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1.
Risk Anal ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664225

RESUMEN

A comparative assessment of the risks of the three current wastewater effluent disposal options and three other potential options was conducted for Southeast Florida communities. The question was how the risk to humans from the use of potable reuse compares to the other five available wastewater disposal alternatives. The need for this type of risk assessment is due to the potential to use potable reuse as a water supply and the potential resistance from the public as a result of such a proposal. Water quality data relevant to disposal of wastewater treatment plant effluent from South Florida utilities along with water quality data on the receiving waters and drinking water standards were obtained for the project. The comparison of the public health risks associated with these disposal alternatives indicated that health risks associated with deep wells and direct potable reuse were generally lower than those of the other alternatives.

2.
Open Forum Infect Dis ; 11(3): ofae096, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38456194

RESUMEN

Background: Community-acquired pneumonia is a well-studied condition; yet, in the urgent care setting, patient characteristics and adherence to guideline-recommended care are poorly described. Within Intermountain Health, a nonprofit integrated US health care system based in Utah, more patients present to urgent care clinics (UCCs) than emergency departments (EDs) for pneumonia care. Methods: We performed a retrospective cohort study 1 January 2019 through 31 December 2020 in 28 UCCs within Utah. We extracted electronic health record data for patients aged ≥12 years with ICD-10 pneumonia diagnoses entered by the bedside clinician, excluding patients with preceding pneumonia within 30 days or missing vital signs. We compared UCC patients with radiographic pneumonia (n = 4689), without radiographic pneumonia (n = 1053), without chest imaging (n = 1472), and matched controls with acute cough/bronchitis (n = 15 972). Additional outcomes were 30-day mortality and the proportion of patients with ED visits or hospital admission within 7 days after the index encounter. Results: UCC patients diagnosed with pneumonia and possible/likely radiographic pneumonia by radiologist report had a mean age of 40 years and 52% were female. Almost all patients with pneumonia (93%) were treated with antibiotics, including those without radiographic confirmation. Hospital admissions and ED visits within 7 days were more common in patients with radiographic pneumonia vs patients with "unlikely" radiographs (6% vs 2% and 10% vs 6%, respectively). Observed 30-day all-cause mortality was low (0.26%). Patients diagnosed without chest imaging presented similarly to matched patients with cough/acute bronchitis. Most patients admitted to the hospital the same day after the UCC visit (84%) had an interim ED encounter. Pneumonia severity scores (pneumonia severity index, electronic CURB-65, and shock index) overestimated patient need for hospitalization. Conclusions: Most UCC patients with pneumonia were successfully treated as outpatients. Opportunities to improve care include clinical decision support for diagnosing pneumonia with radiographic confirmation and development of pneumonia severity scores tailored to the UCC.

4.
Inflamm Bowel Dis ; 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38372691

RESUMEN

BACKGROUND: Pediatric inflammatory bowel disease (pIBD) incidence has increased over the last 25 years. We aim to report contemporaneous trends across the South West United Kingdom. METHODS: Data were provided from centers covering the South West United Kingdom (Bristol, Oxford, Cardiff, Exeter, and Southampton), with a total area at-risk population (<18 years of age) of 2 947 534. Cases were retrieved from 2013 to 2022. Incident rates were reported per 100 000 at-risk population, with temporal trends analyzed through correlation. Subgroup analysis was undertaken for age groups (0-6, 6-11, and 12-17 years of age), sex, and disease subtype. Choropleth maps were created for local districts. RESULTS: In total, 2497 pIBD cases were diagnosed between 2013 and 2022, with a mean age of 12.6 years (38.7% female). Diagnosis numbers increased from 187 to 376, with corresponding incidence rates of 6.0 per 100 000 population per year (2013) to 12.4 per 100 000 population per year (2022) (b = 0.918, P < .01). Female rates increased from 5.1 per 100 000 population per year in 2013 to 11.0 per 100 000 population per year in 2022 (b = 0.865, P = .01). Male rates increased from 5.7 per 100 000 population per year to 14.4 per 100 000 population per year (b = 0.832, P = .03). Crohn's disease incidence increased from 3.1 per 100 000 population per year to 6.3 per 100 000 population per year (b = 0.897, P < .01). Ulcerative colitis increased from 2.3 per 100 000 population per year to 4.3 per 100 000 population per year (b = 0.813, P = .04). Inflammatory bowel disease unclassified also increased, from 0.6 per 100 000 population per year to 1.8 per 100 000 population per year (b = 0.851, P = .02). Statistically significant increases were seen in those ≥12 to 17 years of age, from 11.2 per 100 000 population per year to 24.6 per 100 000 population per year (b = 0.912, P < .01), and the 7- to 11-year-old age group, with incidence rising from 4.4 per 100 000 population per year to 7.6 per 100 000 population per year (b = 0.878, P = .01). There was no statistically significant increase in very early onset inflammatory bowel disease (≤6 years of age) (b = 0.417, P = .231). CONCLUSIONS: We demonstrate significant increases in pIBD incidence across a large geographical area including multiple referral centers. Increasing incidence has implications for service provision for services managing pIBD.


