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This study reports on a set of experiments designed to clarify the impact of the rotational transform on confinement quality at the TJ-II stellarator. For this purpose, the net plasma current is controlled using external coils, resulting in the modification of the rotational transform profile. Significant and systematic variations of the edge electron density gradients (up to $50\,\%{-}60\,\%$) and the plasma energy content ($20\,\%{-}30\,\%$) are achieved. The explanation of this behaviour relies on the placement of low-order rational surfaces in relation to the edge gradient region, which affect local turbulence fluctuation levels, facilitating the formation of zonal flows and concomitant transport barriers. This hypothesis is confirmed experimentally on the basis of a broad array of diagnostic measurements. Calculations based on a resistive magnetohydrodynamic turbulence model provide qualitative support for this hypothesis, clarifying the impact on confinement of specific rational surfaces and highlighting the complex nature of magnetically confined fusion plasmas.
Multicenter clinical trials are essential for evaluating interventions but often face significant challenges in study design, site coordination, participant recruitment, and regulatory compliance. To address these issues, the National Institutes of Health’s National Center for Advancing Translational Sciences established the Trial Innovation Network (TIN). The TIN offers a scientific consultation process, providing access to clinical trial and disease experts who provide input and recommendations throughout the trial’s duration, at no cost to investigators. This approach aims to improve trial design, accelerate implementation, foster interdisciplinary teamwork, and spur innovations that enhance multicenter trial quality and efficiency. The TIN leverages resources of the Clinical and Translational Science Awards (CTSA) program, complementing local capabilities at the investigator’s institution. The Initial Consultation process focuses on the study’s scientific premise, design, site development, recruitment and retention strategies, funding feasibility, and other support areas. As of 6/1/2024, the TIN has provided 431 Initial Consultations to increase efficiency and accelerate trial implementation by delivering customized support and tailored recommendations. Across a range of clinical trials, the TIN has developed standardized, streamlined, and adaptable processes. We describe these processes, provide operational metrics, and include a set of lessons learned for consideration by other trial support and innovation networks.
Radiotherapy aims to provide either curative treatment or palliation, with radiation transmission through shielding blocks ideally not exceeding 5% of the incident dose.
Aim:
This study assessed the attenuation efficacy of Cerrobend shielding blocks, determining the thickness required for achieving 95% attenuation and evaluating the adequacy of currently used blocks.
Methods:
An experimental study was conducted using a 1·25 MeV cobalt-60 teletherapy machine. Radiation intensities transmitted through Cerrobend blocks of varying thicknesses (1–5 cm) were measured with a calibrated ionization chamber and electrometer. Measurements were performed with a fixed field size of 10 cm × 10 cm at a 100-cm source-to-chamber distance, minimizing scatter. Baseline and transmitted intensities were recorded, with each measurement repeated five times for precision.
Results:
The percentage transmission, linear attenuation coefficients and thickness required for 5% transmission were calculated using regression analysis. Radiation intensity decreased exponentially with increasing Cerrobend block thickness, from 15·01 nC (0 cm) to 0·939 nC (5 cm thickness). Regression analysis showed a strong negative linear relationship (y = −0·5386x + 2·6705; R2 = 0·992). The thickness required for maximum transmission of 5% was determined to be 6 cm, while the routinely used 5 cm blocks at the study site allowed 8% transmission, exceeding the recommended threshold. Minimal environmental variations ensured measurement consistency.
Conclusion:
The study demonstrated that 6 cm Cerrobend blocks were necessary to achieve the recommended 95% attenuation, whereas the 5 cm blocks in use resulted in suboptimal shielding. This highlights the need to revise shielding practices to improve radiation protection and patient safety in resource-constrained radiotherapy settings.
Cortical excitability has been proposed as a novel neurophysiological marker of neurodegeneration in Alzheimer’s dementia (AD). However, the link between cortical excitability and structural changes in AD is not well understood.
Objective:
To assess the relationship between cortical excitability and motor cortex thickness in AD.
Methods:
In 62 participants with AD (38 females, mean ± SD age = 74.6 ± 8.0) and 47 healthy control (HC) individuals (26 females, mean ± SD age = 71.0 ± 7.9), transcranial magnetic stimulation resting motor threshold (rMT) was determined, and T1-weighted MRI scans were obtained. Skull-to-cortex distance was obtained manually for each participant using MNI coordinates of the motor cortex (x = −40, y = −20, z = 52).
