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Ever since Shor's quantum algorithm for factoring integers was discovered three decades ago, showing that quantum algorithms could solve a problem relevant to everyday cryptography, researchers have been working to expand the list of real-world problems to which quantum computing can be applied. This book surveys the fruits of this effort, covering proposed quantum algorithms for concrete problems in many application areas, including quantum chemistry, optimization, finance, and machine learning. The book clearly states the problem being solved and the full computational complexity of the quantum algorithm, making sure to account for the contribution from all the underlying primitive ingredients. Separately, the book also provides a detailed, independent summary of the most common algorithmic primitives. The book has a modular, encyclopedic format to facilitate navigation of the material, and to provide a quick reference for designers of quantum algorithms and quantum computing researchers. This title is also available as open access on Cambridge Core.
In order to improve the performance of $k - \omega $ SST model in turbomachinery, previous studies have used the machine-learning (ML) technique to obtain turbulence models (for example, the ML-RANS EQ model). However, these models do not lead to satisfactory results in complex flows in turbomachinery. In this study, we use non-equilibrium training dataset to obtain a new turbulence model (i.e., the ML-RANS TR-NE-EQ model). Calculations in various cases of turbine cascade flows show that ML-RANS TR-NE-EQ model performs obviously better than ML-RANS EQ model as well as $k - \omega $ SST model.
Increased rehabilitation intensity, the number of minutes of therapy per day, is associated with improved outcomes. However, it is unclear whether males and females receive the same inpatient stroke rehabilitation intensity. A sub-analysis of a retrospective population-based cohort study of adults (5877 females, 6893 males) with stroke discharged to inpatient rehabilitation between 2017 and 2021 was conducted. The mean rehabilitation intensity was 75.86 min/day for males and 73.33 min/day for females (p < .0001). Males <80 years of age were more likely to receive higher rehabilitation intensity than females. Future research should explore what factors account for this sex difference.
Folate metabolism is involved in the development and progression of various cancers. We investigated the association of single nucleotide polymorphisms (SNP) in folate-metabolising genes and their interactions with serum folate concentrations with overall survival (OS) and liver cancer-specific survival (LCSS) of newly diagnosed hepatocellular carcinoma (HCC) patients. We detected the genotypes of six SNP in three genes related to folate metabolism: methylenetetrahydrofolate reductase (MTHFR), 5-methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR) and 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR). Cox proportional hazard models were used to calculate multivariable-adjusted hazard ratios (HR) and 95 % CI. This analysis included 970 HCC patients with genotypes of six SNP, and 864 of them had serum folate measurements. During a median follow-up of 722 d, 393 deaths occurred, with 360 attributed to HCC. In the fully-adjusted models, the MTRR rs1801394 polymorphism was significantly associated with OS in additive (per G allele: HR = 0·84, 95 % CI: 0·71, 0·99), co-dominant (AG v. AA: HR = 0·77; 95 % CI: 0·62, 0·96) and dominant (AG + GG v. AA: HR = 0·78; 95 % CI: 0·63, 0·96) models. Carrying increasing numbers of protective alleles was linked to better LCSS (HR10–12 v. 2–6 = 0·70; 95 % CI: 0·49, 1·00) and OS (HR10–12 v. 2–6 = 0·67; 95 % CI: 0·47, 0·95). Furthermore, we observed significant interactions on both multiplicative and additive scales between serum folate levels and MTRR rs1801394 polymorphism. Carrying the variant G allele of the MTRR rs1801394 is associated with better HCC prognosis and may enhance the favourable association between higher serum folate levels and improved survival among HCC patients.
Stroke outcomes research requires risk-adjustment for stroke severity, but this measure is often unavailable. The Passive Surveillance Stroke SeVerity (PaSSV) score is an administrative data-based stroke severity measure that was developed in Ontario, Canada. We assessed the geographical and temporal external validity of PaSSV in British Columbia (BC), Nova Scotia (NS) and Ontario, Canada.
