Ramanujan and Extensions and Contractions of Continued Fractions

If a continued fraction $K_{n=1}^{\infty} a_{n}/b_{n}$ is known to converge but its limit is not easy to determine, it may be easier to use an extension of $K_{n=1}^{\infty}a_{n}/b_{n}$ to find the limit. By an extension of $K_{n=1}^{\infty} a_{n}/b_{n}$ we mean a continued fraction $K_{n=1}^{\infty} c_{n}/d_{n}$ whose odd or even part is $K_{n=1}^{\infty} a_{n}/b_{n}$. One can then possibly find the limit in one of three ways: (i) Prove the extension converges and find its limit; (ii) Prove the extension converges and find the limit of the other contraction (for example, the odd part, if $K_{n=1}^{\infty}a_{n}/b_{n}$ is the even part); (ii) Find the limit of the other contraction and show that the odd and even parts of the extension tend to the same limit. We apply these ideas to derive new proofs of certain continued fraction identities of Ramanujan and to prove a generalization of an identity involving the Rogers-Ramanujan continued fraction, which was conjectured by Blecksmith and Brillhart.Comment: 16 page

Relationship between visual field loss and maximal combined electroretinographic responses in retinitis pigmentosa : comparison among genetically different types

1984年から1996年までに千葉大学眼科を受診した定型網膜色素変性症228例について常優26例, 常劣64例, 孤発例138例に分け動的量的視野および網膜電図を検討した。Goldmann視野におけるV-4イソプターでは5から10cm^2までと150から250cm^2までの2群に別れ, 1-4イソプターでは5cm^2以下の群のみ認められた。加齢及び遺伝形式による差異は認められなかった。網膜電図ではa, b波ともに正常対照群より減少してはいるものの, 遺伝形式による差異は認められなかった。また, 網膜電図で振幅を認められる割合はV-4イソプターおよびI-4イソプターの面積と相関していることが示唆されたが, 遺伝形式による差異は認められなかった。網膜電図の振幅の比であるb/a比は正常対象群に対して疾患群は減少していたが, 常備は特に他に比べ有意に減少していた。定型網膜色素変性症の網膜電図や視野の検討は数多くなされてきたが, b/a比について統計的考察がなされてきたことはない。a波およびb波は組織学的に発生起源が異なっており, b波はa波のインパルスによって二次的に引き起こされることは以前より知られてきている。網膜電図において常備のb/a比が有意な低下を示すことは, 網膜障害の機序が他と異なる可能性が示唆された。Analyses were performed on 228 Japanese patients with retinitis pigmentosa (RP) who were classified with autosomal dominant (ADRP, n=26), autosomal recessive (ARRP, n=64), and simplex (simplex RP, rc=138) inheritance. Visual fields were tested with Goldmann perimetry. Maximal combined responses of electroretinogram (ERG) with 20-Joule white flash stimulation were recorded after dark adaptation for 20 minutes. The visual field with the V-4 isopter demonstrated two unique groups, represented by dense areas between 5 and 10cm^2 and between 150 and 250cm^2, while only one unique group was observed within the 5cm^2 area with the 1-4 isopter. No age or inheritance type of effect was seen. A-and b-wave amplitudes were equally low in the 3 groups, as compared with normal subjects. The b/a ratio was significantly smaller in the ADRP group, compared with the others. The rate of detectable ERG responses decreased as the visual field became smaller. There was no inheritance effect. A lower b/a ratio in ADRP patients suggested that retinal functional abnormalities differed from ARRP and simplex RP patients

Data Standards for the Genomes to Life Program

Existing GTL Projects already have produced volumes of dataand, over the course of the next five years, will produce an estimatedhundreds, or possibly thousands, of terabytes of data from hundreds ofexperiments conducted at dozens of laboratories in National Labs anduniversities across the nation. These data will be the basis forpublications by individual researchers, research groups, andmulti-institutional collaborations, and the basis for future DOEdecisions on funding further research in bioremediation. The short-termand long-term value of the data to project participants, to the DOE, andto the nation depends, however, on being able to access the data and onhow, or whether, the data are archived. The ability to access data is thestarting point for data analysis and interpretation, data integration,data mining, and development of data-driven models. Limited orinefficient data access means that less data are analyzed in acost-effective and timely manner. Data production in the GTL Program willlikely outstrip, or may have already outstripped, the ability to analyzethe data. Being able to access data depends on two key factors: datastandards and implementation of the data standards. For the purpose ofthis proposal, a data standard is defined as a standard, documented wayin which data and information about the data are describe. The attributesof the experiment in which the data were collected need to be known andthe measurements corresponding to the data collected need to bedescribed. In general terms, a data standard could be a form (electronicor paper) that is completed by a researcher or a document that prescribeshow a protocol or experiment should be described in writing.Datastandards are critical to data access because they provide a frameworkfor organizing and managing data. Researchers spend significant amountsof time managing data and information about experiments using labnotebooks, computer files, Excel spreadsheets, etc. In addition, dataoutput format varies for different equipment and usually need to beformatted differently for the variety of computer programs used todisplay and analyze the data. If, however, data for a given type ofexperiment were converted from vendor format to a format defined by adata standard, then researchers and software developers could save time.In addition, if data and information describing how they were obtainedwere available in a consistent format throughout the GTL Program,comparison and integration of results would be facilitated and a datarepository could be built to encourage project-wide data mining.Datastandards also are essential for archiving data sets. If data are storedtogether with the experiment metadata (i.e., information about the data)in an 'information/data package', then the data retain their value due tothe accessibility of information about measurement and analysisprocedures.DOE's commitment to developing data standards for the GTLProgram is needed to ensure that the most value is obtained from DOE'sexpenditures on experimental work and to provide a data repository thatcan be used as the basis for on-going model development. By developingdata standards for experiments conducted as part of the GTL Program, DOEhas the opportunity to facilitate data sharing not only within the DOEcommunity, but also with research institutes through theworld

