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1.
Nature ; 629(8011): 323-328, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38720039

RESUMO

The emergence of quasiparticles in quantum many-body systems underlies the rich phenomenology in many strongly interacting materials. In the context of doped Mott insulators, magnetic polarons are quasiparticles that usually arise from an interplay between the kinetic energy of doped charge carriers and superexchange spin interactions1-8. However, in kinetically frustrated lattices, itinerant spin polarons-bound states of a dopant and a spin flip-have been theoretically predicted even in the absence of superexchange coupling9-14. Despite their important role in the theory of kinetic magnetism, a microscopic observation of these polarons is lacking. Here we directly image itinerant spin polarons in a triangular-lattice Hubbard system realized with ultracold atoms, revealing enhanced antiferromagnetic correlations in the local environment of a hole dopant. In contrast, around a charge dopant, we find ferromagnetic correlations, a manifestation of the elusive Nagaoka effect15,16. We study the evolution of these correlations with interactions and doping, and use higher-order correlation functions to further elucidate the relative contributions of superexchange and kinetic mechanisms. The robustness of itinerant spin polarons at high temperature paves the way for exploring potential mechanisms for hole pairing and superconductivity in frustrated systems10,11. Furthermore, our work provides microscopic insights into related phenomena in triangular-lattice moiré materials17-20.

2.
Cureus ; 16(1): e52922, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38406124

RESUMO

Background This study aims to investigate the prevalence of thumb and wrist pain among smartphone users in the general population of Saudi Arabia, examining the potential links between the duration and frequency of smartphone usage, specific smartphone activities, and the occurrence of discomfort in the thumb and wrist. Methodology This descriptive cross-sectional study was conducted at Jazan University, Saudi Arabia, between July 2022 and June 2023. The questionnaire developed following an extensive literature review, covered demographic information, smartphone usage patterns, assessment of thumb or wrist pain, and evaluation of the impact of this discomfort. Descriptive statistical methods were employed, and relationships between thumb or wrist pain and demographic variables were analyzed using chi-square and Wilcoxon rank-sum tests. Results In total, 811 participants were included in this study. Approximately 322 (39.7%) study participants reported wrist or thumb pain. Notably, female sex (P = 0.001) and prolonged daily smartphone usage exceeding five hours (P = 0.045) were linked to thumb or wrist pain. Additionally, emailing on smartphones was linked to thumb or wrist pain (P = 0.04). Concerning smartphone ergonomics, the majority of respondents reported holding their phones with one hand (215, 66.77%), in a downward position (290, 90.06%), and with their wrists bent downward (136, 42.24%). Conclusions Our study highlights a relatively high prevalence of wrist and thumb pain among smartphone users in the general Saudi Arabian population. Furthermore, we identified a connection between prolonged smartphone use and wrist and thumb pain, with a more pronounced prevalence observed among females.