Methods:
We used linked administrative data in each province to identify adult patients with ischemic stroke or intracerebral hemorrhage between 2014-2019 and calculated their PaSSV score. We used Cox proportional hazards models to evaluate the association between the PaSSV score and the hazard of death over 30 days and the cause-specific hazard of admission to long-term care over 365 days. We assessed the models’ discriminative values using Uno’s c-statistic, comparing models with versus without PaSSV.
Results:
We included 86,142 patients (n = 18,387 in BC, n = 65,082 in Ontario, n = 2,673 in NS). The mean and median PaSSV were similar across provinces. A higher PaSSV score, representing lower stroke severity, was associated with a lower hazard of death (hazard ratio and 95% confidence intervals 0.70 [0.68, 0.71] in BC, 0.69 [0.68, 0.69] in Ontario, 0.72 [0.68, 0.75] in NS) and admission to long-term care (0.77 [0.76, 0.79] in BC, 0.84 [0.83, 0.85] in Ontario, 0.86 [0.79, 0.93] in NS). Including PaSSV in the multivariable models increased the c-statistics compared to models without this variable.
Conclusion:
PaSSV has geographical and temporal validity, making it useful for risk-adjustment in stroke outcomes research, including in multi-jurisdiction analyses.
The target backsheath field acceleration mechanism is one of the main mechanisms of laser-driven proton acceleration (LDPA) and strongly depends on the comprehensive performance of the ultrashort ultra-intense lasers used as the driving sources. The successful use of the SG-II Peta-watt (SG-II PW) laser facility for LDPA and its applications in radiographic diagnoses have been manifested by the good performance of the SG-II PW facility. Recently, the SG-II PW laser facility has undergone extensive maintenance and a comprehensive technical upgrade in terms of the seed source, laser contrast and terminal focus. LDPA experiments were performed using the maintained SG-II PW laser beam, and the highest cutoff energy of the proton beam was obviously increased. Accordingly, a double-film target structure was used, and the maximum cutoff energy of the proton beam was up to 70 MeV. These results demonstrate that the comprehensive performance of the SG-II PW laser facility was improved significantly.
Background: Lower socioeconomic status is associated with worse outcomes after stroke. We evaluated the differences in acute revascularization treatments in patients with acute ischemic stroke (AIS) who were materially deprived compared to those who were not. Methods: In a population-based cohort study, we used linked administrative data to identify community-dwelling adults hospitalized for AIS between 2017-2022 in Ontario, Canada. The main exposure was neighborhood-level material deprivation quintiles. Multivariable logistic regression was used to obtain the adjusted odds ratio (aOR) of receiving revascularization treatments (thrombolysis or thrombectomy) for patients in each deprivation quintile compared to the least deprived quintile. Results: We identified 57,709 patients (median age 74 years; 45.9% female). Compared to patients in the least deprived quintile, those with higher deprivation were younger and more likely to have hypertension and diabetes, but less likely to have atrial fibrillation. Compared to patients in the least deprived quintile, fewer patients in the very deprived quintile (17.9% vs 19.6%, aOR 0.88, 95%CI [0.82,0.95]) and in the most deprived quintile (16.6% vs 19.6%, 0.77 [0.71,0.83]) received revascularization treatments. Conclusions: Our results suggest disparities in the use of acute ischemic stroke revascularization treatments by socioeconomic status despite access to universal health care.
Profitability, yield, and fertilizer use are compared across three different potassium (K) fertilizer rate recommendation ideologies. Existing agronomic, “build and maintain” rate recommendations (KE) are compared to profit-maximizing rates with and without taking long-run soil-test K (STK) implications into account. Regardless of starting STK, K use equilibrated over the course of 3 years irrespective of ideology. Since taking long-run STK into account did not alter ending STK and only led to a miniscule yield effect, we encourage producers to use annual profit-maximizing K rates that were 3–11% lower than KE rates and generated more profit with minimal yield loss.