Killer whales and marine mammal trends in the North Pacific : a re-examination of evidence for sequential megafauna collapse and the prey-switching hypothesis

This paper is not subject to U.S. copyright. The definitive version was published in Marine Mammal Science 23 (2007): 766–802, doi:10.1111/j.1748-7692.2006.00093.x.Springer et al. (2003) contend that sequential declines occurred in North Pacific populations of harbor and fur seals, Steller sea lions, and sea otters. They hypothesize that these were due to increased predation by killer whales, when industrial whaling's removal of large whales as a supposed primary food source precipitated a prey switch. Using a regional approach, we reexamined whale catch data, killer whale predation observations, and the current biomass and trends of potential prey, and found little support for the prey-switching hypothesis. Large whale biomass in the Bering Sea did not decline as much as suggested by Springer et al., and much of the reduction occurred 50–100 yr ago, well before the declines of pinnipeds and sea otters began; thus, the need to switch prey starting in the 1970s is doubtful. With the sole exception that the sea otter decline followed the decline of pinnipeds, the reported declines were not in fact sequential. Given this, it is unlikely that a sequential megafaunal collapse from whales to sea otters occurred. The spatial and temporal patterns of pinniped and sea otter population trends are more complex than Springer et al. suggest, and are often inconsistent with their hypothesis. Populations remained stable or increased in many areas, despite extensive historical whaling and high killer whale abundance. Furthermore, observed killer whale predation has largely involved pinnipeds and small cetaceans; there is little evidence that large whales were ever a major prey item in high latitudes. Small cetaceans (ignored by Springer et al.) were likely abundant throughout the period. Overall, we suggest that the Springer et al. hypothesis represents a misleading and simplistic view of events and trophic relationships within this complex marine ecosystem

Research Staff COVID-19 Pandemic Survey-Results from the Prevention and Early Treatment of Acute Lung Injury (PETAL) Network

Objectives: There is a lack of knowledge about the challenges of researchers who continued in-person research during the early phases of the COVID-19 pandemic. Design: Electronic survey assessing work-related exposure to COVID-19, logistical challenges, and procedural changes during the first year of the COVID-19 pandemic on clinical research. Setting: National Heart, Lung, and Blood Institute-sponsored Prevention and Early Treatment of Acute Lung Injury Clinical Trial Network Centers. Subjects: Research staff at research Network Sites. Measurements and Main Results: The 37-question survey was completed by 277 individuals from 24 states between 29 September 2020, and 12 December 2020, yielding a response rate of 37.7%. Most respondents (91.5%) indicated that non-COVID-19 research was affected by COVID-19 research studies. In response to the COVID-19 pandemic, 20% of respondents were reassigned to different roles at their institution. Many survey takers were exposed to COVID-19 (56%), with more than 50% of researchers requiring a COVID-19 test and 8% testing positive. The fear of infection was 2.7-times higher compared to pre-COVID-19 times. Shortages of personal protective equipment were encountered by 34% of respondents, primarily due to lack of access to N95 masks, followed by gowns and protective eyewear. Personal protective equipment reallocation from research to clinical use was reported by 31% of respondents. Most of the respondents (88.5%), despite these logistical challenges, indicated their willingness to enroll COVID-19 patients. Conclusions: During the first year of the COVID-19 pandemic, members of the research network were engaged in COVID-19 research despite logistical challenges, limited access to personal protective equipment, and fear of exposure. The research network’s survey experience can inform ongoing policy discussions to create research enterprises that can dexterously refocus research to address the knowledge gaps associated with novel public health emergencies while mitigating the effect of pandemics on existing research projects and research personnel

