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The hole-injection and recombination photophysics for NiO sensitized with RuP ([RuII(bpy)2(4,4′-(PO3H2)2-bpy)]2+) are explored. Ultrafast transient absorption (TA) measurements performed with an external electrochemical bias reveal the efficiency for productive hole-injection, that is, quenching of the dye excited state that results in a detectable charge-separated electron–hole pair, is linearly dependent on the electronic occupation of intragap states in the NiO film. Population of these states via a negative applied potential increases the efficiency from 0% to 100%. The results indicate the primary loss mechanism for dye-sensitized NiO is rapid nongeminate recombination enabled by the presence of latent holes in the surface of the NiO film. Our findings suggest a new design paradigm for NiO photocathodes and devices centered on the avoidance of this recombination pathway.

Electronic energy transfer plays an important role in many types of organic electronic devices. Förster-type theories of exciton diffusion provide a way to calculate diffusion constants and lengths, but their applicability to amorphous polymer systems must be evaluated. In this paper, the perylenediimide dye Lumogen Red in a poly(methyl methacrylate) host matrix is used to test theories of exciton motion over Lumogen Red concentrations (CLR’s) ranging from 1 × 10−4to 5 × 10−2M. Two experimental quantities are measured. First, time-resolved anisotropy decays in films containing only Lumogen Red provide an estimate of the initial energy transfer rate from the photoexcited molecule. Second, the Lumogen Red lifetime decays in mixed systems where the dyes Malachite Green and Rhodamine 700 act as energy acceptors are measured to estimate the diffusive quenching of the exciton. From the anisotropy measurements, it is found that theory accurately predicts both the CLR−2concentration dependence of the polarization decay time τpol, as well as its magnitude to within 30%. The theory also predicts that the diffusive quenching rate is proportional to CLRα, where α ranges between 1.00 and 1.33. Experimentally, it is found that α = 1.1 ± 0.2 when Malachite Green is used as an acceptor, and α = 1.2 ± 0.2 when Rhodamine 700 is the acceptor. On the basis of the theory that correctly describes the anisotropy data, the exciton diffusion constant is projected to be 4−9 nm2/ns. By use of several different analysis methods for the quenching data, the experimental diffusion constant is found to be in the range of 0.32−1.20 nm2/ns. Thus the theory successfully describes the early time anisotropy data but fails to quantitatively describe the quenching experiments which are sensitive to motion on longer time scales. The data are consistent with the idea that orientational and energetic disorder leads to a time-dependent exciton migration rate, suggesting that simple diffusion models cannot accurately describe exciton motion within this system.

Visible-light-driven water splitting was investigated in a dye sensitized photoelectrosynthesis cell (DSPEC) based on a photoanode with a phosphonic acid-derivatized donor−π–acceptor (D−π–A) organic chromophore, 1, and the water oxidation catalyst [Ru(bda)(4-O(CH2)3P(O3H2)2-pyr)2], 2, (pyr = pyridine; bda = 2,2′-bipyridine-6,6′-dicarboxylate). The photoanode was prepared by using a layering strategy beginning with the organic dye anchored to an FTO|core/shell electrode, atomic layer deposition (ALD) of a thin layer (<1 nm) of TiO2, and catalyst binding through phosphonate linkage to the TiO2layer. Device performance was evaluated by photocurrent measurements for core/shell photoanodes, with either SnO2or nanoITO core materials, in acetate-buffered, aqueous solutions at pH 4.6 or 5.7. The absolute magnitudes of photocurrent changes with the core material, TiO2spacer layer thickness, or pH, observed photocurrents were 2.5-fold higher in the presence of catalyst. The results of transient absorption measurements and DFT calculations show that electron injection by the photoexcited organic dye is ultrafast promoted by electronic interactions enabled by orientation of the dye’s molecular orbitals on the electrode surface. Rapid injection is followed by recombination with the oxidized dye which is 95% complete by 1.5 ns. Although chromophore decomposition limits the efficiency of the DSPEC devices toward O2production, the flexibility of the strategy presented here offers a new approach to photoanode design.