Results:
The mean skull-to-cortex distances did not differ significantly between participants with AD (22.9 ± 4.3 mm) and HC (21.7 ± 4.3 mm). Participants with AD had lower motor cortex thickness than healthy individuals (t(92) = −4.4, p = <0.001) and lower rMT (i.e., higher excitability) than HC (t(107) = −2.0, p = 0.045). In the combined sample, rMT was correlated positively with motor cortex thickness (r = 0.2, df = 92, p = 0.036); however, this association did not remain significant after controlling for age, sex and diagnosis.
Conclusions:
Patients with AD have decreased cortical thickness in the motor cortex and higher motor cortex excitability. This suggests that cortical excitability may be a marker of neurodegeneration in AD.
Radiotherapy is a critical component of head and neck cancer (HNC) management that requires reliable patient immobilization. Using thermoplastic masks helps to ensure reproducible patient positioning during radiotherapy, thus reducing the risk of a geographical miss. However, the use of these masks can also induce anxiety and distress, which can negatively impact treatment adherence and quality of life outcomes.
Methods:
The research was a quantitative cross-sectional study that determined the prevalence and severity of thermoplastic mask-induced anxiety and assessed the scope of coping mechanisms used by HNC patients. Data were collected using a structured questionnaire from recruited participants and analysed with the Statistical Package for Social Sciences software, version 26·0. Relevant clinical and treatment-related data were retrieved from patients’ hospital-based medical records. Descriptive and inferential statistical analyses such as chi-square tests and likelihood ratios were conducted, with p-values < 0·05 considered statistically significant.
Results:
In all, there were 145 HNC patients with a male to female ratio of 1·9:1 and a median age of 52·8 years (IQR 20·7), ranging from 18 to 82 years. There was a high prevalence of thermoplastic mask-induced anxiety both during mask moulding (93·8%) and radiation therapy sessions (94·5%). Most participants (95·2%) adopted coping mechanisms including distraction (58%) and visualization techniques (46%).
Conclusions:
Even though there was a high level of awareness and utilization of coping mechanisms, the high prevalence of thermoplastic mask-induced anxiety highlights a critical aspect of HNC patient care that may be overlooked in resource-limited settings.
Wilms tumor (WT) is the most common renal malignancy in children, with a peak incidence between the ages of 3 and 4 years. This study aimed to evaluate the clinicopathological features, treatment characteristics and survival outcomes of patients managed for WT at the study site.
Methods:
This was a quantitative cross-sectional study involving 137 pediatric patients diagnosed with and managed for WT between 2012 and 2021. Total population sampling was used for participant selection. Data were analyzed using SPSS software, with Kaplan-Meier and Cox regression analysis used to estimate survival rates and examine prognostic factors. P-values < 0·05 were considered statistically significant.
Results:
The 2- and 5-year overall survival (OS) rates were 75% and 70%, respectively, while the disease-free survival (DFS) rates at 2- and 5-years were both 79%. Pathological staging significantly impacted OS and DFS (p = 0·000), while age, gender, weight and risk stratification did not show statistically significant differences. The left kidney was the most common primary site (51%), with an even male to female gender ratio of 1:1. Metastases were most common in the chest (n = 19, 13·8%) and lungs (n = 13, 9·5%).
Conclusions:
Pathological stage was the most significant prognostic factor for both OS and DFS, emphasizing the importance of early detection and timely intervention. While the 2- and 5-year OS and DFS rates represent an improvement over previous studies in Ghana, they remain suboptimal compared to outcomes in high-income countries. A holistic, coordinated institutional treatment regimen has enhanced patient compliance, survival outcomes and follow-up care.
Heterogeneous symptoms in major depression contribute to unsuccessful antidepressant treatment, termed treatment-resistant depression (TRD). Psychometric network modeling conceptualizes depression as interplay of symptoms with potential benefits for treatment; however, a knowledge gap exists regarding networks in TRD.