3.
Cureus ; 15(4): e37110, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37153321

RESUMO

Introduction Risk factors for developing gallstones are related to disturbances in either cholesterol or bilirubin metabolism in the biliary tract. The risk of forming gallstones can be associated with chronic illnesses, dietary habits, reduced gallbladder motility, and medications. Our study aims to explore the causal relationship between multiple risk factors, including nutritional habits (cheese intake, salad intake, processed meat intake, coffee drinking), smoking behavior, overall obesity measured by body mass index (BMI), lipid biomarkers, total bilirubin and maternal diabetes mellitus (DM) and the development of gallstone disease in two different populations of European ancestry (United Kingdom Biobank (UKB) and FinnGen). Materials and methods Using publicly available genome-wide association studies (GWAS) data, we performed a two-sample Mendelian randomization (MR) to examine the association between risk factors and gallstone development. Exposures used in this study included age of smoking initiation, smoking intensity, coffee intake, cheese intake, salad intake, processed meat intake, BMI, and lipid biomarkers (cholesterol, low-density lipoproteins (LDL), triglycerides (TG), and high-density lipoproteins (HDL)). Current analyses were based on 93 single nucleotide polymorphisms (SNPs) for smoking initiation, four SNPs for smoking intensity, 65 SNPs for cheese intake, three SNPs for coffee intake, 22 SNPs for salad intake, 23 SNPs for processed meat intake, 79 SNPs for BMI, 26 SNPs for maternal DM, 89 SNPs for total bilirubin, 46 SNPs for cholesterol, 41 SNPs for LDL, 55 SNPs for TG, and 89 SNPs for HDL. The outcome in this study is gallstones/cholelithiasis. To evaluate the causal relationships between these risk factors and gallstones, two-sample MR methods were used. TwoSampleMR package in R software version 4.0.5 (R Foundation for Statistical Computing, Vienna, Austria) was used to obtain MR analyses and sensitivity analyses. Results  In the UKB, genetic predispositions to smoking initiation, BMI, and total bilirubin were significantly associated with an increased risk of gallstones. The odds of gallstones would increase per 1-SD increase of genetically estimated smoking initiation (OR: 1.004, P=0.008), BMI (OR: 1.02, P<0.001), and total bilirubin (OR: 1.0001, P=0.025). Conversely, genetic predispositions to cheese intake, coffee intake, cholesterol, LDL, and TG were statistically significantly associated with a decreased risk of gallstones (OR=0.99, P=0.014; OR=0.97, P=0.009; OR=0.99, P=0.006; OR=0.99, P=0.01; and OR=0.99, P<0.001, respectively). In FinnGen, genetic predispositions to BMI and total bilirubin were significantly associated with an increased risk of gallstones. The odds of gallstones would increase per 1-SD increase of genetically estimated BMI (OR: 1.7, P<0.001) and total bilirubin (OR: 1.02, P=0.002). Conversely, genetic predispositions to cheese intake, coffee intake, cholesterol, LDL, and TG were statistically significantly associated with a decreased risk of gallstones (OR=0.23, P=0.006; OR=0.42, P=0.041; OR=0.77, P=0.034; OR=0.88, P=0.008; and OR=0.70, P=0.005, respectively). Conclusion  Genetically estimated BMI and total bilirubin levels were associated with increased risk of gallstones among the two populations while genetically estimated cheese intake, coffee intake, and cholesterol, LDL, and TG levels factors were consistently associated with reduced risk of gallstones among the two populations.

4.
Eur Spine J ; 32(4): 1099-1105, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36843147

RESUMO

PURPOSE: Foot drop can uncommonly be a painless presenting symptom of degenerative spinal disorders. This systematic review aimed to summarise the literature on the management and outcomes of patients with a painless foot drop. METHODS: We performed a systematic review of PubMed, EMBASE and Medline according to PRISMA guidelines. All studies published after 1980 in English referring to adult patients with a painless foot drop were included. Exclusion criteria included opinion based reports, review articles and articles in which foot drop was not caused by degenerative pathology of the thoracolumbar spine. RESULTS: Of 62 included patients, 30 (48.4%) were male with an average age of 48.7 years (range 27-84). The mean duration of symptoms was 69.0 days (1-700). 98.8% were managed operatively. 46 (74.2%) patients had symptomatic improvement, with 41 (66.1%) having a post-intervention MRC power grading of 3 or above. Patients with a pre-procedure MRC 0 had a higher median increase in MRC post-procedure than those with MRC > 0. Of two studies comparing painful and painless symptoms, painless foot drop patients were less likely to recover to MRC equal to or over 3 than those with painful symptoms OR 0.31 (95% CI 0.04-2.65). CONCLUSION: This systematic review and meta-analysis demonstrates a role for surgery in facilitating the neurological recovery of patients with a painless foot drop. Large randomised controlled studies are required to characterise the role of operative intervention in these patients and compare outcomes between patients with painless and painful foot drop.


Assuntos
Doenças da Coluna Vertebral , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Doenças da Coluna Vertebral/cirurgia
5.
BMC Oral Health ; 23(1): 100, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36788563

RESUMO

BACKGROUND: This study aimed to three-dimensionally compare the maxillary growth among the spheno-occipital synchondrosis (SOS) maturation stages in both genders. METHODS: This is a cross-sectional study of a retrospective type in which cone-beam computed tomography (CBCT) images of 500 patients aged 6 to 25 years (226 males and 274 females) were analyzed. The SOS was evaluated using the four-stage scoring system; completely open, partially fused, semi-fused, or completely fused. The SOS scoring and three-dimensional cephalometric measurements were analyzed by Invivo 6.0.3 software. Descriptive and analytical statistics were performed and a P-value < 0.05 was considered statistically significant. RESULTS: There was a statistically significant difference in maxillary measurements among SOS maturation stages in both genders (P < 0.05). The mean differences in the maxillary growth among the SOS maturation stages between SOS stages 2 and 3 were higher than those between stages 1and 2 and stages 3 and 4 for maxillary length and height in both genders. However, the mean difference in the maxillary width was higher between SOS stages 1 and 2 than those stages 2 and 3 and stages 3 and 4. On other hand, there may be lesser maxillary growth between SOS stages 3 and 4 for maxillary width, length (in males), and height. The growth curves showed high active growth of the maxilla as the SOS was still fusing (especially stage 2 and 3) than those of the fused (stage 4). Moreover, the acceleration of growth occurred earlier in females than males regarding chronological age but not for SOS maturation stages. CONCLUSIONS: The SOS maturation stages are valid and reliable maxillary skeletal maturation indicators for three-dimensional maxillary growth in both genders.


