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Prolonged overall treatment time (OTT) in radiotherapy (RT) for head and neck cancer (HNC), particularly beyond 49 days, has been linked to poorer tumour control and survival, primarily due to accelerated tumour repopulation. Identifying modifiable factors contributing to treatment delays may help improve outcomes. This study aimed to evaluate the association between pre-treatment clinical, nutritional and inflammatory factors and prolonged OTT.
Methods:
We retrospectively analysed patients with non-metastatic HNC treated with definitive or postoperative RT (with or without chemotherapy) between 2020 and 2022. Pre-treatment factors included Eastern Cooperative Oncology Group (ECOG) performance status, tumour stage, treatment modality, body mass index (BMI), weight loss, sarcopenia (via C3 computed tomography imaging), neutrophil-to-lymphocyte ratio (NLR) and absolute lymphocyte count. Logistic regression was used to identify predictors of prolonged OTT (> 49 days).
Results:
Among 465 patients, 287 (61·7%) experienced prolonged OTT. Multivariable analysis identified ECOG status (OR 1·42, p = 0·004), significant weight loss > 5% (OR 1·26, p = 0·036), concurrent chemotherapy (OR 1·96, p = 0·005), NLR (OR 1·03, p = 0·041) and sarcopenia (OR 1·18, p = 0·042) as independent predictors. Patient-related delays accounted for 53·3% of OTT prolongation, while public holidays contributed to 42·5%.
Conclusions:
Several modifiable pre-treatment factors—including poor performance status, pre-treatment weight loss, sarcopenia and systemic inflammation—were independently associated with OTT prolongation. These findings provide evidence to support early, patient-tailored interventions such as prehabilitation and intensive nutritional counselling before and during RT. In addition, system-level strategies, including staffing adjustments and compensatory scheduling during public holidays, may further reduce avoidable treatment delays and enhance care delivery.
Given a fixed small graph H and a larger graph G, an H-factor is a collection of vertex-disjoint subgraphs $H'\subset G$, each isomorphic to H, that cover the vertices of G. If G is the complete graph $K_n$ equipped with independent U(0,1) edge weights, what is the lowest total weight of an H-factor? This problem has previously been considered for $H=K_2$, for example. We show that if H contains a cycle, then the minimum weight is sharply concentrated around some $L_n = \Theta(n^{1-1/d^*})$ (where $d^*$ is the maximum 1-density of any subgraph of H). Some of our results also hold for H-covers, where the copies of H are not required to be vertex-disjoint.
For an arbitrary countable discrete infinite group G, non-singular rank-one actions are introduced. It is shown that the class of non-singular rank-one actions coincides with the class of non-singular $(C,F)$-actions. Given a decreasing sequence of cofinite subgroups in G with $\bigcap _{n=1}^\infty \bigcap _{g\in G}g\Gamma _ng^{-1}=\{1_G\}$, the projective limit of the homogeneous G-spaces $G/\Gamma _n$ as $n\to \infty $ is a G-space. Endowing this G-space with an ergodic non-singular non-atomic measure, we obtain a dynamical system which is called a non-singular odometer. Necessary and sufficient conditions are found for a rank-one non-singular G-action to have a finite factor and a non-singular odometer factor in terms of the underlying $(C,F)$-parameters. Similar conditions are also found for a rank-one non-singular G-action to be isomorphic to an odometer. Minimal Radon uniquely ergodic locally compact Cantor models are constructed for the non-singular rank-one extensions of odometers. Several concrete examples are constructed and several facts are proved that illustrate a sharp difference of the non-singular non-commutative case from the classical finite measure preserving one: odometer actions which are not of rank-one and factors of rank-one systems which are not of rank one; however, each probability preserving odometer is a factor of an infinite measure preserving rank-one system, etc.
There is ongoing debate on the nosological position of bipolar disorder (BD) and borderline personality disorder (BPD). Identifying the unique and shared risks, developmental pathways, and symptoms in emerging BD and BPD could help the field refine aetiological hypotheses and improve the prediction of the onset of these disorders. This study aimed to: (a) systematically synthesise the available evidence from systematic reviews (SRs) and meta-analyses (MAs) concerning environmental, psychosocial, biological, and clinical factors leading to the emergence of BD and BPD; (b) identify the main differences and common features between the two disorders to characterise their complex interplay and, (c) highlight remaining evidence gaps.