Methods
Symptoms from 1,385 depressed patients, assessed by the Montgomery-Åsberg-depression rating scale (MADRS) as part of the “TRD-III” cohort of the multinational research consortium “Group for the Studies of Resistant Depression,” were used for Gaussian graphical network modeling. Networks were estimated for two timepoints, pretreatment and posttreatment, after the establishment of outcomes response, non-response, and TRD. Applying the network-comparison test, edge weights, and symptom centrality was assessed by bootstrapping. Applying the network-comparison test, outcome groups were compared cross-sectionally and longitudinally regarding the networks’ global strength, invariance, and centrality.
Results
Pretreatment networks did not differ in global strength, but outcome groups showed distinct symptom connections. For both response and TRD, global strength was reduced posttreatment, leading to significant differences between each pair of networks posttreatment. Sadness, lassitude, inability-to-feel, and pessimistic thoughts ranked most centrally in unfavorable outcomes, while reduced-appetite and suicidal thoughts were more densely connected in response. Connections between central symptoms increased in strength following unsuccessful treatment, particularly regarding links involving pessimistic thoughts in TRD.
Conclusion
Treatment reduced global network strength across outcome groups. However, distinct symptom networks were found in patients showing response to treatment, non-response, and TRD. More easily targetable symptoms such as reduced-appetite were central to networks in patients with response, while pessimistic thoughts may be a key symptom upholding disease burden in TRD.
The stars of the Milky Way carry the chemical history of our Galaxy in their atmospheres as they journey through its vast expanse. Like barcodes, we can extract the chemical fingerprints of stars from high-resolution spectroscopy. The fourth data release (DR4) of the Galactic Archaeology with HERMES (GALAH) Survey, based on a decade of observations, provides the chemical abundances of up to 32 elements for 917 588 stars that also have exquisite astrometric data from the Gaia satellite. For the first time, these elements include life-essential nitrogen to complement carbon, and oxygen as well as more measurements of rare-earth elements critical to modern-life electronics, offering unparalleled insights into the chemical composition of the Milky Way. For this release, we use neural networks to simultaneously fit stellar parameters and abundances across the whole wavelength range, leveraging synthetic grids computed with Spectroscopy Made Easy. These grids account for atomic line formation in non-local thermodynamic equilibrium for 14 elements. In a two-iteration process, we first fit stellar labels to all 1 085 520 spectra, then co-add repeated observations and refine these labels using astrometric data from Gaia and 2MASS photometry, improving the accuracy and precision of stellar parameters and abundances. Our validation thoroughly assesses the reliability of spectroscopic measurements and highlights key caveats. GALAH DR4 represents yet another milestone in Galactic archaeology, combining detailed chemical compositions from multiple nucleosynthetic channels with kinematic information and age estimates. The resulting dataset, covering nearly a million stars, opens new avenues for understanding not only the chemical and dynamical history of the Milky Way but also the broader questions of the origin of elements and the evolution of planets, stars, and galaxies.
The risk of losing access to crucial means-tested programs — like Medicaid, Supplemental Security Income (SSI), the Supplemental Nutrition Assistance Program (SNAP), and Temporary Assistance for Needy Families (TANF) — poses a barrier to the enrollment of low-income Americans in clinical trials. This burden likely disproportionately affects members of racial and ethnic minority groups, people with disabilities, elderly individuals, and rural populations, and may frustrate efforts to reflect the US population in clinical trial enrollment. To help achieve representative clinical trials for myriad conditions, Congress should pass legislation excluding payments to clinical trial participants from gross income and expand the clinical trial compensation exclusions for means-tested programs established in the Ensuring Access to Clinical Trials Act of 2015.
Antibiotics overuse leads to bacterial resistance. The biomarker procalcitonin rises with bacterial pneumonias and remains normal in viral respiratory tract infections. Its use can distinguish between these etiologies and thus guide antibiotics use. We aimed to quantify the effect of procalcitonin use on clinical decision-making.
Design:
A retrospective study, spanning a year at a tertiary care center, where 348 patients hospitalized with aspiration pneumonia and 824 with non-aspiration pneumonia were evaluated with regards to procalcitonin use, the length of stay (LOS) and antibiotics prescribing practices. Descriptive statistics and univariate analyses were applied to the ensemble data. Subsets of cases were manually reviewed and analyzed with descriptive statistics. P < 0.05 indicated statistical significance.
