Flexible delivery of Er:YAG radiation at 2.94 µm with negative curvature silica glass fibers:a new solution for minimally invasive surgical procedures

We present the delivery of high energy microsecond pulses through a hollow-core negative-curvature fiber at 2.94 µm. The energy densities delivered far exceed those required for biological tissue manipulation and are of the order of 2300 J/cm(2). Tissue ablation was demonstrated on hard and soft tissue in dry and aqueous conditions with no detrimental effects to the fiber or catastrophic damage to the end facets. The energy is guided in a well confined single mode allowing for a small and controllable focused spot delivered flexibly to the point of operation. Hence, a mechanically and chemically robust alternative to the existing Er:YAG delivery systems is proposed which paves the way for new routes for minimally invasive surgical laser procedures

Strategic Coalitions and Agenda-Setting in Fragmented Congresses: How the PRI Sets the Legislative Agenda in Mexico

This essay suggests a theory of strategic legislative agenda control. It argues that a single party can effectively set the agenda under majoritarian gatekeeping rules without obtaining majority or even plurality status. The agenda-setting party need not be the median party in the assembly nor supported by executive-led parliamentary coalitions. The Mexican Chamber of Deputies provides a case study of how majoritarian gatekeeping and political context establish the conditions necessary for one-party-led agenda-setting in a fragmented congress with or without enduring coalitions. The failure of opposition coalitions to roll the ‘Partido Revolucionario Institucional’ evinces that party's ability to set the agenda through strategic coalition formation since 2000. High levels of party unity combined with strategic positioning have allowed the PRI to do so. The strategic nature of the PRI's coalition-making is documented and analyzed in the context of its historically pragmatic approach to coalition-making. The argument is supported by roll-call data analysis, using WNOMINATE, WRice scores, and roll rates

Ethical Considerations for Conducting Cancer Medical Studies: The Tuskegee Study Aftermath

Recruitment of African-Americans, particularly men in clinical and prevention studies, has not been successful and retention is a major challenge. The paper examines the impact of the Tuskegee Study on research in the 21st century and its effect on recruitment of African-Americans into medical studies. A total of 6 focus groups were conducted among male participants diagnosed with prostate cancer to elicit responses regarding factors influencing participation into prospective studies and trials. Sessions were transcribed and analyzed using content analysis. Echoes of the Tuskegee Public Health Study legacy was a major concern voiced by participants throughout the focus group process. Participants recognize the importance and benefit of research, however the potential for unethical practices continue to linger in the minds of participants. Attitudes and beliefs toward research and the stigma associated with the Tuskegee Public Health Study must also be addressed to increase enrollment of African-Americans in medical studies

Ret function in muscle stem cells points to tyrosine kinase inhibitor therapy for facioscapulohumeral muscular dystrophy

Facioscapulohumeral muscular dystrophy (FSHD) involves sporadic expression of DUX4, which inhibits myogenesis and is pro-apoptotic. To identify target genes, we over-expressed DUX4 in myoblasts and found that the receptor tyrosine kinase Ret was significantly up-regulated, suggesting a role in FSHD. RET is dynamically expressed during myogenic progression in mouse and human myoblasts. Constitutive expression of either RET9 or RET51 increased myoblast proliferation, whereas siRNA-mediated knockdown of Ret induced myogenic differentiation. Suppressing RET activity using Sunitinib, a clinically- approved tyrosine kinase inhibitor, rescued differentiation in both DUX4-expressing murine myoblasts and in FSHD patient-derived myoblasts. Importantly, Sunitinib also increased engraftment and differentiation of FSHD myoblasts in regenerating mouse muscle. Thus, DUX4-mediated activation of Ret prevents myogenic differentiation and could contribute to FSHD pathology by preventing satellite cell-mediated repair. Rescue of DUX4-induced pathology by Sunitinib highlights the therapeutic potential of tyrosine kinase inhibitors for treatment of FSHD

