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We tested for transposition effects (TEs) in Hindi (a Modern Indo-Aryan language) using unprimed lexical decision. TEs are defined as less accurate and slower responses to transposed-nonwords (e.g., , formed from base-word ) than corresponding replaced-nonwords (e.g., ). In Hindi's orthography, letters map transparently to phonemes (except schwa), but the letters are arranged into "akshars," (n]V>) which encode open syllables. This formal characteristic makes Hindi's orthography typologically "aksharic." We used TEs to determine whether the orthography's typological units, letters and akshars, are also functional units for readers. We conducted three visual word recognition experiments with adult readers whose native language was Hindi. In Experiment 1, we found TEs for consonant () and matra (, a vowel diacritic) letters, using different stimulus sets for each type of transposition. In the next two experiments, we used the same base words to form all of the transposed and replaced items. In Experiment 2, we replicated the findings of Experiment 1 in a different stimulus set; additionally, we found TEs for transpositions between a letter and a akshar. In Experiment 3, we replicated results of the first two experiments by finding TEs for both consonants and matras in another stimulus set; additionally, we found similar TEs for akshars. These results show that and letters are functional units for Hindi readers; the transposition results for akshars are tentative. TEs for letters show that the aksharic grouping of letters does not prevent readers from decoding the constituent letters of akshars. Hindi is read alphabetically.
Assuntos
Idioma , Leitura , Adulto , Humanos , Reconhecimento Visual de Modelos , RedaçãoRESUMO
Palliative care (PC) and hospice services have experienced shortages before 2020, and during the initial phases of the current pandemic, more critical gaps are expected with future surges, much as scarcity in intensive care unit services may recur during the COVID-19 pandemic. Although ethical allocation of ventilators and intensive care unit care is the subject of important discussions during this pandemic, caring for those at the end of life and those not desiring or qualifying for critical interventions must not be neglected, as critical care and comfort-focused care are intertwined. We review state and regional gaps already recognized in planning for scarcity in PC and hospice services during this pandemic and describe the planning initiatives Colorado has developed to address potential scarcities for this vulnerable and diverse group of people. We hope to encourage other state and regional groups to anticipate needs in the coming surges of this pandemic or in public health crises to come. Such planning is key to avoid the degradation of care that may result if it is necessary to invoke crisis standards of care and ration these essential services to our communities.
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COVID-19 , Cuidados Paliativos na Terminalidade da Vida , Hospitais para Doentes Terminais , Colorado , Cuidados Críticos , Humanos , Cuidados Paliativos , Pandemias , SARS-CoV-2RESUMO
Several enzymes in cellular bioenergetics metabolism require NAD+ as an essential cofactor for their activity. NAD+ depletion following ischemic insult can result in cell death and has been associated with over-activation of poly-ADP-ribose polymerase PARP1 as well as an increase in NAD+ consuming enzyme CD38. CD38 is an NAD+ glycohydrolase that plays an important role in inflammatory responses. To determine the contribution of CD38 activity to the mechanisms of post-ischemic brain damage we subjected CD38 knockout (CD38KO) mice and wild-type (WT) mice to transient forebrain ischemia. The CD38KO mice showed a significant amelioration in both histological and neurologic outcome following ischemic insult. Decrease of hippocampal NAD+ levels detected during reperfusion in WT mice was only transient in CD38KO animals, suggesting that CD38 contributes to post-ischemic NAD+ catabolism. Surprisingly, pre-ischemic poly-ADP-ribose (PAR) levels were dramatically higher in CD38KO animals compared to WT animals and exhibited reduction post-ischemia in contrast to the increased levels in WT animals. The high PAR levels in CD38 mice were due to reduced expression levels of poly-ADP-ribose glycohydrolase (PARG). Thus, the absence of CD38 activity can not only directly affect inflammatory response, but also result in unpredicted alterations in the expression levels of enzymes participating in NAD+ metabolism. Although the CD38KO mice showed significant protection against ischemic brain injury, the changes in enzyme activity related to NAD+ metabolism makes the determination of the role of CD38 in mechanisms of ischemic brain damage more complex.
