Room Temperature Dynamics of an Optically Addressable Single Spin in Hexagonal Boron Nitride.

Hexagonal boron nitride (h-BN) hosts pure single-photon emitters that have shown evidence of optically detected electronic spin dynamics. However, the electrical and chemical structures of these optically addressable spins are unknown, and the nature of their spin-optical interactions remains mysterious. Here, we use time-domain optical and microwave experiments to characterize a single emitter in h-BN exhibiting room temperature optically detected magnetic resonance. Using dynamical simulations, we constrain and quantify transition rates in the model, and we design optical control protocols that optimize the signal-to-noise ratio for spin readout. This constitutes a necessary step toward quantum control of spin states in h-BN.

Lanthanum Cerate Microspheres for Efficient Fluoride Removal from Wastewater.

The performance of lanthanum cerate microspheres (LCM) at removing fluoride was analyzed in batch experiments after they were synthesized via the hydrothermal strategy. The ball-shaped microsphere morphology of LCM is confirmed by SEM and TEM. The synthesized LCM adsorbent showed excellent adsorption capacity in the pH range 3.0-7.0, with the optimal pH range being 3.5-4.5. The Langmuir adsorption model was more appropriate than the Freundlich model for describing the adsorption isotherm. The LCM adsorbent exhibited a significantly higher Langmuir adsorption capacity of 104.83 mg/g at pH 4.0, surpassing that of any other reported adsorbent. We investigated the adsorption of fluoride under a variety of conditions, including the presence of distinct anions. Furthermore, testing the adsorbent in actual groundwater demonstrated its high effectiveness in removing fluoride. Different useful analytical techniques were used for measurements and to learn and deduce the adsorption mechanism.

Palladium-Catalyzed Chelation-Assisted Aldehyde C-H Bond Activation of Quinoline-8-carbaldehydes: Synthesis of Amides from Aldehydes with Anilines and Other Amines.

A palladium-catalyzed chelation-assisted direct aldehyde C-H bond amidation of quinoline-8-carbaldehydes with an amine was developed under mild reaction conditions. A wide range of amides were obtained in good to excellent yields from aldehyde with a variety of aniline derivatives and aliphatic amines. Our methodology was successfully applied to synthesize known DNA intercalating agents and can be easily scaled up to a gram scale.

Validating the Clinical Value of Temporal Artery Biopsy.

BACKGROUND: Giant cell arteritis (GCA) is a potentially devastating disease that may require treatment with high-dose steroids. Traditionally, diagnosis requires patients to meet at least 3 of 5 clinical criteria, one of which is a positive temporal artery biopsy (TAB). Vascular surgeons are often asked to perform TAB though it is not necessarily required for diagnosis or management. This study aimed to determine if TAB results altered management of patients with a concern for GCA by changing steroid use postoperatively in our health care system. METHODS: A retrospective review at a single-center tertiary care hospital was performed between 2007 and 2018. The inclusion criteria were patients greater than 18 years old with complete steroid treatment records who underwent a temporal artery biopsy due to concern for GCA. Steroid use and duration of treatment both pre- and post-operative were collected and analyzed. RESULTS: Eighty-three of 117 cases reviewed met inclusion criteria. Ninety-one percent (76) of patients had a negative biopsy. Twenty-nine percent (23) of negative biopsies met criteria for GCA prior to biopsy. Of those with a negative biopsy, steroids were continued in 68% (52) of patients after 30 days, 49% (37) after 90 days and 45% (34) after 180 days. Steroids were never started in 11% (6). One patient with a positive biopsy was discontinued on steroids due to intolerance. There was no statistically significant difference in duration of steroids between those with a positive and negative biopsy (average 610 and 787 days respectively; P = 0.682). Average follow up was 33 months. DISCUSSION: The duration of steroid use for patients with concern for GCA was not found to be altered by the performance of a TAB at our institution. Given the extremely low yield and absence of impact on steroid duration, TAB is not a useful diagnostic test at our institution. Similar reviews are recommended to determine the utility of TAB at other institutions that may differ in patient population or prescribing practices.

Outcomes Associated With Early vs. Delayed Invasive Strategy in NSTEMI Complicated by High Degree AV Block: A Nationwide Analysis.