Results:
21% of both the aspiration and non-aspiration pneumonia cases had procalcitonin checked. In the ensemble analyses, a check of procalcitonin was more likely to happen in prolonged hospitalizations with aspiration pneumonia. The LOS was statistically the same regardless of procalcitonin results (elevated or normal) for both the aspiration and non-aspiration pneumonia cohorts. The overall use of antibiotics was not affected by the procalcitonin results. After excluding two extreme outliers, the per-person antibiotics cost was not affected by the procalcitonin results. Detailed chart reviews of 33 cases revealed that for the vast majority, the procalcitonin results were not used by clinicians to guide the duration of antibiotics use.
Conclusions:
Despite its promise as a biomarker for antibiotics stewardship, procalcitonin results appeared to not be utilized by clinicians as a decision-making tool in the management of pneumonia.
Cervical cancer remains a significant public health concern in sub-Saharan Africa, with treatment modalities such as chemoradiotherapy impacting patients’ quality of life (QoL). This study assessed the QoL of cervical cancer patients undergoing definitive chemoradiotherapy.
Methods:
This cross-sectional study was conducted at the National Radiotherapy, Oncology and Nuclear Medicine Centre, Korle-Bu Teaching Hospital, Accra, between February and May 2023. A total of 120 adult female cervical cancer patients, treated with definitive chemoradiotherapy, were purposively recruited. Data were collected using the FACT-Cx questionnaire, which assessed physical, social, emotional and functional well-being as well as additional concerns. Statistical analysis included descriptive and inferential methods with Spearman Rho used to examine correlations.
Results:
The mean age of participants was 53·5 years (SD 15·6), with most (77%) employed and half (50%) married. QoL scores were highest in social well-being (mean = 17·3/24·0) and emotional well-being (mean = 16·8/24·0), but lower in physical (mean = 15·4/28·0) and functional well-being (mean = 12·3/24·0). Most participants (66·7%) reported a good QoL, while 6·7% reported poor QoL. Key challenges included fatigue, pain and dissatisfaction with sex life, although participants received strong emotional support from their families. Correlations between age and QoL domains were statistically insignificant (p > 0·05).
Conclusions:
The findings suggest that despite the physical and functional challenges faced during chemoradiotherapy, most participants reported good overall QoL, largely attributed to strong family and social support. Future studies should incorporate longitudinal designs with baseline data collection to better understand treatment-related changes in QoL.
Edited by
Dharti Patel, Mount Sinai West and Morningside Hospitals, New York,Sang J. Kim, Hospital for Special Surgery, New York,Himani V. Bhatt, Mount Sinai West and Morningside Hospitals, New York,Alopi M. Patel, Rutgers Robert Wood Johnson Medical School, New Jersey
This chapter gives a brief overview of different endocrine hormones relevant to the practice of anesthesiology. This chapter also discusses metabolism and biochemistry relevant to the practice of anesthesiology.
Recent debates over the relationship between omniscience and free will have generated a number of views (e.g. Ockhamism). Though fascinating in their own right, what interests us in this paper is not so much the views themselves, but the way that intuitions have figured prominently in justifying these views. Proponents of the various views assume that their intuitions are the most pre-philosophically natural (or closely aligned with common sense) and therefore best situated to serve as justifications for their views. These implicit claims, however, are not a priori justified; they require empirical investigation. To take a modest step forward in exploring pre-philosophical intuitions about the relationship between omniscience and free will we conducted a series of experiments which presented participants with three cases (two are prominent in the free will and philosophy of religion literatures: Newcomb’s Paradox (Nozick 1969) and Plantinga’s ‘ant colony’ (1986)). Experiment 1 sampled US participants from varied religious backgrounds. Experiment 2 used English-language vignettes and sampled non-Christian persons from India. Experiment 3 used Korean-language translations, and sampled two groups of South Koreans, Christians and non-Christians. Analysis of the data revealed that pre-philosophical intuitions about omniscience and free will are describable as compatibilist.