Assuntos
Maxila , Osso Occipital , Osso Esfenoide , Feminino , Humanos , Masculino , Tomografia Computadorizada de Feixe Cônico/métodos , Estudos Transversais , Maxila/diagnóstico por imagem , Osso Occipital/diagnóstico por imagem , Estudos Retrospectivos , Osso Esfenoide/diagnóstico por imagem
6.
Nature ; 614(7946): 64-69, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36725998

RESUMO

Synthetic quantum systems with interacting constituents play an important role in quantum information processing and in explaining fundamental phenomena in many-body physics. Following impressive advances in cooling and trapping techniques, ensembles of ultracold polar molecules have emerged as a promising platform that combines several advantageous properties1-11. These include a large set of internal states with long coherence times12-17 and long-range, anisotropic interactions. These features could enable the exploration of intriguing phases of correlated quantum matter, such as topological superfluids18, quantum spin liquids19, fractional Chern insulators20 and quantum magnets21,22. Probing correlations in these phases is crucial to understanding their properties, necessitating the development of new experimental techniques. Here we use quantum gas microscopy23 to measure the site-resolved dynamics of quantum correlations of polar 23Na87Rb molecules confined in a two-dimensional optical lattice. By using two rotational states of the molecules, we realize a spin-1/2 system with dipolar interactions between particles, producing a quantum spin-exchange model21,22,24,25. We study the evolution of correlations during the thermalization process of an out-of-equilibrium spin system for both spatially isotropic and anisotropic interactions. Furthermore, we examine the correlation dynamics of a spin-anisotropic Heisenberg model engineered from the native spin-exchange model by using periodic microwave pulses26-28. These experiments push the frontier of probing and controlling interacting systems of ultracold molecules, with prospects for exploring new regimes of quantum matter and characterizing entangled states that are useful for quantum computation29,30 and metrology31.

7.
Int Dent J ; 73(3): 410-416, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36153169

RESUMO

OBJECTIVE: The present study aimed to estimate the location of the incisive canal (IC) concerning the upper central incisor roots (U1) in order to explore the amount of incisor retraction as per the envelope of discrepancy amongst Chinese patients with different vertical facial growth patterns. METHODS: This is a cross-sectional study that used a total of 207 pretreatment cone-beam computed tomography (CBCT) scans of adults with a skeletal class I relationship. Sixty-nine cases were included in each of the normodivergent, hypodivergent, and hyperdivergent facial groups. The IC volume was measured using Mimics 21 software. The IC width and IC-U1 proximity were measured using in vivo 6 software. Linear measurements were conducted at 3 vertical levels. RESULTS: The IC has shown a larger volume in the hyperdivergent group and male patients. Overall, the IC has recorded linear width greater than the inter-root distance of U1 in 59.1%, 66%, and 68.8% amongst the normodivergent, hypodivergent, and hyperdivergent facial groups, respectively, and in 58.3% of males and 70.8% of females. The overall sagittal distances between the U1 and IC were 4.00 ± 0.82 mm, 4.60 ± 0.83 mm, and 3.60 ± 0.80 mm amongst the normodivergent, hypodivergent, and hyperdivergent facial groups, respectively. CONCLUSIONS: The maximum sagittal distances between U1 and IC were 4.8 mm, 5.4 mm, and 4.4 mm amongst the normodivergent, hypodivergent, and hyperdivergent facial groups, respectively. Thereby, our findings have revised the retraction aspect of the envelope of discrepancy as per the different vertical facial growth patterns, which could serve a reference for the clinical practice involved considerable incisors movement, especially among Chinese patients.