Background: High degree atrioventricular block (HDAVB) is an uncommon complication of non-ST-segment elevation myocardial infarction (NSTEMI) that frequently necessitates pacemaker implantation. This contemporary analysis compares need for pacemaker implantation based on the timing of intervention in acute NSTEMI complicated by HDAVB.Methods: We used 2016-2017 National Inpatient Sample database to identify admissions with NSTEMI and HDAVB. Time to coronary intervention from initial admission was used to segregate the admissions into two groups: early invasive strategy (EIS) (<24 hours) and delayed invasive strategy (DIS) (>24 hours). Multivariable linear and logistic regression analysis was performed to compare in-hospital outcomes among the two groups.Results: Out of 949,984 NSTEMI related admissions, coexistent HDAVB was present in 0.7% (n=6725) patients. Amongst those, 55.61% (n=3740) hospitalizations included invasive intervention (EIS=1320, DIS=2420). Patients treated with EIS were younger (69.95 years vs. 72.38 years, P<0.05) and had concomitant cardiogenic shock. Contrarily, prevalence of chronic kidney disease, heart failure, and pulmonary hypertension was higher in DIS group. EIS was associated with lower length of stay and total hospitalization cost. In-hospital mortality and pacemaker implantation rates were not significantly different between patients in the EIS and DIS groups.Conclusion: HDAVB is a rare complication of NSTEMI and often associated with right coronary artery disease. The timing of revascularization does not appear to influence the rate of pacemaker placement in NSTEMI complicated by HDAVB. Further studies are needed to assess if early invasive strategy can benefit all patients with NSTEMI and HDAVB.

Mapping the immunogenic landscape of near-native HIV-1 envelope trimers in non-human primates.

The induction of broad and potent immunity by vaccines is the key focus of research efforts aimed at protecting against HIV-1 infection. Soluble native-like HIV-1 envelope glycoproteins have shown promise as vaccine candidates as they can induce potent autologous neutralizing responses in rabbits and non-human primates. In this study, monoclonal antibodies were isolated and characterized from rhesus macaques immunized with the BG505 SOSIP.664 trimer to better understand vaccine-induced antibody responses. Our studies reveal a diverse landscape of antibodies recognizing immunodominant strain-specific epitopes and non-neutralizing neo-epitopes. Additionally, we isolated a subset of mAbs against an epitope cluster at the gp120-gp41 interface that recognize the highly conserved fusion peptide and the glycan at position 88 and have characteristics akin to several human-derived broadly neutralizing antibodies.

Postdischarge venous thromboembolism following hospital admission with COVID-19.

The association of severe coronavirus disease 2019 (COVID-19) with an increased risk of venous thromboembolism (VTE) has resulted in specific guidelines for its prevention and management. The VTE risk appears highest in those with critical care admission. The need for postdischarge thromboprophylaxis remains controversial, which is reflected in conflicting expert guideline recommendations. Our local protocol provides thromboprophylaxis to COVID-19 patients during admission only. We report postdischarge VTE data from an ongoing quality improvement program incorporating root-cause analysis of hospital-associated VTE (HA-VTE). Following 1877 hospital discharges associated with COVID-19, 9 episodes of HA-VTE were diagnosed within 42 days, giving a postdischarge rate of 4.8 per 1000 discharges. Over 2019, following 18 159 discharges associated with a medical admission; there were 56 episodes of HA-VTE within 42 days (3.1 per 1000 discharges). The odds ratio for postdischarge HA-VTE associated with COVID-19 compared with 2019 was 1.6 (95% confidence interval, 0.77-3.1). COVID-19 hospitalization does not appear to increase the risk of postdischarge HA-VTE compared with hospitalization with other acute medical illness. Given that the risk-benefit ratio of postdischarge thromboprophylaxis remains uncertain, randomized controlled trials to evaluate the role of continuing thromboprophylaxis in COVID-19 patients following hospital discharge are required.

Temporizing stent graft for aortoenteric fistula with massive gastrointestinal hemorrhage.

