Últimos itens adicionados do Acervo: Harvard University

A Universidade de Harvard (em inglês: Harvard University) é uma universidade privada membro da Ivy League, localizada em Cambridge, Massachusetts, Estados Unidos, e cuja história, influência e riqueza tornam-a uma das mais prestigiadas universidades do mundo.

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‣ Novel Molecular Investigations Into: (1) Obstructive Sleep Apnea and (2) De Novo Postpartum Hypertension

Maski, Manish R.
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation; text Formato: application/pdf
Português
There are two themes of the work herein presented: (1) exploration of the molecular pathophysiology of obstructive sleep apnea (OSA), and (2) the role of angiogenic factors in selected diseases, including OSA, de novo hypertension developing in the postpartum period (de novo PPHTN), and diabetic nephropathy.

‣ A Qualitative Study Exploring the Experience of Women Seeking Care for Breast Cancer in Haiti

Belizaire, Nadege
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation; text Formato: application/pdf
Português
Objectives: This study elucidates factors that affect access to care and the journey from first symptoms to treatment for Haitian women diagnosed with late-stage breast cancer. This study identifies structural barriers that women with late-stage diagnosis faced. Identification of these barriers can inform interventions that facilitate prompt diagnosis and lead to improved outcomes. Methods: In this qualitative study, we selected participants from the Hôpital Universitaire de Mirebalais. We conducted and audio-recorded 18 interviews in Haitian Creole. Data were transcribed and translated into English. Qualitative data analysis examined multiple viewpoints using narrative analysis and grounded theory. Results: The findings highlight the patients’ pelerinaj (journey): they visited several health facilities—expending considerable time, energy, and money—before being able to access appropriate breast cancer care; patients experienced delays in their care trajectory which resulted in a loss of income and autonomy. Nevertheless, patients reported receiving important inputs—accompaniment, hope, moral and economic support—from their caregivers who were family members or friends.. Conclusion: Without structural interventions to improve access to high-quality and affordable breast-cancer care...

‣ Gait Recognition Using Encodings With Flexible Similarity Measures

Crouse, Michael B; Chen, Kevin; Kung, H. T.
Fonte: USENIX Publicador: USENIX
Tipo: Conference Paper
Português
Gait signals detectable by sensors on ubiquitous personal devices such as smartphones can reveal characteristics unique to each individual, and thereby offer a new approach to recognizing users. Conventional pattern matching approaches use inner-product based distance measures which are not robust to common variations in time-series analysis (e.g., shifts and stretching). This is unfortunate given that it is well understood that capturing such variations is paramount for model performance. This work shows how machine learning methods which encode gait signals into a feature space based on a dictionary can use convolution and Dynamic TimeWarping (DTW) similarity measures to improve classification accuracy in a variety of situations common to gait recognition. We also show that data augmentation is crucial in gait recognition, as diverse training data in practical applications is very limited. We validate the effectiveness of these methods empirically, and demonstrate the identification of user gait patterns where shift and stretch variations in measurements are substantial. We present a new gait dataset that contains a complete representation of the variations that can be expected in real-world recognition scenarios. We compare our techniques against the current state of the art gait period detection and normalization schemes on our dataset and show improved classification accuracy under all experimental scenarios.; Engineering and Applied Sciences

‣ Zen Master Toko Shinetsu's Contributions through Cultural Exchange between China and Japan in Regards to Guqin Music

Lee, Mei-Yen
Fonte: Harvard University Publicador: Harvard University
Tipo: Conference Paper
Português
History