Fear of cardiac arrest among parents of infants with heart disease can cause stress and anxiety. Literature is scarce on the effects of cardiopulmonary resuscitation training (CPRt) on anxiety and stress of parents. We analysed the impact of CPRt on anxiety, stress, and comfort levels on parents of infants with heart disease.
Methods:
Cardiopulmonary resuscitation (CPR) and choking relief manoeuvre (CRM) comfort level, Parental State-Trait Anxiety Inventory (STAI), and Parenting Stress Index (PSI) scores were prospectively collected pre-, immediately post-, and 3 months post-CPRt.
Results:
There were 97 participants: 80% (n = 78) mothers/grandmothers and 20% (n = 19) fathers. The mean (SD) age of participants was 28.7 (5.6) years old. There was a significant decrease in STAI across the three time points collected; STAI decreased by 12% from baseline to immediately post-CPRt and 19% from baseline to 3 months post-CPRt (p < .0001). There were no significant changes in PSI across the time points. Baseline to immediately post-teaching, we found that CPRt significantly increased comfort performing CPR, CRM, and comfort in knowing what to do (p=< .001, p=< .001, p=< .001, respectively). Comfort levels persisted elevated when comparing pre- to 3 months post-CPRt (p=< .001, p= .002, p= .001, respectively), maintaining at least a 177% average increase up to 3 months post-CPRt for all aspects.
Conclusion:
CPRt can aid in improving anxiety and comfort levels of parents of infants with heart disease around hospital discharge. Parental preparedness and reassurance to know what to do in emergency situations can be enhanced by a simple intervention such as CPRt.
We present a 1000 km transect of phase-sensitive radar measurements of ice thickness, basal reflection strength, basal melting and ice-column deformation across the Ross Ice Shelf (RIS). Measurements were gathered at varying intervals in austral summer between 2015 and 2020, connecting the grounding line with the distant ice shelf front. We identified changing basal reflection strengths revealing a variety of basal conditions influenced by ice flow and by ice–ocean interaction at the ice base. Reflection strength is lower across the central RIS, while strong reflections in the near-front and near-grounding line regions correspond with higher basal melt rates, up to 0.47 ± 0.02 m a−1 in the north. Melting from atmospherically warmed surface water extends 150–170 km south of the RIS front. Melt rates up to 0.29 ± 0.03 m a−1 and 0.15 ± 0.03 m a−1 are observed near the grounding lines of the Whillans and Kamb Ice Stream, respectively. Although troublesome to compare directly, our surface-based observations generally agree with the basal melt pattern provided by satellite-based methods but provide a distinctly smoother pattern. Our work delivers a precise measurement of basal melt rates across the RIS, a rare insight that also provides an early 21st-century baseline.
This study sought to assess undergraduate students’ knowledge and attitudes surrounding perceived self-efficacy and threats in various common emergencies in communities of higher education.
Methods
Self-reported perceptions of knowledge and skills, as well as attitudes and beliefs regarding education and training, obligation to respond, safety, psychological readiness, efficacy, personal preparedness, and willingness to respond were investigated through 3 representative scenarios via a web-based survey.
Results
Among 970 respondents, approximately 60% reported their university had adequately prepared them for various emergencies while 84% reported the university should provide such training. Respondents with high self-efficacy were significantly more likely than those with low self-efficacy to be willing to respond in whatever capacity needed across all scenarios.
Conclusions
There is a gap between perceived student preparedness for emergencies and training received. Students with high self-efficacy were the most likely to be willing to respond, which may be useful for future training initiatives.
Research participants” feedback about their participation experiences offers critical insights for improving programs. A shared Empowering the Participant Voice (EPV) infrastructure enabled a multiorganization collaborative to collect, analyze, and act on participants’ feedback using validated participant-centered measures.
Methods:
A consortium of academic research organizations with Clinical and Translational Science Awards (CTSA) programs administered the Research Participant Perception Survey (RPPS) to active or recent research participants. Local response data also aggregated into a Consortium database, facilitating analysis of feedback overall and for subgroups.