OBJECTIVES: We present a case of a 59-year-old male with an actively bleeding aortoenteric fistula (AEF) that was temporized using an endovascular stent prior to staged open reconstruction. METHODS: Verbal informed consent was given by the patient's family for publication of this case report. The patient presented with pulseless electrical activity secondary to hemorrhagic shock due to a massive gastrointestinal bleed. His past surgical history included an aortobifemoral bypass (ABFB) that subsequently underwent extra-anatomic reconstruction with right axillofemoral artery bypass for right femoral infected pseudoaneurysm. Two months prior to presentation, he underwent a second revision with in-situ reconstruction for left limb graft infection. CTA now demonstrated actively bleeding AEF. He was emergently treated with endovascular stenting. Once stabilized, a two-stage revision with extra-anatomic bypass and aortic stump closure for management of his AEF was performed. RESULT: The patient was adequately stabilized using endovascular techniques followed by two-stage revision but unfortunately expired secondary to septic shock 20 days postoperatively. CONCLUSION: This case highlights the utility of endovascular stent graft to successfully obtain hemodynamic stability and optimization prior to open repair of AEFs.

Frugal Method of Notch Modification of Scleral Contact Lenses in the Setting of Complex Ocular Surface Anatomy.

ABSTRACT: Scleral contact lenses (ScCLs) have gained popularity as a treatment of refractive errors in patients with complex anterior segment pathology. Patients with mechanical abnormalities of the ocular surface may be unsuccessful with traditional ScCL fitting. Scleral contact lens modifications, such as notching and microvaulting, typically incur additional financial costs and require the services of professional laboratories. We describe a frugal method of ScCL notch modification that can be performed by a practitioner using readily available tools in a single office visit. Two patients with abnormal ocular surface anatomy were fit with the practitioner-modified ScCL and achieved successful visual rehabilitation. We offer this method as a potentially economical and effective technique to achieve successful ScCL fitting in this challenging patient population with pathologies that may preclude standard ScCL usage.

Adsorptive removal of methylene blue dye from aqueous streams using photocatalytic CuBTC/ZnO chitosan composites.

In this study, a CuBTC/ZnO chitosan composite was synthesized for the adsorptive removal of methylene blue dye from aqueous streams. Characterization techniques, namely, scanning electron microscopy, Brunauer-Emmett-Teller, Fourier transform infrared, X-ray diffraction, and thermogravimetric techniques, were used to characterize CuBTC, ZnO, and CuBTC/ZnO chitosan composites. The scanning electron microscopy images revealed the rough and porous structures of the CuBTC/ZnO chitosan composite. The composites were tested for the adsorption capacity and removal efficiency towards the methylene blue dye by varying adsorbent dosage, adsorbate concentration, pH, and contact time. The pseudo-second-order and Langmuir models were the best fit for the adsorption of methylene blue on CuBTC/ZnO chitosan composite beads, indicating that the adsorption was monolayer and chemical in nature. The equilibrium dose of the composites was 1.6 g L-1, and the contact time was 90 min with a removal efficiency of 98.75%. The maximum adsorption capacity was 50.07 mg g-1. Regeneration of the composites was performed to check the reusability of the synthesized CuBTC/ZnO chitosan composite beads. The active oxygenated species generated by the photocatalytic action of ZnO on the contaminated water was responsible for the degradation of methylene blue. The reported composite beads can be used for up to 5 cycles to remove methylene blue.

Investigation on the feasibility of recycled polyvinylidene difluoride polymer from used membranes for removal of methylene blue: experimental and DFT studies.

This study reports the feasibility of recycled polyvinylidene difluoride (PVDF) beads to decolourize methylene blue (MB) from aqueous streams. The beads were characterized using scanning electron microscopy (SEM), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FT-IR) for its morphological and structural analysis. The effect of various process parameters such as adsorbent dose, initial concentration, contact time, and pH was studied. The first principle density functional theory (DFT) calculations were performed to investigate the underlying mechanism behind the adsorption process. The MB dye adsorption on recycled PVDF beads followed the pseudo-second-order kinetics and Langmuir isotherm, indicating the adsorption was chemical and monolayer. The maximum adsorption capacity obtained was 27.86 mg g-1. The adsorption energy of MB-PVDF predicted from the DFT study was -64.7 kJ mol-1. The HOMO-LUMO energy gap of PVDF decreased from 9.42 eV to 0.50 eV upon interaction with MB dye due to the mixing of molecular orbitals. The DFT simulations showed that the interaction of the MB dye molecule was from the electronegative N atom of the MB dye molecule, implying that electrostatic interactions occurred between the recycled PVDF beads and the positively charged quaternary ammonium groups in MB dye. The present study demonstrates the potential of recycled PVDF beads for a low-cost dye removal technique from textile wastewater.