Methods
Data sources were; PubMed, PsychINFO, Embase, Cochrane, CINAHL, Medline, ISI Web of Science. Overlap of included SRs/MAs was assessed using the corrected covered area process. The methodological quality of each included SR and MA was assessed using the AMSTAR.
Results
22 SRs and MAs involving 249 prospective studies met eligibility criteria. Results demonstrated that family history of psychopathology, affective instability, attention deficit hyperactivity disorder, anxiety disorders, depression, sleep disturbances, substance abuse, psychotic symptoms, suicidality, childhood adversity and temperament were common predisposing factors across both disorders. There are also distinct factors specific to emerging BD or BPD.
Conclusions
Prospective studies are required to increase our understanding of the development of BD and BPD onset and their complex interplay by concurrently examining multiple measures in BD and BPD at-risk populations.
Increasing evidence suggests psychosis may be more meaningfully viewed in dimensional terms rather than as discrete categorical states and that specific symptom clusters may be identified. If so, particular risk factors and premorbid factors may predict these symptom clusters.
Aims.
(i) To explore, using principal component analysis, whether specific factors for psychotic symptoms can be isolated. (ii) To establish the predictors of the different symptom factors using multiple regression techniques.
Method.
One hundred and eighty-nine inpatients with psychotic illness were recruited and information on family history, premorbid factors and current symptoms obtained from them and their mothers.
Results.
Seven distinct symptom components were identified. Regression analysis failed to identify any developmental predictors of depression or mania. Delusions/hallucinations were predicted by a family history of schizophrenia and by poor school functioning in spite of normal premorbid IQ (F = 6.5; P < 0.001); negative symptoms by early onset of illness, developmental delay and a family history of psychosis (F = 4.1; P = 0.04). Interestingly disorganisation was predicted by the combination of family history of bipolar disorder and low premorbid IQ (F = 4.9; P = 0.003), and paranoia by obstetric complications (OCs) and poor school functioning (F = 4.2; P = 0.01).
Conclusion.
Delusions and hallucinations, negative symptoms and paranoia all appeared to have a developmental origin though they were associated with different childhood problems. On the other hand, neither mania nor depression was associated with childhood dysfunction. Our most striking finding was that disorganisation appeared to arise when a familial predisposition to mania was compounded by low premorbid IQ.
The purpose of the study was to evaluate burden of main caregivers in children with epilepsy and to identify factors associated with caregiver burden.
Method
Main caregivers of pediatric patients with epilepsy were enrolled four general hospitals in several cities of Korea. One hundred and twenty-fou caregivers of patients were included in this cross-sectional study. Sociodemograhic/clinical characteristics of patients and sociodemographic characteristics of caregivers were collected. The caregivers were assessed using the Korean version Zarit burden Interview (ZBI), Center for Epidemiological Studies of Depression Scale (CES-D) and social support/conflict scale. Multiple linear regression methods were used to evaluate factors contributing to burden of caregivers.
Results
Of the 124 participants, 98(81.7%) were the mothers. The mean score on the ZBI and CES-D were 23.66 (± 19.15) and 13.87 (± 12.95) points, respectively. Factors affecting of caregiver burden were the number of antiepileptic drugs (AEDs), which patients are taking, and CES-D score by multiple linear regression analysis.
Conclusions
Higher number of AEDs prescribed and depression of caregivers are main factors contributing to burden of caregivers in children with epilepsy.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Using Mathematica and the Wolfram Language to engage with the the algebra encountered in a precalculus or college algebra setting. Includes solving equations and simplifying expressions.
Cronbach's alpha is often used as a key measure of reliability in questionnaires developed in HCI. However, the state-of-the-art literature on Cronbach's alpha shows that it is itself not a reliable measure. This chapter demonstrates the problems and leads to a more nuanced interpretation of reliability, using both Cronbach's alpha and other more modern alternatives.
Factor analysis is quite regularly seen in HCI to validate questionnaires, particularly those used to measure user experience. This chapter describes and illustrates the process of developing a questionnaire to measure a particular concept, starting from item generation through to factor analysis and interpretation. It introduces bifactor analysis as a more recent development in factor analysis that could help the interpretation of questionnaires made up of multiple factors.
