model to construct the in situ Power Law model. The model combines material balance equation, modified Darcy equation for non-Newtonian fluid flow, and equation of state. The model is solved for early (transient) time and late (steady-state) time. Coreflooding results in Berea Sandstone with 2000 and 500 ppm HPAM polymer injection are used for model’s simulations. Rheometer measurements are also used for comparison. The overall simulation results show there is no difference in flow behavior index between rheometer and porous media. The same fluid definitely gives the same flow behavior index through different measurement methods. However, there is significant difference in flow consistency index. It is caused by the effect of porous media’s tortuosity. The quantity of the skin parameter also depicts the thinning and thickening phenomena.

Novel insight into pressurization of the male and female urethra through application of a multi-channel fibre-optic pressure transducer: Proof of concept and validation

Ryan E. Stafford,John Arkwright,Phil G. Dinning,Wolbert van den Hoorn,Paul W. Hodges 대한비뇨의학회 2020 Investigative and Clinical Urology Vol.61 No.5

Purpose: To confirm feasibility of recording pressure along the length of the urethra using a multi-sensor fibre-optic pressure catheter; to identify the spatial and temporal features of changes in pressure along the urethra at sites related to specific striated pelvic floor muscles; and to investigate the relationship between urethral pressures and activation of individual pelvic floor muscles estimated from ultrasound imaging. Materials and Methods: Proof-of-concept study including one male (47 years old) and one female (33 years old). A multi-sensor fibre optic pressure catheter (10 mm sensor separation) was inserted into the urethra. Pressure data were recorded simultaneously with trans-perineal ultrasound imaging measures of pelvic floor muscle activity during sub-maximal and maximal voluntary contractions and evoked coughs. Results: Pressure changes along the urethra were recorded in all tasks in both participants. Face validity of interpretation of pressure measures with respect to individual muscles was supported by correlation with ultrasound-measured displacements induced by the relevant muscles. Onset of pressure increase occurred in a distal to proximal sequence in the urethra of the male but not the female during voluntary contraction. Peak urethral pressures varied in location, timing and amplitude between tasks. Evoked cough induced in the greatest urethral pressure increase across all tasks for both participants. Conclusions: The high spatial resolution pressure catheter provide viable and valid recordings of urethral pressure in a male and female. Data provide preliminary evidence of sex differences in spatial and temporal distribution of urethral pressure changes.

Community-based surveillance of Cryptosporidium in the indigenous community of Boliwong, Philippines: from April to December 2017

Ryan V. Labana,Julieta Z. Dungca,Veeranoot Nissapatorn 한국역학회 2018 Epidemiology and Health Vol.40 No.-

OBJECTIVES: For the first time, Boliwong, an indigenous community in the Philippines, was surveyed for the prevalence of Cryptosporidium from April to December 2017. METHODS: Cryptosporidium oocysts were detected in samples from the river, creek, and water pumps via immunomagnetic separation techniques, and from human and animal concentrated faecal samples using the modified Ziehl-Neelsen technique. RESULTS: Seven of the 24 water samples (29.2%) were positive for Cryptosporidium, with the highest concentration (0.8 oocyst/L) detected in the creek. Of 35 fecal samples from different animal groups, 8 (21.6%) were positive for Cryptosporidium oocysts. The highest intensity of oocyst shedding was detected in dogs (χ2=8.00). Of the 137 human fecal samples, 39 (28.5%) were infected with Cryptosporidium. In this study, 3 risk factors were found to be associated with infection: (1) location (crude odds ratio [cOR], 16.39; 95% confidence interval [CI], 2.11 to 127.41; p=0.008), (2) drinking water from the natural spring (cOR, 0.29; 95% CI, 0.11 to 0.82; p<0.05), and (3) using an open pit as a sanitary toilet facility (cOR, 2.44; 95% CI, 1.14 to 5.20; p<0.05). When the cOR was adjusted, using an open pit as a sanitary toilet facility remained a significant risk factor of infection (adjusted OR, 0.41; 95% CI, 0.19 to 0.90; p<0.05). CONCLUSIONS: There is a potentially emerging Cryptosporidium zoonosis in Boliwong, Lagawe, Philippines. It is recommended that the toilet facilities and the water system in the community be rehabilitated to avoid any possible disease outbreak. Health education is also needed in the community to maintain proper hygiene and sanitation practices.

Preoperative Narcotic Use, Impaired Ambulation Status, and Increased Intraoperative Blood Loss Are Independent Risk Factors for Complications Following Posterior Cervical Laminectomy and Fusion Surgery

Ryan K. Badiee,Andrew K. Chan,Joshua Rivera,Annette Molinaro,Brianna R. Doherty,K. Daniel Riew,Dean Chou,Praveen V. Mummaneni,Lee A. Tan 대한척추신경외과학회 2019 Neurospine Vol.16 No.3

Objective: This retrospective cohort study seeks to identify risk factors associated with complications following posterior cervical laminectomy and fusion (PCLF) surgery. Methods: Adults undergoing PCLF from 2012 through 2018 at a single center were identified. Demographic and radiographic data, surgical characteristics, and complication rates were compared. Multivariate logistic regression models identified independent predictors of complications following surgery. Results: A total of 196 patients met the inclusion criteria and were included in the study. The medical, surgical, and overall complication rates were 10.2%, 23.0%, and 29.1% respectively. Risk factors associated with medical complications in multivariate analysis included impaired ambulation status (odds ratio [OR], 2.27; p=0.02) and estimated blood loss over 500 mL (OR, 3.67; p=0.02). Multivariate analysis revealed preoperative narcotic use (OR, 2.43; p=0.02) and operative time (OR, 1.005; p=0.03) as risk factors for surgical complication, whereas antidepressant use was a protective factor (OR, 0.21; p=0.01). Overall complication was associated with preoperative narcotic use (OR, 1.97; p=0.04) and higher intraoperative blood loss (OR, 1.0007; p=0.03). Conclusion: Preoperative narcotic use and estimated blood loss predicted the incidence of complications following PCLF for CSM. Ambulation status was a significant predictor of the development of a medical complication specifically. These results may help surgeons in counseling patients who may be at increased risk of complication following surgery.