Incidence of inflammatory bowel disease continues to increase in childhood, particularly in older children. This is demonstrated in a contemporary dataset collected over a 10-year period, and covering an at-risk population of nearly 3 000 000. These data have significant implications for service provision.

5.
J Med Ethics ; 2024 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-38184371

RESUMEN

The UK government has recently committed to adopting a new policy-dubbed 'Martha's Rule'-which has been characterised as providing patients the right to rapidly access a second clinical opinion in urgent or contested cases. Support for the rule emerged following the death of Martha Mills in 2021, after doctors failed to admit her to intensive care despite concerns raised by her parents. We argue that framing this issue in terms of patient rights is not productive, and should be avoided. Insofar as the ultimate goal of Martha's Rule is the provision of a clinical service that protects patient safety, an approach that focuses on the obligations of the health system-rather than the individual rights of patients-will better serve this goal. We outline an alternative approach that situates rapid clinical review as part of a suite of services aimed at enhancing and protecting patient care. This approach would make greater progress towards addressing the difficult systemic issues that Martha's Rule does not, while also better engaging with the constraints of clinical practice.

6.
Nat Commun ; 14(1): 8202, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38081844

RESUMEN

The charge density wave material 1T-TaS2 exhibits a pulse-induced insulator-to-metal transition, which shows promise for next-generation electronics such as memristive memory and neuromorphic hardware. However, the rational design of TaS2 devices is hindered by a poor understanding of the switching mechanism, the pulse-induced phase, and the influence of material defects. Here, we operate a 2-terminal TaS2 device within a scanning transmission electron microscope at cryogenic temperature, and directly visualize the changing charge density wave structure with nanoscale spatial resolution and down to 300 µs temporal resolution. We show that the pulse-induced transition is driven by Joule heating, and that the pulse-induced state corresponds to the nearly commensurate and incommensurate charge density wave phases, depending on the applied voltage amplitude. With our in operando cryogenic electron microscopy experiments, we directly correlate the charge density wave structure with the device resistance, and show that dislocations significantly impact device performance. This work resolves fundamental questions of resistive switching in TaS2 devices, critical for engineering reliable and scalable TaS2 electronics.

9.
Nat Commun ; 14(1): 4803, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37558697

RESUMEN

The layer stacking order in 2D materials strongly affects functional properties and holds promise for next-generation electronic devices. In bulk, octahedral MoTe2 possesses two stacking arrangements, the ferroelectric Weyl semimetal Td phase and the higher-order topological insulator 1T' phase. However, in thin flakes of MoTe2, it is unclear if the layer stacking follows the Td, 1T', or an alternative stacking sequence. Here, we use atomic-resolution scanning transmission electron microscopy to directly visualize the MoTe2 layer stacking. In thin flakes, we observe highly disordered stacking, with nanoscale 1T' and Td domains, as well as alternative stacking arrangements not found in the bulk. We attribute these findings to intrinsic confinement effects on the MoTe2 stacking-dependent free energy. Our results are important for the understanding of exotic physics displayed in MoTe2 flakes. More broadly, this work suggests c-axis confinement as a method to influence layer stacking in other 2D materials.

10.
J Am Chem Soc ; 145(14): 8218-8230, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36996286

RESUMEN

The discovery of novel large band gap two-dimensional (2D) materials with good stability and high carrier mobility will innovate the next generation of electronics and optoelectronics. A new allotrope of 2D violet phosphorus P11 was synthesized via a salt flux method in the presence of bismuth. Millimeter-sized crystals of violet-P11 were collected after removing the salt flux with DI water. From single-crystal X-ray diffraction, the crystal structure of violet-P11 was determined to be in the monoclinic space group C2/c (no. 15) with unit cell parameters of a = 9.166(6) Å, b = 9.121(6) Å, c = 21.803(14)Å, ß = 97.638(17)°, and a unit cell volume of 1807(2) Å3. The structure differences between violet-P11, violet-P21, and fibrous-P21 are discussed. The violet-P11 crystals can be mechanically exfoliated down to a few layers (∼6 nm). Photoluminescence and Raman measurements reveal the thickness-dependent nature of violet-P11, and exfoliated violet-P11 flakes were stable in ambient air for at least 1 h, exhibiting moderate ambient stability. The bulk violet-P11 crystals exhibit excellent stability, being stable in ambient air for many days. The optical band gap of violet-P11 bulk crystals is 2.0(1) eV measured by UV-Vis and electron energy-loss spectroscopy measurements, in agreement with density functional theory calculations which predict that violet-P11 is a direct band gap semiconductor with band gaps of 1.8 and 1.9 eV for bulk and monolayer, respectively, and with a high carrier mobility. This band gap is the largest among the known single-element 2D layered bulk crystals and thus attractive for various optoelectronic devices.