Results:
From February 2022 to June 2024, participating organizations sent surveys to 28,096 participants and received 5045 responses (18%). Respondents were 60% female, 80% White, 13% Black, 2% Asian, and 6% Latino/x. Most respondents (85–95%) felt respected and listened to by study staff; 68% gave their overall experience the top rating. Only 60% felt fully prepared by the consent process. Consent, feeling valued, language assistance, age, study demands, and other factors were significantly associated with overall experience ratings. 63% of participants said that receiving a summary of the study results would be very important to joining a future study. Intersite scores differed significantly for some measures; initiatives piloted in response to local findings raised experience scores.
Conclusion:
RPPS results from 5045 participants from seven CTSAs provide a valuable evidence base for evaluating participants’ research experiences and using participant feedback to improve research programs. Analyses revealed opportunities for improving research practices. Sites piloting local change initiatives based on RPPS findings demonstrated measurable positive impact.
Mexico’s consular diplomacy and protection are unique. Mexico has a diaspora of close to 40 million people; approximately 9 percent live in the United States and 12 million of them were born in Mexico. Also, more than 50 percent of Mexicans have a relative living abroad, and over 20 percent of Mexican families receive remittances. Therefore, due to the relevance of its diaspora and its close connections with Mexico, consular diplomacy and protection are high priorities within Mexican foreign policy. This chapter analyzes the current scenario of the Mexican diaspora, as well as the Mexican consular and diplomatic work at a global level and its concentration in the United States; it also explains the economic, social, and military activities carried out by the Mexican state through its diplomatic representations. Its main findings are that Mexico’s policy for protecting its nationals abroad is multifaceted and goes well beyond traditional consular protection, entering the realm of bilateral and multilateral political relations, as well as public diplomacy. The main motivation of consular diplomacy and protection is one of support and, to a lesser degree, one of co-optation, since it seeks to include the Mexican population in the United States as part of a Mexican transnational nation.
Simulating plasma physics on quantum computers is difficult because most problems of interest are nonlinear, but quantum computers are not naturally suitable for nonlinear operations. In weakly nonlinear regimes, plasma problems can be modelled as wave–wave interactions. In this paper, we develop a quantization approach to convert nonlinear wave–wave interaction problems to Hamiltonian simulation problems. We demonstrate our approach using two qubits on a superconducting device. Unlike a photonic device, a superconducting device does not naturally have the desired interactions in its native Hamiltonian. Nevertheless, Hamiltonian simulations can still be performed by decomposing required unitary operations into native gates. To improve experimental results, we employ a range of error-mitigation techniques. Apart from readout error mitigation, we use randomized compilation to transform undiagnosed coherent errors into well-behaved stochastic Pauli channels. Moreover, to compensate for stochastic noise, we rescale exponentially decaying probability amplitudes using rates measured from cycle benchmarking. We carefully consider how different choices of product-formula algorithms affect the overall error and show how a trade-off can be made to best utilize limited quantum resources. This study provides an example of how plasma problems may be solved on near-term quantum computing platforms.
Petrographical and geochemical data from the Togo structural unit (TSU), also referred to as the Atacora structural unit, are presented together with the existing dataset; geochemical and age data from the sedimentary and metasedimentary rocks from the passive margin sequences of the Dahomeyide belt in Ghana to infer their provenance and depositional setting and expand the discussion on the Rodina–Gondwana supercontinent assembly during the Pan-African orogeny. The metasedimentary rocks of the TSU are quartzites and phyllites. The framework grains of the quartzites consisting dominantly of quartz and small amounts of feldspar grains and relict lithic fragments classify them as quartz arenite, subarkose and sublitharenite. Generally, the studied rocks show similar rare-earth element and multi-element patterns, which imply derivation from similar sources. Elemental ratios, including (La/Lu)N, Th/Sc and La/Sc, suggest sediments sourced from intermediate to felsic rocks. Provenance and depositional setting indicators of the TSU suggest deposition in a passive margin setting, with the West African and Amazonian cratons’ granitoids and granitic gneisses as possible provenance, akin to siliciclastic rocks of the Buem structural unit and the Voltaian Supergroup of the Volta Basin. The deformational history of the TSU is similar to those of the Buem structural unit and the eastern margin of the Voltaian Supergroup, indicating the effect of the Pan-African orogeny on the passive margin of the Dahomeyide belt. We, therefore, propose the formation and evolution of a Neoproterozoic passive margin unit, which was tectonically deformed during the Rodinia–Gondwana supercontinent cycle.