Expressions 1992

https://openspace.dmacc.edu/expressions/1014/thumbnail.jp

Suppression of circulating IgD+CD27+ memory B cells in infants living in a malaria-endemic region of Kenya

Background: Plasmodium falciparum infection leads to alterations in B cell subset distribution. During infancy, development of peripheral B cell subsets is also occurring. However, it is unknown if infants living a malaria endemic region have alterations in B cell subsets that is independent of an age effect. Methods: To evaluate the impact of exposure to P. falciparum on B cell development in infants, flow cytometry was used to analyse the distribution and phenotypic characteristic of B cell subsets in infant cohorts prospectively followed at 12, 18 and 24 months from two geographically proximate regions in western Kenya with divergent malaria exposure i.e. Kisumu (malaria-endemic, n = 24) and Nandi (unstable malaria transmission, n = 21). Results: There was significantly higher frequency and absolute cell numbers of CD19+ B cells in Kisumu relative to Nandi at 12(p = 0.0440), 18(p = 0.0210) and 24 months (p = 0.0493). No differences were observed between the infants from the two sites in frequencies of naïve B cells (IgD+CD27-) or classical memory B cells (IgD-CD27+). However, immature transitional B cells (CD19+CD10+CD34-) were higher in Kisumu relative to Nandi at all three ages. In contrast, the levels of non-class switched memory B cells (CD19+IgD+CD27+) were significantly lower overall in Kisumu relative to Nandi at significantly at 12 (p = 0.0144), 18 (p = 0.0013) and 24 months (p = 0.0129). Conclusions: These data suggest that infants living in malaria endemic regions have altered B cell subset distribution. Further studies are needed to understand the functional significance of these changes and long-term impact on ability of these infants to develop antibody responses to P. falciparum and heterologous infections

Introduction : narcissism, melancholia and the subject of community.

Sigmund Freud’s twin papers, ‘On Narcissism: An Introduction’ (1914) and ‘Mourning and Melancholia’ (1917 [1915]), take as their formative concern the difficulty of setting apart the ‘inner’ and the ‘outer’ worlds, and of preserving a stable image of a boundaried self. Whilst it is true that the term narcissism especially has come to be deployed in ways that seem foreign to the complexities of Freud’s 1914 paper (by its reduction to a personality disorder or its use as a broad-brush cultural diagnosis), we suggest in this introductory chapter that neither narcissism nor melancholia can be thought about today without expressing some debt to Freudian metapsychology. However, whereas Freud was most evidently concerned to describe the structure of ego-formation, subsequent commentators have preferred to emphasize the cultural and normative dimensions of these terms. Accordingly, we consider the respective discursive histories of narcissism and melancholia and find that although they have been put to work in very different ways they remain grounded by a shared concern with mechanisms of relation and identification. Indeed, this shared concern is the basis upon which they’ve been most productively reanimated in recent years: the rise of melancholia as a critical aid to the study of cultural displacement and dispossession, and the determined redemption of narcissism from its pejorative characterization as fundamentally anti-social. We argue that what is most noteworthy in this post-Freudian literature is the increasing relevance of metapsychology to social and political theory. The language of psychoanalysis, extrapolated from the clinic, permits a detailed examination of the boundaries which construct and challenge the terms of social solidarity. Specifically, this takes place though careful reading of the complex practices of (dis)identification at the heart of ego-formation (at both individual and group levels), and the associated mechanisms of defence, for example: introjection, incorporation, projective-identification, and splitting. By recognising the complexity of how communities get made, and connecting this with recent literature on counter publics and the commons, we demonstrate that Freud’s frameworks of narcissism and melancholia remain essential for any contemporary understanding of political association

Exercise and Stress Management Training Prior to Hematopoietic Cell Transplantation: Blood and Marrow Transplant Clinical Trials Network (BMT CTN) 0902

Studies show that engaging patients in exercise and/or stress management techniques during hematopoietic cell transplantation (HCT) improves quality of life. The Blood and Marrow Transplant Clinical Trials Network tested the efficacy of training patients to engage in self-directed exercise and stress management during their HCTs. The study randomized 711 patients at 21 centers to receive one of four training interventions before HCT: a self-directed exercise program, a self-administered stress management program, both or neither. Participants completed self-reported assessments at enrollment and up to 180 days after transplant. Randomization was stratified by center and transplant type. There were no differences in the primary endpoints of the physical (PCS) and mental (MCS) component scales of the SF36 at day 100 among the groups based on an intention-to-treat analysis. There were no differences observed in overall survival, hospital days through day 100 post-HCT, or in other patient-reported outcomes, including treatment-related distress, sleep quality, pain, and nausea. Patient randomized to training in stress management reported more use of those techniques; patients randomized to training in exercise did not report more physical activity. Although other studies have reported efficacy of more intensive interventions, brief training in an easy-to-disseminate format for either self-directed exercise or stress management was not effective in our trial