11.
Angew Chem Int Ed Engl ; 62(23): e202302152, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36972027

RESUMEN

We report a ternary hybrid photocatalyst architecture with tailored interfaces that boost the utilization of solar energy for photochemical CO2 reduction by synergizing electron and heat flows in the photocatalyst. The photocatalyst comprises cobalt phthalocyanine (CoPc) molecules assembled on multiwalled carbon nanotubes (CNTs) that are decorated with nearly monodispersed cadmium sulfide quantum dots (CdS QDs). The CdS QDs absorb visible light and generate electron-hole pairs. The CNTs rapidly transfer the photogenerated electrons from CdS to CoPc. The CoPc molecules then selectively reduce CO2 to CO. The interfacial dynamics and catalytic behavior are clearly revealed by time-resolved and in situ vibrational spectroscopies. In addition to serving as electron highways, the black body property of the CNT component can create local photothermal heating to activate amine-captured CO2 , namely carbamates, for direct photochemical conversion without additional energy input.

12.
Adv Mater ; 35(13): e2208965, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36745845

RESUMEN

The increasing resistance of copper (Cu) interconnects for decreasing dimensions is a major challenge in continued downscaling of integrated circuits beyond the 7 nm technology node as it leads to unacceptable signal delays and power consumption in computing. The resistivity of Cu increases due to electron scattering at surfaces and grain boundaries at the nanoscale. Topological semimetals, owing to their topologically protected surface states and suppressed electron backscattering, are promising candidates to potentially replace current Cu interconnects. Here, we report the unprecedented resistivity scaling of topological metal molybdenum phosphide (MoP) nanowires, and it is shown that the resistivity values are superior to those of nanoscale Cu interconnects <500 nm2 cross-section areas. The cohesive energy of MoP suggests better stability against electromigration, enabling a barrier-free design . MoP nanowires are more resistant to surface oxidation than the 20 nm thick Cu. The thermal conductivity of MoP is comparable to those of Ru and Co. Most importantly, it is demonstrated that the dimensional scaling of MoP, in terms of line resistance versus total cross-sectional area, is competitive to those of effective Cu with barrier/liner and barrier-less Ru, suggesting MoP is an attractive alternative for the scaling challenge of Cu interconnects.

13.
Nat Nanotechnol ; 18(2): 160-167, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36536043

RESUMEN

Electrochemistry can provide an efficient and sustainable way to treat environmental waters polluted by chlorinated organic compounds. However, the electrochemical valorization of 1,2-dichloroethane (DCA) is currently challenged by the lack of a catalyst that can selectively convert DCA in aqueous solutions into ethylene. Here we report a catalyst comprising cobalt phthalocyanine molecules assembled on multiwalled carbon nanotubes that can electrochemically decompose aqueous DCA with high current and energy efficiencies. Ethylene is produced at high rates with unprecedented ~100% Faradaic efficiency across wide electrode potential and reactant concentration ranges. Kinetic studies and density functional theory calculations reveal that the rate-determining step is the first C-Cl bond breaking, which does not involve protons-a key mechanistic feature that enables cobalt phthalocyanine/carbon nanotube to efficiently catalyse DCA dechlorination and suppress the hydrogen evolution reaction. The nanotubular structure of the catalyst enables us to shape it into a flow-through electrified membrane, which we have used to demonstrate >95% DCA removal from simulated water samples with environmentally relevant DCA and electrolyte concentrations.

14.
ACS Nanosci Au ; 2(5): 433-439, 2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36281254

RESUMEN

MXenes are a growing family of 2D transition-metal carbides and nitrides, which display excellent performance in myriad of applications. Theoretical calculations suggest that manipulation of the MXene surface termination (such as =O or -F) could strongly alter their functional properties; however, experimental control of the MXene surface termination is still in the developmental stage. Here, we demonstrate that annealing MXenes in an Ar + O2 low-power plasma results in increased =O functionalization with minimal formation of secondary phases. We apply this method to two MXenes, Ti2CT x and Mo2TiC2T x (T x represents the mixed surface termination), and show that in both cases, the increased =O content increases the electrical resistance and decreases the surface transition-metal's electron count. For Mo2TiC2O x , we show that the O content can be reversibly altered through successive vacuum and plasma annealing. This work provides an effective way to tune MXene surface functionalization, which may unlock exciting surface-dependent properties.