Off-treatment bone mineral density changes in postmenopausal women receiving anastrozole for 5 years: 7-year results from the IBIS-II prevention trial.

BACKGROUND: Anastrozole has been associated with substantial accelerated bone mineral density (BMD) loss during active treatment. METHODS: One thousand four hundred and ten women were included in a BMD substudy and stratified into three strata according to their baseline T-score at spine or femoral neck. The primary objective of this analysis was to investigate whether DXA BMD at the spine and hip changed two years after treatment cessation (between years 5 and 7) in those who did not receive risedronate. RESULTS: Five- and seven-year BMD data were available for a total of 528 women who did not receive risedronate. In women with normal BMD at baseline, an increase in BMD at the lumbar spine after anastrozole withdrawal was observed 1.25% (95% CI 0.73 to 1.77) (P = 0.0004), which was larger than in those on placebo (0.14% (-0.29 to 0.56))). At the hip, BMD remained unchanged between years 5 and 7 for those previously on anastrozole but continued to a decrease in those who had been randomised to placebo (-1.35% (-1.70 to -0.98)). CONCLUSIONS: These are the first results reporting BMD changes after stopping anastrozole in a breast cancer prevention setting. Our results show that the negative effects of anastrozole on BMD in the preventive setting are partially reversible.

COVID-19 in Immunocompromised Cancer Patients: A Case Series and Review of the Literature.

The global pandemic of the novel coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has presented newfound challenges to the oncology community regarding management of disease progression in immunocompromised and cancer patients. Further, the large influx of COVID-19 patients has overwhelmed healthcare facilities, limited access to intensive care unit beds and ventilators, and canceled elective surgeries causing disruptions to the cancer care continuum and re-organization of oncological care. While it is known that the potential threat of infection is greatest in elderly patients (>60 years of age) and patients with underlying comorbidities, there is still insufficient data to determine the risk of COVID-19 in cancer patients. Given the immunosuppressive status in cancer patients arising from chemotherapy and other comorbidities, management of COVID-19 in this patient population carries a unique set of challenges. We report three cases of COVID-19 in immunocompromised cancer patients and discuss the challenges in preventing, diagnosing, and treating this vulnerable group.

Successful Transfemoral Transcatheter Aortic Valve Replacement in a Patient with Double Aortic Arch: An Interesting Imaging Case.

Transcatheter aortic valve replacement (TAVR) has become a mainstay of treatment in the management of severe aortic stenosis. It is a challenging procedure that requires expertise in obtaining proper access, delivery of catheters to and beyond the aortic valve, and finally accurate deployment of the aortic bioprosthesis. Patients with aortic anomalies portend an added challenge in performing TAVR procedures. We present the case of a patient incidentally found to have a right dominant double aortic arch who underwent successful TAVR for severe aortic stenosis.

Experimental Observation of Coherent-Information Superadditivity in a Dephrasure Channel.

We present an experimental approach to construct a dephrasure channel that contains both dephasing and erasure noises and can be used as an efficient tool to study the superadditivity of coherent information. Using a three-fold dephrasure channel, the superadditivity of coherent information is observed, and a substantial gap is found between the zero single-letter coherent information and zero quantum capacity. Particularly, we find that, when the coherent information of n channel uses is zero, with a larger number of channel uses the quantum capacity becomes positive. These phenomena exhibit a more obvious superadditivity of coherent information than previous works and demonstrate a higher threshold for nonzero quantum capacity. Such novel channels built in our experiment also can provide a useful platform to study the nonadditive properties of coherent information and quantum channel capacity.