Assuntos
ADP-Ribosil Ciclase 1/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/prevenção & controle , Glicoproteínas de Membrana/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Animais , Células Cultivadas , Glicosídeo Hidrolases/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Distribuição AleatóriaRESUMO
Studies of speech accommodation provide evidence for change in use of language structures beyond the critical/sensitive period. For example, Sancier and Fowler (1997) found changes in the voice-onset-times (VOTs) of both languages of a Portuguese-English bilingual as a function of her language context. Though accommodation has been studied widely within a monolingual context, it has received less attention in and between the languages of bilinguals. We tested whether these findings of phonetic accommodation, speech accommodation at the phonetic level, would generalize to a sample of Spanish-English bilinguals. We recorded participants reading Spanish and English sentences after 3-4 months in the US and after 2-4 weeks in a Spanish speaking country and measured the VOTs of their voiceless plosives. Our statistical analyses show that participants' English VOTs drifted towards those of the ambient language, but their Spanish VOTs did not. We found considerable variation in the extent of individual participants' drift in English. Further analysis of our results suggested that native-likeness of L2 VOTs and extent of active language use predict the extent of drift. We provide a model based on principles of self-organizing dynamical systems to account for our Spanish-English phonetic drift findings and the Portuguese-English findings.
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We revisit an article, "Perception of the Speech Code" (PSC), published in this journal 50 years ago (Liberman, Cooper, Shankweiler, & Studdert-Kennedy, 1967) and address one of its legacies concerning the status of phonetic segments, which persists in theories of speech today. In the perspective of PSC, segments both exist (in language as known) and do not exist (in articulation or the acoustic speech signal). Findings interpreted as showing that speech is not a sound alphabet, but, rather, phonemes are encoded in the signal, coupled with findings that listeners perceive articulation, led to the motor theory of speech perception, a highly controversial legacy of PSC. However, a second legacy, the paradoxical perspective on segments has been mostly unquestioned. We remove the paradox by offering an alternative supported by converging evidence that segments exist in language both as known and as used. We support the existence of segments in both language knowledge and in production by showing that phonetic segments are articulatory and dynamic and that coarticulation does not eliminate them. We show that segments leave an acoustic signature that listeners can track. This suggests that speech is well-adapted to public communication in facilitating, not creating a barrier to, exchange of language forms.
Assuntos
Fonética , Percepção da Fala , Fala , HumanosRESUMO
A machine that can read printed material to the blind became a priority at the end of World War II with the appointment of a U.S. Government committee to instigate research on sensory aids to improve the lot of blinded veterans. The committee chose Haskins Laboratories to lead a multisite research program. Initially, Haskins researchers overestimated the capacities of users to learn an acoustic code based on the letters of a text, resulting in unsuitable designs. Progress was slow because the researchers clung to a mistaken view that speech is a sound alphabet and because of persisting gaps in man-machine technology. The tortuous route to a practical reading machine transformed the scientific understanding of speech perception and reading at Haskins Labs and elsewhere, leading to novel lines of basic research and new technologies. Research at Haskins Laboratories made valuable contributions in clarifying the physical basis of speech. Researchers recognized that coarticulatory overlap eliminated the possibility of alphabet-like discrete acoustic segments in speech. This work advanced the study of speech perception and contributed to our understanding of the relation of speech perception to production. Basic findings on speech enabled the development of speech synthesis, part science and part technology, essential for development of a reading machine, which has found many applications. Findings on the nature of speech further stimulated a new understanding of word recognition in reading across languages and scripts and contributed to our understanding of reading development and reading disabilities.
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Cegueira/reabilitação , Leitura , Auxiliares Sensoriais/história , Percepção da Fala/fisiologia , Desenho de Equipamento/história , História do Século XX , Humanos , Estados UnidosRESUMO
Here we identify approximately 40,000 healthy human volunteers who were intentionally exposed to infectious pathogens in clinical research studies dating from late World War II to the early 2000s. Microbial challenge experiments continue today under contemporary human subject research requirements. In fact, we estimated 4,000 additional volunteers who were experimentally infected between 2010 and the present day. We examine the risks and benefits of these experiments and present areas for improvement in protections of participants with respect to safety. These are the absence of maximum limits to risk and the potential for institutional review boards to include questionable benefits to subjects and society when weighing the risks and benefits of research protocols. The lack of a duty of medical care by physician-investigators to research subjects is likewise of concern. The transparency of microbial challenge experiments and the safety concerns raised in this work may stimulate further dialogue on the risks to participants of human experimentation.