Assuntos
Incisivo , Maxila , Adulto , Feminino , Humanos , Masculino , Incisivo/diagnóstico por imagem , Maxila/diagnóstico por imagem , Estudos Transversais , Tomografia Computadorizada de Feixe Cônico/métodos , Assistência Odontológica
8.
BMC Oral Health ; 22(1): 654, 2022 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-36585639

RESUMO

BACKGROUND: This study aimed to compare spheno-occipital synchondrosis (SOS) maturation stages with a three-dimensional assessment of mandibular growth. METHODS: This is a cross-sectional study of a retrospective type, in which cone-beam computed tomography (CBCT) images of 500 patients aged 6 to 25 years (226 males and 274 females) were analyzed. The SOS was evaluated using the four-stage scoring system; completely open, partially fused, semi-fused, or completely fused. The SOS scoring and three-dimensional cephalometric measurements were analyzed by Invivo 6.0.3 software. Descriptive and analytical statistics were performed, and a P-value < 0.05 was considered statistically significant. RESULTS: There was a statistically significant difference in mandibular measurements among SOS maturation stages in both sexes (P < 0.05). The skeletal growth increments of mandibular variables across the SOS stages had higher mean differences between SOS stages 2 and 3 than those between stages 1 and 2 and stages 3 and 4 in both sexes. The mandibular growth curves increased with chronological age (earlier in females) and SOS maturation stages (mostly in stages 1, 2, and 3 than stage 4). CONCLUSIONS: The SOS maturation stages are valid and reliable mandibular skeletal indicators as evaluated with three-dimensional cephalometric mandibular measurements. The findings of growth increments and constructed growth curves of mandibular growth might be helpful in diagnosis and treatment planning.


Assuntos
Osso Occipital , Osso Esfenoide , Masculino , Feminino , Humanos , Osso Occipital/diagnóstico por imagem , Osso Esfenoide/diagnóstico por imagem , Estudos Retrospectivos , Estudos Transversais , Mandíbula/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos
9.
Phys Rev Lett ; 129(12): 123201, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36179199

RESUMO

We prepare high-filling two-component arrays of tens of fermionic ^{6}Li atoms in optical tweezers, with the atoms in the ground motional state of each tweezer. Using a stroboscopic technique, we configure the arrays in various two-dimensional geometries with negligible Floquet heating. A full spin- and density-resolved readout of individual sites allows us to postselect near-zero entropy initial states for fermionic quantum simulation. We prepare a correlated state in a two-by-two tunnel-coupled Hubbard plaquette, demonstrating all the building blocks for realizing a programmable fermionic quantum simulator.

10.
J Contemp Dent Pract ; 23(1): 8-13, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35656651

RESUMO

AIM: This study sought to assess the fusion of spheno-occipital synchondrosis (SOS) in Chinese population using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: This is a cross-sectional study in which data were randomly collected based on the pre-existing institutional records. Following selection criteria, the CBCT images of 500 patients aged 6-25 years (226 males and 274 females) were analyzed. Three-dimensional virtual models were oriented at a standardized position, then adjusted to the median sagittal plane (MSP) view. A four-stage scoring system was used; completely open, partially fused, semi-fused, or completely fused. The student's t-test, one-way ANOVA, Pearson correlation, and linear regression analysis were used and the significant level was set at ≤0.05. RESULTS: The mean age of closure of stages 1, 2, 3, and 4 were 7.44, 9.62, 12.94, and 19.03 years in females, and 8.79, 11.13, 14.82, and 20.18 years in males, respectively. There was significantly strong positive correlation between spheno-occipital fusion and age (female: r = 0.853, male: r = 0.879; p <0.001), with 1.47 ± 0.33 years earlier fusion in females. All inter- and intra-stages mean ages were statistically significant in both genders. The transition age model demonstrated a mean age (in years) between stages 1-2 (10.1), stages 2-3 (12.79), and stage 3-4 (17.93) for males, and stages 1-2 (8.96), stages 2-3 (11.45), and stage 3-4 (16.69) for females. CONCLUSIONS: The present findings of SOS stages of fusion in both genders could guide age estimation and assessment of normal skeletal growth patterns and active skeletal growth period in the Chinese population. CLINICAL SIGNIFICANCE: There is still controversy about the time to closure of the SOS because of population and assessment technique variations. This study could be used as a reference for the specific examined population during planning for dentofacial orthopedic and/or orthognathic surgery and dental implant prosthesis for both genders. Moreover, these finding may be useful for medical purposes.