‣ Delaware's Choice

Subramanian, Guhan
Fonte: Harvard University Publicador: Harvard University
Tipo: Research Paper or Report
Português
This Article first documents the shift to annual elections of all directors at most U.S. corporations, and argues that the alternative of "ineffective" staggered boards would have been more desirable, as a policy matter, but is now a missed opportunity. Using this experience on staggered boards as a motivating case study, the Article then examines a policy choice regarding Section 203 of the Delaware General Corporation Law. Four facts are uncontested: (1) in the 1980s, federal courts established the principle that Section 203 must give bidders a "meaningful opportunity for success" in order to withstand scrutiny under the Supremacy Clause of the U.S. Constitution; (2) federal courts upheld Section 203 at the time, based on empirical evidence from 1985-1988 purporting to show that Section 203 did in fact give bidders a meaningful opportunity for success; (3) between 1990 and 2010, not a single bidder was able to achieve the 85% threshold required by Section 203, thereby calling into question whether Section 203 has in fact given bidders a meaningful opportunity for success; and (4) perhaps most damning, the original evidence that the courts relied upon to conclude that Section 203 gave bidders a meaningful opportunity for success was seriously flawed-so flawed...

‣ Easy Freshness with Pequod Cache Joins

Kate, Bryan; Kohler, Eddie W; Kester, Michael S; Narula, Neha; Mao, Yandong; Morris, Robert
Fonte: USENIX Publicador: USENIX
Tipo: Conference Paper
Português
Pequod is a distributed application-level key-value cache that supports declaratively defined, incrementally maintained, dynamic, partially-materialized views. These views, which we call cache joins, can simplify application development by shifting the burden of view maintenance onto the cache. Cache joins define relationships among key ranges; using cache joins, Pequod calculates views on demand, incrementally updates them as required, and in many cases improves performance by reducing client communication. To build Pequod, we had to design a view abstraction for volatile, relationless key-value caches and make it work across servers in a distributed system. Pequod performs as well as other inmemory key-value caches and, like those caches, outperforms databases with view support.; Engineering and Applied Sciences

‣ Fast Databases with Fast Durability and Recovery Through Multicore Parallelism

Zheng, Wenting; Tu, Stephen; Kohler, Eddie W; Liskov, Barbara
Fonte: USENIX Publicador: USENIX
Tipo: Conference Paper
Português
Multicore in-memory databases for modern machines can support extraordinarily high transaction rates for online transaction processing workloads. A potential weakness, however, is recovery from crash failures. Can classical techniques, such as checkpoints, be made both efficient enough to keep up with current systems’ memory sizes and transaction rates, and smart enough to avoid additional contention? Starting from an efficient multicore database system, we show that naive logging and checkpoints make normal-case execution slower, but that frequent disk synchronization allows us to keep up with many workloads with only a modest reduction in throughput. We design throughout for parallelism: during logging, during checkpointing, and during recovery. The result is fast. Given appropriate hardware (three SSDs and a RAID), a 32-core system can recover a 43.2 GB key-value database in 106 seconds, and a > 70 GB TPC-C database in 211 seconds.; Engineering and Applied Sciences

‣ Phase Reconciliation for Contended In-Memory Transactions

Narula, Neha; Cutler, Cody; Kohler, Eddie W; Morris, Robert
Fonte: USENIX Publicador: USENIX
Tipo: Conference Paper
Português
Multicore main-memory database performance can collapse when many transactions contend on the same data. Contending transactions are executed serially—either by locks or by optimistic concurrency control aborts—in order to ensure that they have serializable effects. This leaves many cores idle and performance poor. We introduce a new concurrency control technique, phase reconciliation, that solves this problem for many important workloads. Doppel, our phase reconciliation database, repeatedly cycles through joined, split, and reconciliation phases. Joined phases use traditional concurrency control and allow any transaction to execute. When workload contention causes unnecessary serial execution, Doppel switches to a split phase. There, updates to contended items modify per-core state, and thus proceed in parallel on different cores. Not all transactions can execute in a split phase; for example, all modifications to a contended item must commute. A reconciliation phase merges these per-core states into the global store, producing a complete database ready for joined phase transactions. A key aspect of this design is determining which items to split, and which operations to allow on split items. Phase reconciliation helps most when there are many updates to a few popular database records. Its throughput is up to 38x higher than conventional concurrency control protocols on microbenchmarks...