Progress in the monitoring of direct oral anticoagulant therapy.

The availability of direct oral anticoagulants (DOACs) has led to a paradigm shift in the field of anticoagulation, with DOACs increasingly being prescribed for patients in preference to vitamin K antagonists and low molecular weight heparin. Despite good experience with the use of these agents at fixed doses, there are clinical scenarios where monitoring is recommended. Data from phase III studies of the DOACs and small real-world studies suggest a relationship between DOAC concentration and clinical events. The DOACs have differing impacts on the common tests of haemostasis and it is important that clinicians are familiar with the sensitivity of the reagents used in their laboratory to individual DOACs. The specific DOAC drug concentrations can be assayed in the laboratory, when required, to guide appropriate clinical decision-making. Studies from the real world with sufficient numbers evaluating the association of DOAC concentrations with outcomes should be a research priority in order to understand if we could do better through dose individualisation.

Contemporary practice pattern of revascularization in a large tertiary care referral center in non-ST elevation myocardial infarction: A propensity-matched 10-year experience.

OBJECTIVES: We sought to compare the effects of early versus delayed percutaneous coronary intervention (PCI) on the outcomes at 1 year in patients presenting with non-ST-segment elevation myocardial infarction (NSTEMI). BACKGROUND: Prompt reperfusion in NSTEMI remains controversial. Randomized studies have shown conflicting results regarding the benefits of early intervention versus delayed intervention (defined as intervention performed within 24 hr vs. 24-72 hr of presentation, respectively). This study was conducted to determine the clinical outcomes post PCI in a large tertiary care center. METHODS: A propensity-matched group of 1,640 NSTEMI patients [62.4% males (n = 1,023), median age 65 years] was studied for a composite of death, myocardial infarction (MI), stroke, and heart failure in 1 year as a primary endpoint after PCI. Patients were divided into an early intervention group (EIG) and delayed intervention group (DIG). Timing of PCI was determined by the treating interventional cardiologist. RESULTS: The primary outcome was significantly lower in the EIG than DIG (20.4% vs. 24.9%, P = 0.029), which was mainly derived from mortality benefit in the EIG. There was no difference in occurrence of death, MI, stroke, or heart failure between the groups at 30 days. CONCLUSIONS: An earlier PCI in patients with NSTEMI is associated with a significant reduction in the composite outcome of death, MI, heart failure, or stroke at 1 year compared with delayed PCI. Based on this large cohort of patients from a real-world referral center, contemporary reperfusion practices in NSTEMI may need to be re-examined with a bias toward early intervention.

What are the difficulties in conducting randomised controlled trials of thromboprophylaxis in myeloma patients and how can we address these? Lessons from apixaban versus LMWH or aspirin as thromboprophylaxis in newly diagnosed multiple myeloma (TiMM) feasibility clinical trial.

Routine thromboprophylaxis (TP) in newly-diagnosed multiple myeloma (NDMM) patients comprises either aspirin for standard risk patients or low molecular weight heparin for high risk patients. Studies using DOACs in cancer patients include few with myeloma. The aim of this feasibility clinical trial was to establish the foundations for creating a multicentre trial and identify any safety concerns with apixaban. Patient perspectives were sought. NDMM patients were stratified according to VTE risk and randomised to either standard TP or apixaban 2.5 mg BD and reviewed every 3 weeks throughout their chemotherapy. Two focus groups were carried out on 2 occasions at King's College Hospital and Guy's Hospital, London. Each lasted an hour, were recorded, transcribed and themes explored using NVivo 11. Ten patients were recruited, 2 considered high risk and received apixaban and 8 standard risk; 4 randomised to aspirin and 4 to apixaban. Five patients and 2 carers participated in the focus groups. There were no major bleeding or VTE events. Patients were not aware of the thrombotic risk associated with cancer. There is a lack of both written and verbal information on this topic. Myeloma patients were happy to be included in more than one trial simultaneously. Our study provides information on the difficulties facing physicians and patients on obtaining evidence of the safety of DOACs in the context of myeloma. Despite patients being happy to co-recruit into thromboprophylaxis trials along with chemotherapy trials this is not current practice.EudraCT Number: 2015-002668-18.