Assuntos
Osso Occipital , Tomografia Computadorizada de Feixe Cônico Espiral , Adolescente , Adulto , Determinação da Idade pelo Esqueleto/métodos , Criança , China , Estudos Transversais , Feminino , Humanos , Masculino , Osso Occipital/diagnóstico por imagem , Osso Esfenoide/diagnóstico por imagem , Adulto Jovem
11.
Phys Rev Lett ; 128(22): 223202, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35714242

RESUMO

We use lithium-6 atoms in an optical tweezer array to realize an eight-site Fermi-Hubbard chain near half filling. We achieve single site detection by combining the tweezer array with a quantum gas microscope. By reducing disorder in the energy offsets to less than the tunneling energy, we observe Mott insulators with strong antiferromagnetic correlations. The measured spin correlations allow us to put an upper bound on the entropy of 0.26(4)k_{B} per atom, comparable to the lowest entropies achieved with optical lattices. Additionally, we establish the flexibility of the tweezer platform by initializing atoms on one tweezer and observing tunneling dynamics across the array for uniform and staggered 1D geometries.

12.
JPRAS Open ; 32: 211-213, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33907705

RESUMO

The pandemic caused by SARS-CoV-2 virus, also known as COVID-19, has generated shockwaves in medical and surgical practice. It has necessitated re-deployment of staff and resources to cater for the unpredictable increase in footfall and demand on healthcare systems. This study aimed to investigate how the restructuring of our service altered the triage and management of non-melanoma skin cancer (NMSC) during the pandemic's first wave rise and peak. We retrospectively analysed all patients who underwent a skin excision under local anaesthetic which revealed the presence of a basal cell carcinoma (BCC) or squamous cell carcinoma (SCC) on histopathological analysis between 1st February 2020 - 31st May 2020 compared with the same period in 2019. There was a 158% increase in patients with excision of lesions confirmed on histopathological analysis as a NMSC during the COVID-19 period (168 vs. 65). In 2020, more excisions were performed by consultants (42.9% v 21.5%, p = 0.002) with a lower proportion of excisions with a close margin (27.7% v 17.8%, p = 0.096) and an involved margin (3.1% v 1.8%, p = 0.62). Five of these patients had their further management altered due to service constraints at this time The resource constraints secondary to the pandemic have yielded beneficial service adaptations with the incorporation of a more efficient model for the NMSC service. The sustainability of this model and its impact on training will require further examination when non-urgent and benign elective workload is slowly reinstated and plastic surgery trainees return to their original posts.

13.
Ann R Coll Surg Engl ; 104(8): 594-599, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34941462

RESUMO

INTRODUCTION: The COVID-19 pandemic has changed the presentation of many medical and surgical conditions, including major trauma. We aimed to assess how lockdown changed the presentation, severity and management of major trauma patients at our level 1 trauma centre in England. METHODS: Data were collected retrospectively from the Trauma Audit and Research Network's database between 23 March and 28 April 2020 and compared with the same period in 2019. Collected data included patient demographics, and the mechanism, severity and management of injuries. RESULTS: We experienced a 56.4% reduction in major trauma admissions during the lockdown period when compared with 2019. In 2020, more patients arrived in haemodynamic shock (25.3% vs 12.2%, p=0.02); however, Glasgow Coma Scale and Injury Severity Score were unchanged. A higher proportion of incidents occurred at home (37.2% vs 53.5%, p=0.018), with no difference in trauma secondary to substance abuse or assault. During lockdown, patients had a significantly shorter hospital (17 vs 10 days, p=0.029) and critical care stay (2 vs 1 day, p=0.033). A higher proportion of major trauma patients were assessed by specialty trainees in the emergency department in 2020 (12.8% vs 53.1%, p=0.0001) with a lower proportion assessed by a consultant (69.8% vs 46.7%, p=0.001). CONCLUSIONS: The COVID-19 pandemic and lockdown drastically changed human behaviour, as reflected in the change in presentation of major trauma. Changes in the management of these patients reflect adaptive measures to manage the pressures generated by the worldwide pandemic.