Background:The incidence of tuberculosis (TB) in end-stage renal disease is significantly higher than that in the general population. Among those with kidney dysfunction, anti-TB treatment is associated with increased side effects, but the effect on healthcare utilization is unknown. Methods/Aim:To assess patient-reported symptoms, adverse effects and describe changes in healthcare utilization patterns during treatment for TB, we conducted a case series (n = 12) of patients receiving maintenance hemodialysis (HD) from Mayo Clinic Dialysis Services and concurrent drug therapy for TB from January 2002 through May 2014. Healthcare utilization (hospitalizations and emergency department (ED) visits independent of hospital admission) was compared before and during treatment. Results:Patients were treated for latent (n = 7) or active (n = 5) TB. The majority of patients with latent disease were treated with isoniazid (n = 5, 71%), while active-disease patients received a 4-drug regimen. Adverse effects were reported in 83% of patients. Compared to measurements prior to drug initiation, serum albumin and dialysis weights were similar at 3 months. Commonly reported anti-TB drug toxicities were described. More than half (58%) of the patients were hospitalized at least once. No ED or hospital admissions occurred in the period prior to drug therapy, but healthcare utilization increased during treatment in the latent disease group (hospitalization rate per person-month: pre 0 vs. post 1). Conclusions:Among HD patients, anti-TB therapy is associated with frequently reported symptoms and increased healthcare utilization. Among this subset, patients receiving treatment for latent disease may be those with greatest increase in healthcare use. Careful monitoring and early complication detection may help optimize medication adherence and minimize hospitalizations.

The timely triage of pregnant patients presenting for emergent care is an important factor for decreasing maternal morbidity and mortality. The Maternal-Fetal Triage Index (MFTI) is an assessment tool developed by the Association of Women's Health, Obstetric and Neonatal Nurses in 2014 and endorsed by the American College of Obstetricians and Gynecologists (ACOG) in 2016 for triaging obstetrical patients presenting for emergent care. The Joint Commission has identified response time to severe hypertension, or preeclampsia, as one of its elements of performance. The aim of this study was to examine the management of women with severe hypertension before and after the implementation of MFTI.This was a prospective, observational study at a county-supported, urban academic hospital, serving medically indigent women. Included were women at ≥24 weeks of gestation, who presented in the hospital's obstetric triage unit with severe preeclampsia diagnosed by severe hypertension. Severe hypertension was defined as blood pressure (BP) ≥160/110 mm Hg. Excluded were those who were not admitted for delivery at the time of presentation. Patients with BP ≥160/110 mm Hg were given magnesium sulfate (MgSO4) prophylaxis and treated with intravenous hydralazine, labetalol, or immediate-release nifedipine. Patients admitted before the implementation of MFTI (between January 1, 2019, and December 31, 2019) represented epoch 1 of the cohort. Those admitted after MFTI implementation (between March 1, 2021, and September 30, 2021) made up epoch 2. Nursing staff used the criteria outlined in the MFTI to prioritize patient acuity. A 1 score is the highest priority, and a 5 score is the lowest priority. The primary outcome was the time interval to evaluate and manage women with severe hypertension before and after MFTI implementation, as measured by arrival time to provider assessment, arrival time to MgSO4prophylaxis, and arrival time to the administration of antihypertensive medications.There were 370 patients in epoch 1, before MFTI implementation, and 254 patients in epoch 2, after implementation. The time from arrival to provider assessment improved significantly from epoch 1 to epoch 2 (median time: 44 minutes [interquartile range, 0–65 minutes] vs 17 minutes [IQR, 0–39 minutes], respectively; P< 0.001). The time from arrival to MgSO4prophylaxis also improved (160 minutes [IQR, 109–256 minutes] vs 126 minutes [IQR, 85–258 minutes], respectively; P= 0.001). There was a decrease in the time from arrival to administration of antihypertensive medications between the 2 time frames (101 minutes [IQR, 61–177 minutes] in epoch 1 vs 66 minutes [IQR, 35–203 minutes] in epoch 2; P< 0.001). In a separate analysis, race and ethnicity did not factor into the performance of MFTI.Overall, there was an improvement in the evaluation and management of pregnant women with severe hypertension after the implementation of MFTI, regardless of race and ethnicity. Timely identification and management of this high-risk population may improve maternal morbidity and mortality.