‣ Beyond Feature Relevance: Incorporating Rich User Feedback Into Interactive Machine Learning Applications

Gajos, Krzysztof Z
Fonte: Harvard University Publicador: Harvard University
Tipo: Conference Paper
Português
Engineering and Applied Sciences

‣ Opportunities for Intelligent Interfaces Aiding Healthcare in Low-Income Countries

DeRenzi, Brian; Gajos, Krzysztof Z; Parikh, Tapan S.; Lesh, Neal; Mitchell, Marc D.; Borriello, Gaetano
Fonte: Association for Computing Machinery Publicador: Association for Computing Machinery
Tipo: Conference Paper
Português
Child mortality is one of the most pressing health concerns almost 10 million children die worldwide each year before reaching their fifth birthday, mostly in low-income countries. To aid overburdened and undertrained health workers the World Health Organization (WHO) and United Nations Children's Fund (UNICEF) have developed clinical guidelines, such as the Integrated Management of Childhood Illness (IMCI) to help with the classification and treatment of common childhood illness. To help with deployment, we have developed an electronic version (e-IMCI) that runs on a PDA. From July to September 2007, we ran a pilot of e-IMCI in southern Tanzania. The system guides health workers step-by-step through the treatment algorithms and automatically calculates drug doses. Our results suggest that electronic implementations of protocols such as IMCI can reduce training time and improve adherence to the protocol. They also highlight several important challenges including varying levels of education, language and expertise, which could be most adequately addressed by implementing novel intelligent user interfaces and systems.; Engineering and Applied Sciences

‣ Vitamin D deficiency contributes directly to the acute respiratory distress syndrome (ARDS)

Dancer, Rachel C A; Parekh, Dhruv; Lax, Sian; D'Souza, Vijay; Zheng, Shengxing; Bassford, Chris R; Park, Daniel; Bartis, D G; Mahida, Rahul; Turner, Alice M; Sapey, Elizabeth; Wei, Wenbin; Naidu, Babu; Stewart, Paul M; Fraser, William D; Christopher, Kenn
Fonte: BMJ Publishing Group Publicador: BMJ Publishing Group
Tipo: Artigo de Revista Científica
Português
Rationale: Vitamin D deficiency has been implicated as a pathogenic factor in sepsis and intensive therapy unit mortality but has not been assessed as a risk factor for acute respiratory distress syndrome (ARDS). Causality of these associations has never been demonstrated. Objectives: To determine if ARDS is associated with vitamin D deficiency in a clinical setting and to determine if vitamin D deficiency in experimental models of ARDS influences its severity. Methods: Human, murine and in vitro primary alveolar epithelial cell work were included in this study. Findings: Vitamin D deficiency (plasma 25(OH)D levels <50 nmol/L) was ubiquitous in patients with ARDS and present in the vast majority of patients at risk of developing ARDS following oesophagectomy. In a murine model of intratracheal lipopolysaccharide challenge, dietary-induced vitamin D deficiency resulted in exaggerated alveolar inflammation, epithelial damage and hypoxia. In vitro, vitamin D has trophic effects on primary human alveolar epithelial cells affecting >600 genes. In a clinical setting, pharmacological repletion of vitamin D prior to oesophagectomy reduced the observed changes of in vivo measurements of alveolar capillary damage seen in deficient patients. Conclusions: Vitamin D deficiency is common in people who develop ARDS. This deficiency of vitamin D appears to contribute to the development of the condition...

‣ Provenance for the Cloud

Muniswamy-Reddy, Kiran-Kumar; Macko, Peter; Seltzer, Margo I.
Fonte: The USENIX Association Publicador: The USENIX Association
Tipo: Conference Paper
Português
The cloud is poised to become the next computing environment for both data storage and computation due to its pay-as-you-go and provision-as-you-go models. Cloud storage is already being used to back up desktop user data, host shared scientific data, store web application data, and to serve web pages. Today’s cloud stores, however, are missing an important ingredient: provenance. Provenance is metadata that describes the history of an object. We make the case that provenance is crucial for data stored on the cloud and identify the properties of provenance that enable its utility. We then examine current cloud offerings and design and implement three protocols for maintaining data/provenance in current cloud stores. The protocols represent different points in the design space and satisfy different subsets of the provenance properties. Our evaluation indicates that the overheads of all three protocols are comparable to each other and reasonable in absolute terms. Thus, one can select a protocol based upon the properties it provides without sacrificing performance. While it is feasible to provide provenance as a layer on top of today’s cloud offerings, we conclude by presenting the case for incorporating provenance as a core cloud feature...