Assuntos
Pesquisa Biomédica/ética , Voluntários Saudáveis , Infecções , Intenção , Projetos de Pesquisa , Sujeitos da Pesquisa , Segurança , Comitês de Ética em Pesquisa , Ética Médica , Ética em Pesquisa , Experimentação Humana/ética , Humanos , Consentimento Livre e Esclarecido , Pesquisadores/ética , Risco , Medição de RiscoRESUMO
Formaldehyde-fixed, paraffin-embedded (FFPE) tissue repositories represent a valuable resource for the retrospective study of disease progression and response to therapy. However, the proteomic analysis of FFPE tissues has been hampered by formaldehyde-induced protein modifications, which reduce protein extraction efficiency and may lead to protein misidentification. Here, we demonstrate the use of heat augmented with high hydrostatic pressure (40,000 psi) as a novel method for the recovery of intact proteins from FFPE tissue. Our laboratory has taken a mechanistic approach to developing improved protein extraction protocols, by first studying the reactions of formaldehyde with proteins and ways to reverse these reactions, then applying this approach to a model system called a "tissue surrogate", which is a gel formed by treating high concentrations of cytoplasmic proteins with formaldehyde, and finally FFPE mouse liver tissue. Our studies indicate that elevated pressure improves the recovery of proteins from FFPE tissue surrogates by hydrating and promoting solubilization of highly aggregated proteins allowing for the subsequent reversal (by hydrolysis) of formaldehyde-induced protein adducts and cross-links. When FFPE mouse liver was extracted using heat and elevated pressure, there was a 4-fold increase in protein extraction efficiency and up to a 30-fold increase in the number of non-redundant proteins identified by mass spectrometry, compared to matched tissue extracted with heat alone. More importantly, the number of non-redundant proteins identified in the FFPE tissue was nearly identical to that of the corresponding frozen tissue.
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Perception of a speech segment changes depending on properties of surrounding segments in a phenomenon called compensation for coarticulation (Mann, 1980). The nature of information that drives these perceptual changes is a matter of debate. One account attributes perceptual shifts to low-level auditory system contrast effects based on static portions of the signal (e.g., third formant [F3] center or average frequency; Lotto & Kluender, 1998). An alternative account is that listeners' perceptual shifts result from listeners attuning to the acoustic effects of gestural overlap and that this information for coarticulation is necessarily dynamic (Fowler, 2006). In a pair of experiments, we used sinewave speech precursors to investigate the nature of information for compensation for coarticulation. In Experiment 1, as expected by both accounts, we found that sinewave speech precursors produce shifts in following segments. In Experiment 2, we investigated whether effects in Experiment 1 were driven by static F3 offsets of sinewave speech precursors, or by dynamic relationships among their formants. We temporally reversed F1 and F2 in sinewave precursors, preserving static F3 offset and average F1, F2 and F3 frequencies, but disrupting dynamic formant relationships. Despite having identical F3s, selectively reversed precursors produced effects that were significantly smaller and restricted to only a small portion of the continuum. We conclude that dynamic formant relations rather than static properties of the precursor provide information for compensation for coarticulation.
Assuntos
Atenção , Gestos , Fonética , Espectrografia do Som , Acústica da Fala , Percepção da Fala , Feminino , Humanos , Masculino , Distorção da Percepção , Mascaramento Perceptivo , Percepção Visual , Qualidade da Voz , Adulto JovemRESUMO
Urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor type-1 (PAI-1) have been validated at the highest level of evidence as clinical biomarkers of prognosis in breast cancer. The American Society of Clinical Oncology recommends using uPA and PAI-1 levels in breast tumors for deciding whether patients with newly diagnosed node-negative breast cancer can forgo adjuvant chemotherapy. The sole validated method for quantifying uPA and PAI-1 levels in breast tumor tissue is a colorimetric ELISA assay that takes 3 days to complete and requires 100-300 mg of fresh or frozen tissue. In this study we describe a new assay method for quantifying PAI-1 levels in human breast tumor tissue. This assay combines pressure-cycling technology to extract PAI-1 from breast tumor tissue with a highly sensitive liposome polymerase chain reaction immunoassay for quantification of PAI-1 in the tissue extract. The new PAI-1 assay method reduced the total assay time to one day and improved assay sensitivity and dynamic range by >100, compared to ELISA.
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I discuss language forms as the primary means that language communities provide to enable public language use. As such, they are adapted to public use most notably in being linguistically significant vocal tract actions, not the categories in the mind as proposed in phonological theories. Their primary function is to serve as vehicles for production of syntactically structured sequences of words. However, more than that, phonological actions themselves do work in public language use. In particular, they foster interpersonal coordination in social activities. An intriguing property of language forms that likely reflects their emergence in social communicative activities is that phonological forms that should be meaningless (in order to serve their role in the openness of language at the level of the lexicon) are not wholly meaningless. In fact, the form-meaning "rift" is bridged bidirectionally: The smallest language forms are meaningful, and the meanings of lexical language forms generally inhere, in part, in their embodiment by understanders.