IMPORTANCE: For patients with chronic kidney disease (CKD), hyperkalemia is common, associated with fatal arrhythmias, and often asymptomatic, while guideline-directed monitoring of serum potassium is underused. A deep-learning model that enables noninvasive hyperkalemia screening from the electrocardiogram (ECG) may improve detection of this life-threatening condition. OBJECTIVE: To evaluate the performance of a deep-learning model in detection of hyperkalemia from the ECG in patients with CKD. DESIGN, SETTING, AND PARTICIPANTS: A deep convolutional neural network (DNN) was trained using 1 576 581 ECGs from 449 380 patients seen at Mayo Clinic, Rochester, Minnesota, from 1994 to 2017. The DNN was trained using 2 (leads I and II) or 4 (leads I, II, V3, and V5) ECG leads to detect serum potassium levels of 5.5 mEq/L or less (to convert to millimoles per liter, multiply by 1) and was validated using retrospective data from the Mayo Clinic in Minnesota, Florida, and Arizona. The validation included 61 965 patients with stage 3 or greater CKD. Each patient had a serum potassium count drawn within 4 hours after their ECG was recorded. Data were analyzed between April 12, 2018, and June 25, 2018. EXPOSURES: Use of a deep-learning model. MAIN OUTCOMES AND MEASURES: Area under the receiver operating characteristic curve (AUC) and sensitivity and specificity, with serum potassium level as the reference standard. The model was evaluated at 2 operating points, 1 for equal specificity and sensitivity and another for high (90%) sensitivity. RESULTS: Of the total 1 638 546 ECGs, 908 000 (55%) were from men. The prevalence of hyperkalemia in the 3 validation data sets ranged from 2.6% (n = 1282 of 50 099; Minnesota) to 4.8% (n = 287 of 6011; Florida). Using ECG leads I and II, the AUC of the deep-learning model was 0.883 (95% CI, 0.873-0.893) for Minnesota, 0.860 (95% CI, 0.837-0.883) for Florida, and 0.853 (95% CI, 0.830-0.877) for Arizona. Using a 90% sensitivity operating point, the sensitivity was 90.2% (95% CI, 88.4%-91.7%) and specificity was 63.2% (95% CI, 62.7%-63.6%) for Minnesota; the sensitivity was 91.3% (95% CI, 87.4%-94.3%) and specificity was 54.7% (95% CI, 53.4%-56.0%) for Florida; and the sensitivity was 88.9% (95% CI, 84.5%-92.4%) and specificity was 55.0% (95% CI, 53.7%-56.3%) for Arizona. CONCLUSIONS AND RELEVANCE: In this study, using only 2 ECG leads, a deep-learning model detected hyperkalemia in patients with renal disease with an AUC of 0.853 to 0.883. The application of artificial intelligence to the ECG may enable screening for hyperkalemia. Prospective studies are warranted.

We report on the chemical lithiation of long microscale helices composed of densely packed amorphous silicon (aSi) nanofibrils, fabricated by glancing angle deposition (GLAD) through e-beam evaporation. In situ electron microscopy and companion finite element modeling demonstrate that the nanofibrillar structure of the aSi helices allows for 2 orders of magnitude faster effective rates for Li diffusion (D0= 10–10cm2/s) compared to solid aSi nanowires, while also averting fragmentation during lithiation. More importantly, it is shown that specific helical geometries can accommodate large, lithium-induced, volumetric expansions without shape distortion. A major advantage of the helical nanostructures is that the compressive force generated due to lithiation-induced expansion is an order of magnitude smaller than in straight nanocolumns that permanently buckle during lithiation. Thus, GLAD-fabricated films composed of dense periodic microscale helices with properly designed coil geometries are highly suitable for robust, high-capacity Li+anodes.

We report the case of an 8-year-old patient with a history of nephrotic syndrome, who presented to the emergency department with right foot pain. The patient's mother described intermittent pain that woke her son from sleep and was accompanied by the foot turning purple and becoming cold to touch. Physical examination revealed capillary refill of over 10 seconds in the right and less than 2 seconds in the left foot. Ankle-brachial indices (ABIs) were 0.0 on the right and 0.96 on the left. The patient was admitted and started on therapeutic intravenous heparin. After consultation with his parents, right lower extremity angiography and thrombolysis was performed over 2 days. He subsequently underwent fasciotomy and amputation of the tip of all 5 toes. Eighteen months later, there is no leg length discrepancy, he is walking with foot inserts and has normal ABIs bilaterally.