Shifted distinct-part partition identities in arithmetic progressions

The partition function $p(n)$, which counts the number of partitions of a positive integer $n$, is widely studied. Here, we study partition functions $p_S(n)$ that count partitions of $n$ into distinct parts satisfying certain congruence conditions. A shifted partition identity is an identity of the form $p_{S_1}(n-H) = p_{S_2}(n)$ for all $n$ in some arithmetic progression. Several identities of this type have been discovered, including two infinite families found by Alladi. In this paper, we use the theory of modular functions to determine the necessary and sufficient conditions for such an identity to exist. In addition, for two specific cases, we extend Alladi's theorem to other arithmetic progressions

Liquid droplet formation by HP1α suggests a role for phase separation in heterochromatin.

Gene silencing by heterochromatin is proposed to occur in part as a result of the ability of heterochromatin protein 1 (HP1) proteins to spread across large regions of the genome, compact the underlying chromatin and recruit diverse ligands. Here we identify a new property of the human HP1α protein: the ability to form phase-separated droplets. While unmodified HP1α is soluble, either phosphorylation of its N-terminal extension or DNA binding promotes the formation of phase-separated droplets. Phosphorylation-driven phase separation can be promoted or reversed by specific HP1α ligands. Known components of heterochromatin such as nucleosomes and DNA preferentially partition into the HP1α droplets, but molecules such as the transcription factor TFIIB show no preference. Using a single-molecule DNA curtain assay, we find that both unmodified and phosphorylated HP1α induce rapid compaction of DNA strands into puncta, although with different characteristics. We show by direct protein delivery into mammalian cells that an HP1α mutant incapable of phase separation in vitro forms smaller and fewer nuclear puncta than phosphorylated HP1α. These findings suggest that heterochromatin-mediated gene silencing may occur in part through sequestration of compacted chromatin in phase-separated HP1 droplets, which are dissolved or formed by specific ligands on the basis of nuclear context

Speaking vocabulary of first grade children

Thesis (Ed.M.)--Boston Universit

Greater Number of Weekly Stairs Climbed is Associated With Lower Low Back Pain Prevalence Among Female but not Male Physical Therapists

INTRODUCTION: Certain cardiovascular health benefits of stair climbing are now widely accepted, but no prior studies have as yet been found linking the quantity of stairs climbed to low back pain (LBP) morbidity. Low back pain is a common musculoskeletal impairment, and research has begun to show an association between LBP and gluteus maximus (GM) weakness. With stair climbing being the activity which most activates GM, the aim of the present research was to assess the relationship between stair ambulation and LBP prevalence. The hypothesis of this cross-sectional study was that individuals with LBP would report a significantly lower numbers of stair flights climbed compared with individuals without LBP. METHODS: A survey tool was developed and distributed via email to a convenience sample of orthopedic physical therapists. Survey items included information regarding medical history, physical activity, workplace, and LBP factors, using a one-year prevalence period. RESULTS: A total of 363 respondents took the survey and, after application of exclusion criteria, 248 records remained in our final sample. When analyzing all genders together, non LBP (NLBP) respondents reported a mean of 51.62 flights climbed per week; and LBP respondents reported 37.82 flights climbed per week, with P = 0.077. When males and females were analyzed separately, a statistically significant difference in mean number of flights of stairs climbed was found among female respondents (61.51 flights climbed for NLBP and 35.61 flights climbed for LBP females; P = 0.031). When analyzed based on chronicity of LBP, an even stronger association between stairs climbed and LBP prevalence was found for female respondents with acute LBP (P = 0.009). CONCLUSIONS: More weekly stairs climbed was associated with a lower LBP prevalence among females, especially with respect to acute LBP. Randomized, longitudinal research is, however, required to confirm a relationship between stair climbing and LBP

Middle managers’ role in implementing evidence-based practices in healthcare: a systematic review

Abstract Background Middle managers are in a unique position to promote the implementation of evidence-based practices (EBPs) in healthcare organizations, yet knowledge of middle managers’ role in implementation and determinants (e.g., individual-, organizational-, and system-level factors) which influence their role remains fractured, spanning decades and disciplines. To synthesize understanding, we undertook a systematic review of studies of middle managers’ role in healthcare EBP implementation and determinants of that role. Methods We searched MEDLINE/PubMed and Business Source Complete (Ebsco) for literature on middle managers’ role in healthcare EBP implementation and its determinants. We abstracted data from records that met inclusion criteria (i.e., written in English, peer-reviewed, and reporting either a protocol or results of an empirical study) into a matrix for analysis. We summarized categorical variables using descriptive statistics. To analyze qualitative data, we used a priori codes and then allowed additional themes to emerge. Results One hundred five records, spanning across several countries and healthcare settings and relating to a range of EBPs, met our inclusion criteria. Studies of middle managers’ role in healthcare EBP implementation and its determinants substantially increased from 1996 to 2015. Results from included studies suggest that middle managers shape implementation climate in addition to fulfilling the four roles hypothesized in extant theory of middle managers’ role in implementation. However, extant studies offered little understanding of determinants of middle managers’ role. Conclusions Our findings suggest that middle managers may play an important role in facilitating EBP implementation. Included studies offered little understanding regarding the relative importance of various roles, potential moderators of the relationship between middle managers’ roles and EBP implementation, or determinants of middle managers’ role in EBP implementation. Future studies should seek to understand determinants and moderators of middle managers’ role. Clearer understanding may facilitate the translation of evidence into practice

Genome remodelling in a basal-like breast cancer metastasis and xenograft

Massively parallel DNA sequencing technologies provide an unprecedented ability to screen entire genomes for genetic changes associated with tumour progression. Here we describe the genomic analyses of four DNA samples from an African-American patient with basal-like breast cancer: peripheral blood, the primary tumour, a brain metastasis and a xenograft derived from the primary tumour. The metastasis contained two de novo mutations and a large deletion not present in the primary tumour, and was significantly enriched for 20 shared mutations. The xenograft retained all primary tumour mutations and displayed a mutation enrichment pattern that resembled the metastasis. Two overlapping large deletions, encompassing CTNNA1, were present in all three tumour samples. The differential mutation frequencies and structural variation patterns in metastasis and xenograft compared with the primary tumour indicate that secondary tumours may arise from a minority of cells within the primary tumour

Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed

Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation

The Pediatric Inventory for Parents : a systematic review of the psychometric properties and development of a short form.

The Pediatric Inventory for Parents (PIP) is a measure of pediatric parenting stress. In the present study, a systematic review of the psychometric properties of the PIP was conducted to determine if it was appropriate to create a short-form of the PIP. After this determination, a short-form of the PIP was developed under the Partial Credit Model (PCM). The PIP Short-Form was developed with a sample of fathers of children with type 1 diabetes (n = 251) and consists of 12 items that are each responded to for both frequency and difficulty. The retained items were chosen to reflect the content domains of the original form of the PIP and acceptable item fit under the PCM. The PIP Short-Form may allow health care professionals to more feasibly assess pediatric parenting stress among parents of children with chronic health conditions

The Round Table 03 圆桌: A Conversation with Xu Bing

The following is an excerpt from a conversation between contemporary Chinese artist Xu Bing, Madeline Eschenburg, and Ellen Larson. Xu Bing curated an exhibition at the Central Academy of Fine Arts titled The Second CAFAM Future Exhibition, Observer-Creator: The Reality Representation of Chinese Young Art, on exhibition through March 2015. Our conversation centered around his thoughts on a new generation of young Chinese artists as well as reflection on his own early career and time in New York. The conversation was conducted in Chinese and has been translated into English.</p