We derive from first principles analytic relations for the second- and third-order moments of $\boldsymbol{\mathsf{m}}$, the spatial gradient of fluid velocity $\boldsymbol{u}$, $\boldsymbol{\mathsf{m}} = \nabla \boldsymbol{u}$, in compressible turbulence, which generalize known relations in incompressible flows. These relations, although derived for homogeneous flows, hold approximately for a mixing layer. We also discuss how to apply these relations to determine all the second- and third-order moments of the velocity gradient experimentally for isotropic compressible turbulence.
While the negative consequences of insomnia are well-documented, a strengths-based understanding of how sleep can increase health promotion is still emerging and much-needed. Correlational evidence has connected sleep and insomnia to resilience; however, this relationship has not yet been experimentally tested. This study examined resilience as a mediator of treatment outcomes in a randomized clinical trial with insomnia patients.
Methods
Participants were randomized to either digital cognitive behavioral therapy for insomnia (dCBT-I; n = 358) or sleep education control (n = 300), and assessed at pre-treatment, post-treatment, and 1-year follow-up. A structural equation modeling framework was utilized to test resilience as a mediator of insomnia and depression. Risk for insomnia and depression was also tested in the model, operationalized as a latent factor with sleep reactivity, stress, and rumination as indicators (aligned with the 3-P model). Sensitivity analyses tested the impact of change in resilience on the insomnia relapse and incident depression at 1-year follow-up.
Results
dCBT-I resulted in greater improvements in resilience compared to the sleep education control. Furthermore, improved resilience following dCBT-I lowered latent risk, which was further associated with reduced insomnia and depression at 1-year follow-up. Sensitivity analyses indicated that each point improvement in resilience following treatment reduced the odds of insomnia relapse and incident depression 1 year later by 76% and 65%, respectively.
Conclusions
Improved resilience is likely a contributing mechanism to treatment gains following insomnia therapy, which may then reduce longer-term risk for insomnia relapse and depression.
Introduction. While many individuals quit smoking during pregnancy, most relapse within one year postpartum. Research into methods to decrease smoking relapse postpartum has been hampered by difficulties with recruitment. Method. We conducted individual interviews with pregnant women (N = 22) who were interested in quitting smoking while pregnant about their attitudes regarding smoking and quitting during pregnancy, clinical trial participation, and smoking cessation medication use. Results. Participants were aware of the risks of smoking while pregnant. Many wanted to quit smoking before delivery. Few used empirically supported treatments to quit. While research was viewed positively, interest in taking on new commitments postpartum and taking a medication to prevent relapse was low. Medication concerns were evident among most participants, especially among those planning to breastfeed. Further, several women noted medication was unnecessary, as they did not believe they would relapse postpartum. Financial incentives, childcare, and fewer and/or remote visits were identified as facilitators to participating in research. However, these factors did not outweigh women’s concerns about medication use and time commitments. Conclusions. Women are aware that quitting smoking during pregnancy and remaining smoke-free postpartum are important. However, beliefs that personal relapse risk is low and that medications are dangerous reduced enthusiasm for taking medication for postpartum relapse prevention. Future medication trials should educate women about the high likelihood of relapse, prepare to answer detailed questions about risks of cessation medications, and connect with participants’ clinicians. For new mothers, studies conducted remotely with few scheduled appointments would reduce barriers to participation.
This study aimed to research risk factors of hearing loss among neonates in the neonatal intensive care unit.
Method
Hearing screening tests were performed on 572 neonates in the neonatal intensive care unit. Those who failed screening tests were referred for diagnostic tests.
Results
The pass rates for automated auditory brainstem response, distortion product otoacoustic emission and acoustic impedance tests at first hearing screening were 69.93 per cent, 70.02 per cent and 92.92 per cent for 1144 ears. Failure in the first screening correlated with preterm birth, very low birth weight, revised advanced maternal age, neonatal hyperbilirubinaemia and Activity, Pulse, Grimace, Appearance, Respiration score less than 8. Thirty cases failed in diagnostic hearing tests for brainstem auditory evoked potentials, 28 failed in otoacoustic emissions and 33 failed in acoustic impedance, which correlated with preterm birth, very low birth weight, twins, advanced maternal age and revised advanced maternal age.