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This study examined the intelligibility of native and Mandarin-accented English speech for native English and native Mandarin listeners. In the latter group, it also examined the role of the language environment and English proficiency. Three groups of listeners were tested: native English listeners (NE), Mandarin-speaking Chinese listeners in the US (M-US) and Mandarin listeners in Beijing, China (M-BJ). As a group, M-US and M-BJ listeners were matched on English proficiency and age of acquisition. A nonword transcription task was used. Identification accuracy for word-final stops in the nonwords established two independent interlanguage intelligibility effects. An interlanguage speech intelligibility benefit for listeners (ISIB-L) was manifest by both groups of Mandarin listeners outperforming native English listeners in identification of Mandarin-accented speech. In the benefit for talkers (ISIB-T), only M-BJ listeners were more accurate identifying Mandarin-accented speech than native English speech. Thus, both Mandarin groups demonstrated an ISIB-L while only the M-BJ group overall demonstrated an ISIB-T. The English proficiency of listeners was found to modulate the magnitude of the ISIB-T in both groups. Regression analyses also suggested that the listener groups differ in their use of acoustic information to identify voicing in stop consonants.
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An elderly man with long-standing, nonresectable pheochromocytoma had rapid development of rectal adenocarcinoma despite close endoscopic surveillance. We determined that the patient's colorectal cancer overexpressed muscarinic receptor subtype 3, whereas his pheochromocytoma expressed choline acetyltransferase, an enzyme required to produce acetylcholine, which is a muscarinic receptor agonist. These findings suggested that acetylcholine release from the pheochromocytoma stimulated rapid growth of the rectal neoplasm. As proof of principle, we found that culture media conditioned by pheochromocytoma cells stimulates proliferation of a human colon cancer cell line, an effect attenuated by atropine, a muscarinic receptor inhibitor. Our observations provide both clinical and laboratory evidence that muscarinic receptor agonists promote the growth of colorectal neoplasia.
Assuntos
Acetilcolina/metabolismo , Neoplasias das Glândulas Suprarrenais/fisiopatologia , Colina O-Acetiltransferase/metabolismo , Neoplasias Colorretais/fisiopatologia , Feocromocitoma/fisiopatologia , Receptores Muscarínicos/fisiologia , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/metabolismo , Idoso , Neoplasias Colorretais/complicações , Humanos , Masculino , Feocromocitoma/complicações , Feocromocitoma/metabolismo , Reação em Cadeia da Polimerase , Receptores Muscarínicos/metabolismoRESUMO
Archival formalin-fixed, paraffin-embedded (FFPE) tissue and their associated diagnostic records represent an invaluable source of retrospective proteomic information on diseases for which the clinical outcome and response to treatment are known. However, analysis of archival FFPE tissues by high-throughput proteomic methods has been hindered by the adverse effects of formaldehyde fixation and subsequent tissue histology. This review examines recent methodological advances for extracting proteins from FFPE tissue suitable for proteomic analysis. These methods, based largely upon heat-induced antigen retrieval techniques borrowed from immunohistochemistry, allow at least a qualitative analysis of the proteome of FFPE archival tissues. The authors also discuss recent advances in the proteomic analysis of FFPE tissue; including liquid-chromatography tandem mass spectrometry, reverse phase protein microarrays and imaging mass spectrometry.
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Proteômica/métodos , Inclusão do Tecido/métodos , Fixação de Tecidos/métodos , Animais , Formaldeído , Humanos , Espectrometria de Massas/métodos , ParafinaRESUMO
Embedding theories of language production and comprehension in theories of action-perception is realistic and highlights that production and comprehension processes are interleaved. However, layers of internal models that repeatedly predict future linguistic actions and perceptions are implausible. I sketch an ecological alternative whereby perceiver/actors are modeled as dynamical systems coupled to one another and to the environment.