‣ Lycian statti `stands'

Jasanoff, Jay H.
Fonte: Harrassowitz Publicador: Harrassowitz
Tipo: Monograph or Book
Português
Linguistics

‣ Memory Troubles: Remembering the Occupation in Simone de Beauvoir's Les Mandarins

Suleiman, Susan Rubin
Fonte: Berghahn Journals Publicador: Berghahn Journals
Tipo: Artigo de Revista Científica
Português
Critics generally agree that Beauvoir's novel Les Mandarins, which won the Prix Goncourt in 1954, is an important work of historical fiction, chronicling the lives and loves of left-wing intellectuals in Paris during the years following World War II. In this essay I argue that Les Mandarins is as much about the war as about the postwar, and that its meaning for contemporary readers was deeply linked (even if not in a fully recognized way) to memories of the troubled period of the Occupation. I develop the concept of “ambivalent memory,” as it refers in particular to two of the most problematic aspects of that period: the role of the Vichy government in the persecution of Jews, and the ambiguities and disagreements concerning the Resistance. More generally, the novel raises questions about memory and its inevitable obverse, forgetting. It is from our own contemporary perspective, heavily informed by concerns over memory and World War II, that this aspect of Les Mandarins comes to the fore.; Literature and Comparative Literature

‣ Towards Query interoperability: PASSing PLUS

Braun, Uri Jacob; Seltzer, Margo I.; Chapman, Adriane; Blaustein, Barbara; Allen, M. David; Seligman, Len
Fonte: USENIX Association Publicador: USENIX Association
Tipo: Conference Paper
Português
We describe our experiences importing PASS [16] provenance into PLUS [7]. Although both systems import and export provenance that conforms to the Open Provenance Model (OPM) [14], the two systems vary greatly with respect to the granularity of provenance captured, how much semantic knowledge the system contributes, and the completeness of provenance capture. We encountered several problems reconciling provenance between the two systems and use that experience to specify a Common Provenance Framework, that provides a higher degree of interoperability between provenance systems. In each case, the problems stem from the fact that OPM interoperability is a weaker requirement than query interoperability. Our goal in presenting this work is to generate discussion about differing degrees of interoperability and the requirements thereof.; Engineering and Applied Sciences

‣ Classical Racism, Justice Story, and Margaret Morgan's Journey from Freedom to Slavery: The Story of Prigg v. Pennsylvania

Sullivan Jr., Ronald S.
Fonte: Foundation Press Publicador: Foundation Press
Tipo: Monograph or Book
Português

‣ Immunodominant HIV-1-specific HLA-B- and HLA-C-restricted CD8+ T cells do not differ in polyfunctionality

Mkhwanazi, Nompumelelo; Thobakgale, Christina F.; van der Stok, Mary; Reddy, Shabashini; Mncube, Zenele; Chonco, Fundisiwe; Ndung'u, Thumbi; Walker, Bruce David; Altfeld, Marcus; Goulder, Philip J.
Fonte: Academic Press Publicador: Academic Press
Tipo: Artigo de Revista Científica
Português
HIV-1 specific HLA-B-restricted CD8+ T cell responses differ from HLA-C-restricted responses in antiviral effectiveness. To investigate possible reasons for these differences, we characterized the frequency and polyfunctionality of immmunodominant HLA-B*57/B5801- and HLA-Cw*07-restricted CD8+ T cells occurring concurrently in nine study subjects assessing IFN-γ, TNF-α, IL-2, MIP-1β, and CD107a by flow cytometry and analyzed sequence variation in targeted epitopes. HLA-B*57/5801 and HLA-Cw*07 restricted CD8+ T cells did not differ significantly in polyfunctionality (p = 0.84). Possession of three or more functions correlated positively with CD4+ T cell counts (r = 0.85; p = 0.006) and monofunctional CD8+ T cells inversely correlated with CD4 cell counts (r = −0.79; p = 0.05). There were no differences in polyfunctionality of CD8+ T cells specific to wildtype versus mutated epitopes. These results suggest that loss of polyfunctionality and increase in monofunctional HIV-1-specific CD8+ T cells are associated with disease progression independent of restricting HLA allele. Furthermore, sequence variation does not appear to significantly impact CD8+ T cell polyfunctionality in chronic HIV-1 infection.