Conclusion
Abnormalities in the hearing levels of most neonates who needed hearing retests were completely or partially reversible. Preterm birth, very low birth weight, twins and advanced maternal age are potential risk factors for hearing impairment.
To explore the factors associated with the operative duration for paediatric tracheobronchial foreign body removal by rigid bronchoscopy, and to analyse the learning curve for mastery of the rigid bronchoscopy skill.
Methods
A retrospective study was performed of paediatric cases of tracheobronchial foreign body removal by rigid bronchoscopy in our department from January 2007 to July 2019. Multivariate Cox regression analysis was used to analyse the factors associated with the operative duration. In addition, the learning curves for two doctors were evaluated by curve-fitting regression analysis.
Results
A total of 410 paediatric cases of tracheobronchial foreign body removal by rigid bronchoscopy were evaluated. The operative duration was significantly influenced by the skill of the doctor. The learning curves for both doctor A and doctor B demonstrated two typical phases: an initially rapidly changing learning phase followed by a steady consolidation phase.
Conclusion
The operative duration for paediatric tracheobronchial foreign body removal by rigid bronchoscopy was associated with the skill of the doctor. In order to fully master the rigid bronchoscopy technique, doctors should perform a minimum number of procedures to pass the learning phase and reach the consolidation phase.
A classical result for the simple symmetric random walk with 2n steps is that the number of steps above the origin, the time of the last visit to the origin, and the time of the maximum height all have exactly the same distribution and converge when scaled to the arcsine law. Motivated by applications in genomics, we study the distributions of these statistics for the non-Markovian random walk generated from the ascents and descents of a uniform random permutation and a Mallows(q) permutation and show that they have the same asymptotic distributions as for the simple random walk. We also give an unexpected conjecture, along with numerical evidence and a partial proof in special cases, for the result that the number of steps above the origin by step 2n for the uniform permutation generated walk has exactly the same discrete arcsine distribution as for the simple random walk, even though the other statistics for these walks have very different laws. We also give explicit error bounds to the limit theorems using Stein’s method for the arcsine distribution, as well as functional central limit theorems and a strong embedding of the Mallows(q) permutation which is of independent interest.
This study aimed to investigate the association of nasal nitric oxide and olfactory function.
Method
A cross-sectional study was performed in 117 adults, including 91 patients with chronic rhinosinusitis and 26 healthy controls. Scores on the 22-item Sino-Nasal Outcomes Test, Lund-Mackay scale and Lund-Kennedy scale were recorded to assess severity of disease. All participants were screened for common inhaled and food allergens. Nasal nitric oxide and fractional exhaled nitric oxide testing, acoustic rhinometry and anterior rhinomanometry testing were performed to measure nasal function. The validated Sniffin’ Sticks test battery was used to assess olfactory function.
Results
Higher nasal nitric oxide was an independent protective factor for odour discrimination and odour threshold in participants with chronic rhinosinusitis after adjusting for age, gender, drinking, smoking, 22-item Sino-Nasal Outcomes Test, Lund-Mackay score, Lund-Kennedy score, immunoglobulin E and the second minimal cross-sectional area by acoustic rhinometry. Nasal nitric oxide also showed high discrimination in predicting impaired odour discrimination. In addition, nasal nitric oxide was lower in older participants, those with higher Lund-Mackay or Lund-Kennedy scores and higher with elevated total serum immunoglobulin E concentrations above a threshold of 0.35 kU/l.
Conclusion
Higher nasal nitric oxide is associated with better odour discrimination in chronic rhinosinusitis and is modulated by age, degree of allergy and severity of chronic rhinosinusitis.
This study aims for a greater understanding of how older adults (age 65 and older) in Jackson County, Florida, are prepared for and cope with the effects of a natural disaster.