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Compreensão/fisiologia , Modelos Teóricos , Percepção da Fala/fisiologia , Fala/fisiologia , HumanosRESUMO
Tissue-based proteomic approaches (tissue proteomics) are essential for discovering and evaluating biomarkers for personalized medicine. In any proteomics study, the most critical issue is sample extraction and preparation. This problem is especially difficult when recovering proteins from formalin-fixed, paraffin-embedded (FFPE) tissue sections. However, improving and standardizing protein extraction from FFPE tissue is a critical need because of the millions of archival FFPE tissues available in tissue banks worldwide. Recent progress in the application of heat-induced antigen retrieval principles for protein extraction from FFPE tissue has resulted in a number of published FFPE tissue proteomics studies. However, there is currently no consensus on the optimal protocol for protein extraction from FFPE tissue or accepted standards for quantitative evaluation of the extracts. Standardization is critical to ensure the accurate evaluation of FFPE protein extracts by proteomic methods such as reverse phase protein arrays, which is now in clinical use. In our view, complete solubilization of FFPE tissue samples is the best way to achieve the goal of standardizing the recovery of proteins from FFPE tissues. However, further studies are recommended to develop standardized protein extraction methods to ensure quantitative and qualitative reproducibility in the recovery of proteins from FFPE tissues.
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Fixadores/química , Formaldeído/química , Inclusão em Parafina/métodos , Parafina/química , Proteoma/análise , Biomarcadores/análise , Humanos , Reprodutibilidade dos TestesRESUMO
Nonspeech materials are widely used to identify basic mechanisms underlying speech perception. For instance, they have been used to examine the origin of compensation for coarticulation, the observation that listeners' categorization of phonetic segments depends on neighboring segments (Mann, 1980). Specifically, nonspeech precursors matched to critical formant frequencies of speech precursors have been shown to produce similar categorization shifts as speech contexts. This observation has been interpreted to mean that spectrally contrastive frequency relations between neighboring segments underlie the categorization shifts observed after speech, as well as nonspeech precursors (Lotto & Kluender, 1998). From the gestural perspective, however, categorization shifts in speech contexts occur because of listeners' sensitivity to acoustic information for coarticulatory gestural overlap in production; in nonspeech contexts, this occurs because of energetic masking of acoustic information for gestures. In 2 experiments, we distinguish the energetic masking and spectral contrast accounts. In Experiment 1, we investigated the effects of varying precursor tone frequency on speech categorization. Consistent only with the masking account, tonal effects were greater for frequencies close enough to those in the target syllables for masking to occur. In Experiment 2, we filtered the target stimuli to simulate effects of masking and obtained behavioral outcomes that closely resemble those with nonspeech tones. We conclude that masking provides the more plausible account of nonspeech context effects. More generally, we suggest that similar results from the use of speech and nonspeech materials do not automatically imply identical origins and that the use of nonspeech in speech studies entails careful examination of the nature of information in the nonspeech materials.
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Percepção Auditiva/fisiologia , Mascaramento Perceptivo/fisiologia , Percepção da Fala/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Detecção de Sinal Psicológico/fisiologia , Adulto JovemRESUMO
Formaldehyde-fixed, paraffin-embedded (FFPE) tissue repositories represent a valuable resource for the retrospective study of disease progression and response to therapy. However, the proteomic analysis of FFPE tissues has been hampered by formaldehyde-induced protein modifications, which reduce protein extraction efficiency and may lead to protein misidentification. Here, we demonstrate the use of heat augmented with high hydrostatic pressure (40,000 psi) as a novel method for the recovery of intact proteins from FFPE mouse liver. When FFPE mouse liver was extracted using heat and elevated pressure, there was a 4-fold increase in protein extraction efficiency, a 3-fold increase in the extraction of intact proteins, and up to a 30-fold increase in the number of nonredundant proteins identified by mass spectrometry, compared to matched tissue extracted with heat alone. More importantly, the number of nonredundant proteins identified in the FFPE tissue was nearly identical to that of matched fresh-frozen tissue.
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Proteínas/isolamento & purificação , Proteoma/isolamento & purificação , Proteômica/métodos , Animais , Formaldeído , Temperatura Alta , Pressão Hidrostática , Fígado/química , Camundongos , Inclusão em Parafina , Proteínas/análise , Proteínas/química , Proteoma/análise , Proteoma/químicaRESUMO
This study examined fMRI activation when perceivers either passively observed or observed and imitated matched or mismatched audiovisual ("McGurk") speech stimuli. Greater activation was observed in the inferior frontal gyrus (IFG) overall for imitation than for perception of audiovisual speech and for imitation of the McGurk-type mismatched stimuli than matched audiovisual stimuli. This unique activation in the IFG during imitation of incongruent audiovisual speech may reflect activation associated with direct matching of incongruent auditory and visual stimuli or conflict between category responses. This study provides novel data about the underlying neurobiology of imitation and integration of AV speech.