Assuntos
COVID-19 , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Inglaterra/epidemiologia , Humanos , Pandemias , Estudos Retrospectivos , Centros de Traumatologia
14.
Injury ; 52(8): 2322-2326, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34083023

RESUMO

AIMS: Fractures of the pelvis and acetabulum are often the consequence of high energy trauma in young individuals or fragility fractures in osteoporotic bone. They can be life-threatening or life changing injuries. No published data exists comparing body mass index (BMI) and mortality for this patient group. The aim of this study was to identify if low BMI (<18.5) was a predictor of morbidity and mortality for patients with these injuries. PATIENTS AND METHODS: Of the 1033 patients with pelvic or acetabular fractures referred to a single level 1 major trauma centre (MTC) over a 4.5-year period (August 2015 - January 2020); we retrospectively analysed data for all admitted patients. Data was collected on demographics, injury pattern, operative intervention and complications. Comparison was made between patients that were underweight (BMI<18.5) and patients that were not. Both in-hospital and post discharge complications were recorded including pulmonary embolus (PE), deep venous thrombosis (DVT), ileus, infection, loss of reduction and mortality at 6 months. RESULTS: 569 patients admitted to the MTC with a pelvic or acetabular fracture were included in our analysis. Underweight patients had a statistically significant increase in mortality both in-hospital (p = 0.019) and at 6 months post injury (p = 0.039) when compared to other BMI groups. No statistical significance was found between these BMI groups comparing morbidity: DVT (p = 0.712), PE (p = 0.736) nor ileus (p = 0.149). Covariate analysis showed that a low BMI was associated with triple the in-hospital mortality after correction for age and energy of injury (adjusted OR 3.028, 95% CI 1.059-8.659). CONCLUSION: This is the first published study that demonstrates a statistically significant increase in mortality in patients with pelvic or acetabular fractures who are underweight. Surgeons should carefully consider appropriate peri-operative optimisation for these patients. Further investigation into the effects of low BMI and response to trauma is required.


Assuntos
Fraturas Ósseas , Fraturas do Quadril , Ossos Pélvicos , Acetábulo , Assistência ao Convalescente , Índice de Massa Corporal , Fraturas Ósseas/complicações , Fraturas Ósseas/cirurgia , Humanos , Alta do Paciente , Pelve , Estudos Retrospectivos , Fatores de Risco
15.
Phys Rev X ; 11(2)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36451802

RESUMO

We induce strong nonlocal interactions in a 2D Fermi gas in an optical lattice using Rydberg dressing. The system is approximately described by a t - V model on a square lattice where the fermions experience isotropic nearest-neighbor interactions and are free to hop only along one direction. We measure the interactions using many-body Ramsey interferometry and study the lifetime of the gas in the presence of tunneling, finding that tunneling does not reduce the lifetime. To probe the interplay of nonlocal interactions with tunneling, we investigate the short-time-relaxation dynamics of charge-density waves in the gas. We find that strong nearest-neighbor interactions slow down the relaxation. Our work opens the door for quantum simulations of systems with strong nonlocal interactions such as extended Fermi-Hubbard models.

16.
J Clin Orthop Trauma ; 12(1): 200-207, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33223749

RESUMO

Purpose; The COVID-19 pandemic has necessitated profound adaptations in the delivery of healthcare to manage a rise in critically unwell patients. In an attempt to slow the spread of the virus nationwide lockdown restrictions were introduced. This review aims to scope the literature on the impact of the pandemic and subsequent lockdown on the presentation and management of trauma globally. Methods; A scoping review was conducted in accordance with PRISMA-ScR guidelines. A systematic search was carried out on the Medline, EMBASE and Cochrane databases to identify papers investigating presentation and management of trauma during the COVID-19 pandemic. All studies based on patients admitted with orthopaedic trauma during the COVID-19 pandemic were included. Exclusion criteria were opinion-based reports, reviews, studies that did not provide quantitative data and papers not in English. Results; 665 studies were screened, with 57 meeting the eligibility criteria. Studies reported on the footfall of trauma in the UK, Europe, Asia, USA, Australia and New Zealand. A total of 29,591 patients during the pandemic were considered. Mean age was 43.7 years (range <1-103); 54.8% were male. Reported reductions in trauma footfall ranged from 20.3% to 84.6%, with a higher proportion of trauma occurring secondary to interpersonal violence, deliberate self-harm and falls from a height. A decrease was seen in road traffic collisions, sports injuries and trauma occurring outdoors. There was no significant change in the proportion of patients managed operatively, and the number of trauma patients reported to be COVID-19 positive was low. Conclusion; Whilst the worldwide COVID-19 pandemic has caused a reduction in the number of trauma patients; the services managing trauma have continued to function despite infrastructural, personnel and pathway changes in health systems. The substantial effect of the COVID-19 pandemic on elective orthopaedics is well described, however the contents of this review evidence minimal change in the delivery of effective trauma care despite resource constraints during this global COVID-19 pandemic.