Methods:
A multidisciplinary, international research team developed a survey examining: (1) resources available to individuals aged 65+ in rural communities for preparing for a disaster; (2) challenges they face when experiencing a disaster; and (3) their physical, social, emotional, and financial needs when it strikes. The survey was administered with older adults (65+) in Jackson County, Florida, following Hurricane Michael in 2018. The descriptive, multivariate logistic, and linear regression analyses were performed to examine the relationship between respondents’ demographic information and needs, concerns, and consequences of disaster.
Results:
Results indicated (n = 139) rural community-dwelling older adults rely on social support, community organizations, and trusted disaster relief agencies to prepare for and recover from disaster-related events.
Conclusions:
Such findings can be used to inform the development of new interventions, programs, policies, practices, and tools for emergency management and social service agencies to improve disaster preparedness and resiliency among older populations in rural communities.
Population reductions in Na intake could prevent hypertension, and current guidelines recommend that clinicians advise patients to reduce intake. This study aimed to estimate the prevalence of taking action and receiving advice from a health professional to reduce Na intake in ten US jurisdictions, including the first-ever data in New York state and Guam.
Design:
Weighted prevalence and 95 % CI overall and by location, demographic group, health status and receipt of provider advice using self-reported data from the 2017 Behavioral Risk Factor Surveillance System optional Na module.
Setting:
Seven states, the District of Columbia, Puerto Rico and Guam.
Participants:
Adults aged ≥ 18 years.
Results:
Overall, 53·6 % (95 % CI 52·7, 54·5) of adults reported taking action to reduce Na intake, including 54·8 % (95 % CI 52·8, 56·7) in New York and 61·2 % (95 % CI 57·6, 64·7) in Guam. Prevalence varied by demographic and health characteristic and was higher among adults who reported having hypertension (72·5 %; 95 % CI 71·2, 73·7) v. those who did not report having hypertension (43·9 %; 95 % CI 42·7, 45·0). Among those who reported receiving Na reduction advice from a health professional, 82·6 % (95 % CI 81·3, 83·9) reported action v. 44·4 % (95 % CI 43·4, 45·5) among those who did not receive advice. However, only 24·0 % (95 % CI 23·3, 24·7) of adults reported receiving advice from a health professional to reduce Na intake.
Conclusions:
The majority of adults report taking action to reduce Na intake. Results highlight an opportunity to increase Na reduction advice from health professionals during clinical visits to better align with existing guidelines.
Lifestyle interventions are an important and viable approach for preventing cognitive deficits. However, the results of studies on alcohol, coffee and tea consumption in relation to cognitive decline have been divergent, likely due to confounds from dose–response effects. This meta-analysis aimed to find the dose–response relationship between alcohol, coffee or tea consumption and cognitive deficits.
Methods
Prospective cohort studies or nested case-control studies in a cohort investigating the risk factors of cognitive deficits were searched in PubMed, Embase, the Cochrane and Web of Science up to 4th June 2020. Two authors searched the databases and extracted the data independently. We also assessed the quality of the studies with the Newcastle-Ottawa scale. Stata 15.0 software was used to perform model estimation and plot the linear or nonlinear dose–response relationship graphs.
Results
The search identified 29 prospective studies from America, Japan, China and some European countries. The dose–response relationships showed that compared to non-drinkers, low consumption (<11 g/day) of alcohol could reduce the risk of cognitive deficits or only dementias, but there was no significant effect of heavier drinking (>11 g/day). Low consumption of coffee reduced the risk of any cognitive deficit (<2.8 cups/day) or dementia (<2.3 cups/day). Green tea consumption was a significant protective factor for cognitive health (relative risk, 0.94; 95% confidence intervals, 0.92–0.97), with one cup of tea per day brings a 6% reduction in risk of cognitive deficits.
Conclusions
Light consumption of alcohol (<11 g/day) and coffee (<2.8 cups/day) was associated with reduced risk of cognitive deficits. Cognitive benefits of green tea consumption increased with the daily consumption.