For a division ring $D$, denote by ${{\mathcal{M}}_{D}}$ the $D$-ring obtained as the completion of the direct limit $\underset{\to n}{\mathop \lim }\,{{M}_{{{2}^{n}}}}(D)$ with respect to themetric induced by its unique rank function. We prove that, for any ultramatricial $D$-ring $B$ and any non-discrete extremal pseudo-rank function $N$ on $B$, there is an isomorphism of $D$-rings $\overline{B}\,\cong \,{{\mathcal{M}}_{D}}$, where $\overline{B}$ stands for the completion of $B$ with respect to the pseudo-metric induced by $N$. This generalizes a result of von Neumann. We also show a corresponding uniqueness result for $*$-algebras over fields $\text{F}$ with positive definite involution, where the algebra ${{\mathcal{M}}_{\text{F}}}$ is endowed with its natural involution coming from the $*$-transpose involution on each of the factors ${{M}_{{{2}^{n}}}}\,(F)$.
The objective of this study was to determine the factors associated with selling price of animals at livestock marts around Ireland. Data consisted of four distinct maturity categories: calves (2 to 84 days of age, n = 53 838); weanlings (6 to 12 months of age, n = 19 972); post-weanlings (12 to 36 months of age, n = 93 081) and cows (>30 months to 12 years of age, n = 94 839); sold through livestock marts between 2000 and 2008. Factors associated with animal price were determined within each maturity category separately using mixed models; random effects were mart, date of sale nested within mart, and herd of origin nested within year of sale. Mean selling price was €157, €580, €655 and €592 for calves, weanlings, post-weanlings and cows, respectively. The greatest prices were paid for singleton crossbred male calves, weanlings and post-weanlings from older dams. With the exception of the Aberdeen Angus, beef breeds and their crosses consistently received higher prices than their dairy counterparts across all four maturity categories; increased proportion of Belgian Blue and Charolais was associated with greater prices compared with other beef breeds. When live-weight was included in the multiple regression models the association between price and all factors regressed toward zero but most factors remained associated with price. The highest price was recorded in the spring months for calves, post-weanlings and cows, and in the autumn months for weanlings. Results from this study may be used to help farmers make more informed management decisions, as well as provide information for bio-economic models for evaluating alternative production systems or estimating economic values.
This article sketches a subtheory of human intelligence based on the component construct. Components differ in their levels of generality and in their functions. Metacomponents are higher-order control process used for planning how a problem should be solved, for making decisions regarding alternative courses of action during problem solving, and for monitoring solution processes. Performance components are processes used in the execution of a problem-solving strategy. Acquisition components are processes used in learning new information. Retention components are processes used in retrieving previously stored knowledge. Transfer components are used in generalization, that is, in carrying over knowledge from one task or task context to another. A mechanism for the interaction among components of different kinds and multiple components of the same kind can account for certain interesting aspects of laboratory and everyday problem solving. A brief historical overview of alternative basic units for understanding intelligence is followed by a detailed description of one of these units, the component and by a differentiation among various kinds of components. Examples of each kind of component are given, and the use of each of these components in a problem-solving situation is illustrated. Then, a system of interrelations among the various kinds of components is described. Finally, the functions of components in human intelligence are assessed by considering how the proposed subtheory can account for various empirical phenomena in the literature on human intelligence.
We study ensembles of similar systemsunder load of environmental factors. The phenomenon of adaptationhas similar properties for systems of different nature. Typically,when the load increases above some threshold, then the adaptingsystems become more different (variance increases), but thecorrelation increases too. If the stress continues to increasethen the second threshold appears: the correlation achievesmaximal value, and start to decrease, but the variance continue toincrease. In many applications this second threshold is a signalof approaching of fatal outcome. This effect is supported by many experiments and observation ofgroups of humans, mice, trees, grassy plants, and on financialtime series. A general approach to explanation of the effectthrough dynamics of adaptation is developed. H. Selye introduced“adaptation energy" for explanation of adaptation phenomena. Weformalize this approach in factors – resource models anddevelop hierarchy of models of adaptation. Different organizationof interaction between factors (Liebig's versus synergisticsystems) lead to different adaptation dynamics. This gives anexplanation to qualitatively different dynamics of correlationunder different types of load and to some deviation from thetypical reaction to stress. In addition to the “quasistatic" optimization factor – resourcemodels, dynamical models of adaptation are developed, and asimple model (three variables) for adaptation to one factor loadis formulated explicitly.
We investigate the role of projections in norming a $C^*$-algebra by a type II1 subfactor. Applications are given for factors with property $\varGamma$ and for free-product factors.