17.
BMC Anesthesiol ; 19(1): 208, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711438

RESUMO

BACKGROUND: Spinal anesthesia using the midline approach might be technically difficult in geriatric population. We hypothesized that pre-procedural ultrasound (US)-guided paramedian technique and pre-procedural US-guided midline technique would result in a different spinal anesthesia success rate at first attempt when compared with the conventional landmark-guided midline technique in elderly patients. METHODS: In this prospective, randomized, controlled study, one hundred-eighty consenting patients scheduled for elective surgery were randomized into the conventional surface landmark-guided midline technique (group LM), the pre-procedural US-guided paramedian technique (group UP), or the pre-procedural US-guided midline technique (group UM) with 60 patients in each group. All spinal anesthesia were performed by a novice resident. RESULTS: The successful dural puncture rate on first attempt (primary outcome) was higher in groups LM and UM (77 and 73% respectively) than in group UP (42%; P < 0.001). The median number of attempts was lower in groups LM and UM (1 [1] and 1 [1-1.75] respectively) than in group UP (2 [1, 2]; P < 0.001). The median number of passes was lower in groups LM and UM (2 [0.25-3] and 2 [0-4]; respectively) than in group UP (4 [2-7.75]; P < 0.001). The time taken to perform the spinal anesthesia was not different between groups LM and UM (87.24 ± 79.51 s and 116.32 ± 98.12 s, respectively) but shorter than in group UP (154.58 ± 91.51 s; P < 0.001). CONCLUSIONS: A pre-procedural US scan did not improve the ease of midline and paramedian spinal anesthesia as compared to the conventional landmark midline technique when performed by junior residents in elderly population. TRIAL REGISTRATION: Retrospectively registered at Clinicaltrials.gov, registration number NCT02658058, date of registration: January 18, 2016.


Assuntos
Raquianestesia/métodos , Internato e Residência , Palpação/métodos , Ultrassonografia de Intervenção/métodos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
18.
Avicenna J Med ; 9(2): 75-77, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143700

RESUMO

Kyphoplasty is a minimally invasive procedure intended to stabilize the fractured bone and restore bone height. It involves percutaneous introduction of an inflatable bone tamp into a fractured vertebral body, followed by injection of bone cement into the ballooned pocket. Anesthetic options typically considered for this procedure include intravenous sedation or general anesthesia. These patients are often elderly, frail, in significant pain, and may poorly tolerate sedation or general anesthesia in the prone position. Spinal anesthesia has been suggested as an alternative method. However, it has major limitations. We would like to report a case of a 79-year-old patient with multiple comorbidities, who presented for kyphoplasty, where epidural anesthesia was conducted and successfully provided adequate analgesia as well as optimal surgical conditions.

19.
Science ; 363(6425): 379-382, 2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30523078

RESUMO

Strong interactions in many-body quantum systems complicate the interpretation of charge transport in such materials. To shed light on this problem, we study transport in a clean quantum system: ultracold lithium-6 in a two-dimensional optical lattice, a testing ground for strong interaction physics in the Fermi-Hubbard model. We determine the diffusion constant by measuring the relaxation of an imposed density modulation and modeling its decay hydrodynamically. The diffusion constant is converted to a resistivity by using the Nernst-Einstein relation. That resistivity exhibits a linear temperature dependence and shows no evidence of saturation, two characteristic signatures of a bad metal. The techniques we developed in this study may be applied to measurements of other transport quantities, including the optical conductivity and thermopower.

20.
New Microbes New Infect ; 26: 89-91, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30310680

RESUMO

The clinical spectrum of human disease caused by Trueperella bernardiae is poorly described, partly as a result of historical difficulties with microbial identification. With the introduction of powerful new technologies, such as matrix-assisted desorption ionization-time of flight mass spectrometry, into routine microbiology laboratories, new insights into diseases caused by such organisms are being made. Here we report a case of septic thrombophlebitis with bacteraemia caused by this organism, together with a retrospective description of laboratory isolation of this organism over a period of 6 years in a hospital in London, UK.

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