‣ Urinary 8-hydroxy-2'-deoxyguanosine as a biomarker of oxidative DNA damage in workers exposed to fine particulates.

Mukherjee, Sutapa; Ngo, Long H.; Christiani, David C.; Kim, Jee Young
Fonte: National Institute of Environmental Health Sciences Publicador: National Institute of Environmental Health Sciences
Tipo: Artigo de Revista Científica
Português
Residual oil fly ash (ROFA) is a chemically complex mixture of compounds, including metals that are potentially carcinogenic because of their ability to cause oxidative injury. In this study, we investigated the association between exposure to particulate matter with an aerodynamic mass median diameter ≤ 2.5 micro m (PM2.5) and oxidative DNA damage and repair, as indicated by urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentrations, in a group of boilermakers exposed to ROFA and metal fumes. Twenty workers (50% smokers) were monitored for 5 days during an overhaul of oil-fired boilers. The median occupational PM2.5 8-hr time-weighted average was 0.44 mg/m3 (25th-75th percentile, 0.29-0.76). The mean ± SE creatinine-adjusted 8-OHdG levels were 13.26 ± 1.04 micro μg/g in urine samples collected pre-workshift and 15.22 ± 0.99 micro μg/g in the post-workshift samples. The urinary 8-OHdG levels were significantly greater in the post-workshift samples than in the pre-workshift samples (p = 0.02), after adjusting for urinary cotinine levels, chronic bronchitis status, and age. Linear mixed models indicated a significant exposure-response association between PM2.5 exposure and urinary 8-OHdG levels (p = 0.03). Each 1-mg/m3 incremental increase in PM2.5 exposure was associated with an increase of 1.67 micro μg/g (95% confidence interval...

‣ p63 promotes cell survival through fatty acid synthase

Di Napoli, Arianna; Seeley, Apryle; Amato, Angela M.; O'Regan, Esther; Sabbisetti, Venkata S; Ghebremichael, Musie Syum; Loda, Massimo; Signoretti, Sabina
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
There is increasing evidence that p63, and specifically ΔNp63, plays a central role in both development and tumorigenesis by promoting epithelial cell survival. However, few studies have addressed the molecular mechanisms through which such important function is exerted. Fatty acid synthase (FASN), a key enzyme that synthesizes long-chain fatty acids and is involved in both embryogenesis and cancer, has been recently proposed as a direct target of p53 family members, including p63 and p73. Here we show that knockdown of either total or ΔN-specific p63 isoforms in squamous cell carcinoma (SCC9) or immortalized prostate epithelial (iPrEC) cells caused a decrease in cell viability by inducing apoptosis without affecting the cell cycle. p63 silencing significantly reduced both the expression and the activity of FASN. Importantly, stable overexpression of either FASN or myristoylated AKT (myr-AKT) was able to partially rescue cells from cell death induced by p63 silencing. FASN induced AKT phosphorylation and a significant reduction in cell viability was observed when FASN-overexpressing SCC9 cells were treated with an AKT inhibitor after p63 knockdown, indicating that AKT plays a major role in FASN-mediated survival. Activated AKT did not cause any alteration in the FASN protein levels but induced its activity...

‣ Five Theses on Identity Politics

Parker, Richard D.
Fonte: Harvard Society for Law and Public Policy Publicador: Harvard Society for Law and Public Policy
Tipo: Artigo de Revista Científica
Português