16.
Nature ; 606(7916): 896-901, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35676485

RESUMEN

The observation of the Higgs boson solidified the standard model of particle physics. However, explanations of anomalies (for example, dark matter) rely on further symmetry breaking, calling for an undiscovered axial Higgs mode1. The Higgs mode was also seen in magnetic, superconducting and charge density wave (CDW) systems2,3. Uncovering the vector properties of a low-energy mode is challenging, and requires going beyond typical spectroscopic or scattering techniques. Here we discover an axial Higgs mode in the CDW system RTe3 using the interference of quantum pathways. In RTe3 (R = La, Gd), the electronic ordering couples bands of equal or different angular momenta4-6. As such, the Raman scattering tensor associated with the Higgs mode contains both symmetric and antisymmetric components, which are excited via two distinct but degenerate pathways. This leads to constructive or destructive interference of these pathways, depending on the choice of the incident and Raman-scattered light polarization. The qualitative behaviour of the Raman spectra is well captured by an appropriate tight-binding model, including an axial Higgs mode. Elucidation of the antisymmetric component is direct evidence that the Higgs mode contains an axial vector representation (that is, a pseudo-angular momentum) and hints that the CDW is unconventional. Thus, we provide a means for measuring quantum properties of collective modes without resorting to extreme experimental conditions.

17.
ACS Appl Mater Interfaces ; 14(3): 3980-3990, 2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-35014781

RESUMEN

Transition metal phosphorus trisulfide materials have received considerable research interest since the 1980-1990s as they exhibit promising energy conversion and storage properties. However, the mechanistic insights into Li-ion storage in these materials are poorly understood to date. Here, we explore the lithiation of NiPS3 material by employing in situ pair-distribution function analysis, Monte Carlo molecular dynamics calculations, and a series of ex situ characterizations. Our findings elucidate complex ion insertion and storage dynamics around a layered polyanionic compound, which undergoes intercalation and conversion reactions in a sequential manner. This study of NiPS3 material exemplifies the Li-ion storage mechanism in transition metal phosphorus sulfide materials and provides insights into the challenges associated with achieving reliable, high-energy phosphorus trisulfide systems.

18.
Arch Dis Child Educ Pract Ed ; 107(4): 276-278, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-33328191

RESUMEN

Case presentationA 14-year-old boy, with autism spectrum disorder, presented with a 1-day history of colicky abdominal pain, non-bilious vomiting, anorexia and loose normal-coloured stool. Two days previously, he had a poorly reheated takeaway chicken.On examination, body mass index (BMI) was >99th centile. He had inconsistent epigastric, periumbilical and umbilical tenderness, and guarding, with normal bowel sounds. Observations were within normal limits, but his pain was poorly responsive to paracetamol, ibuprofen, hyoscine butylbromide, codeine and morphine.Investigations are in table 1. On day 3, his temperature increased to 38.5° and a CT scan was performed, which showed concerning features (figure 1).


Asunto(s)
Analgesia , Apendicitis , Trastorno del Espectro Autista , Abdomen , Dolor Abdominal/tratamiento farmacológico , Dolor Abdominal/etiología , Analgesia/efectos adversos , Apendicitis/complicaciones , Apendicitis/diagnóstico , Trastorno del Espectro Autista/complicaciones , Diarrea , Humanos , Masculino
19.
Sci Rep ; 11(1): 19515, 2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34593833

RESUMEN

Recent advances in detectors for imaging and spectroscopy have afforded in situ, rapid acquisition of hyperspectral data. While electron energy loss spectroscopy (EELS) data acquisition speeds with electron counting are regularly reaching 400 frames per second with near-zero read noise, signal to noise ratio (SNR) remains a challenge owing to fundamental counting statistics. In order to advance understanding of transient materials phenomena during rapid acquisition EELS, trustworthy analysis of noisy spectra must be demonstrated. In this study, we applied machine learning techniques to denoise high frame rate spectra, benchmarking with slower frame rate "ground truths". The results provide a foundation for reliable use of low SNR data acquired in rapid, in-situ spectroscopy experiments. Such a tool-set is a first step toward both automation in microscopy as well as use of these methods to interrogate otherwise poorly understood transformations.

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