Working memory replay prioritizes weakly attended events

One view of working memory posits that maintaining a series of events requires their sequential and equal mnemonic replay. Another view is that the content of working memory maintenance is prioritized by attention. We decoded the dynamics for retaining a sequence of items using magnetoencephalography, wherein participants encoded sequences of three stimuli depicting a face, a manufactured object, or a natural item and maintained them in working memory for 5000 ms. Memory for sequence position and stimulus details were probed at the end of the maintenance period. Decoding of brain activity revealed that one of the three stimuli dominated maintenance independent of its sequence position or category; and memory was enhanced for the selectively replayed stimulus. Analysis of event-related responses during the encoding of the sequence showed that the selectively replayed stimuli were determined by the degree of attention at encoding. The selectively replayed stimuli had the weakest initial encoding indexed by weaker visual attention signals at encoding. These findings do not rule out sequential mnemonic replay but reveal that attention influences the content of working memory maintenance by prioritizing replay of weakly encoded events. We propose that the prioritization of weakly encoded stimuli protects them from interference during the maintenance period, whereas the more strongly encoded stimuli can be retrieved from long-term memory at the end of the delay period

Towards Neutrino Mass from Cosmology without Optical Depth Information

With low redshift probes reaching unprecedented precision, uncertainty of the CMB optical depth is expected to be the limiting factor for future cosmological neutrino mass constraints. In this paper, we discuss to what extent combinations of CMB lensing and galaxy surveys measurements at low redshifts $z\sim 0.5-5$ will be able to make competitive neutrino mass measurements without relying on any optical depth constraints. We find that the combination of LSST galaxies and CMB-S4 lensing should be able to achieve constraints on the neutrino mass sum of 25meV without optical depth information, an independent measurement that is competitive with or slightly better than the constraint of 30meV possible with CMB-S4 and present-day optical depth measurements. These constraints originate both in structure growth probed by cross-correlation tomography over a wide redshift range as well as, most importantly, the shape of the galaxy power spectrum measured over a large volume. We caution that possible complications such as higher-order biasing and systematic errors in the analysis of high redshift galaxy clustering are only briefly discussed and may be non-negligible. Nevertheless, our results show that new kinds of high-precision neutrino mass measurements at and beyond the present-day optical depth limit may be possible.Comment: 8 pages, 6 figure

Frequency of neurolopsychological deficits after traumatic brain injury

El traumatismo craneoencefálico (TCE) puede conllevar impactantes cambios en la vida cotidiana, que incluyen alteraciones a nivel social, profesional, comunicativo y cognitivo (dificultades atencionales, mnemónicas y ejecutivas). Este estudio tuvo por objeto caracterizar la ocurrencia de déficits neuropsicológicos post-TCE y constatar el impacto ocasionado por el nivel de severidad del trauma en el desempeño cognitivo de los pacientes. Participaron 96 adultos en la muestra total, que fue dividida en dos grupos para evaluar el nivel de severidad del trauma: TCE leve (n=39) y TCE grave (n=77). La gravedad de la lesión se clasificó por medio de la Escala de Coma de Glasgow, por la duración de la pérdida de consciencia, o por la amnesia post-traumática. No había diferencias entre la edad y la escolaridad de los participantes. Para la comparación entre los grupos en cuanto a la distribución de ocurrencia de déficits neuropsicológicos, se utilizó el Chi-cuadrado. Se utilizó una batería de evaluación neuropsicológica flexible conformada por tareas verbales y visoespaciales de habilidades lingüísticas, mnemónicas y ejecutivas. Los grupos no se diferenciaron en cuanto a las variables sociodemográficas. Los pacientes con TCE leve tuvieron mejores puntajes comparados con los de TCE grave (número de errores y categorías completadas del Test de clasificación de tarjetas de Wisconsin- [WCST, por sus siglas en inglés]; errores en la parte B del Test de Hayling; y en la interferencia retro y proactiva del Test de aprendizaje auditivo verbal de Rey [RAVLT, por sus siglas en inglés]. El nivel de severidad del trauma parece mostrar diferencias en los individuos en cuanto al desempeño en memoria episódica de información nueva y en el control de interferencia entre los recuerdos; lo mismo se aplica a las funciones de flexibilidad e inhibición. Estos resultados sugieren que es necesaria una mayor inversión en acciones de políticas públicas, priorizando intervenciones neurocognitivas reeducativas y métodos de prevención de accidentes relacionados con lesiones traumáticas que tengan alta incidencia de secuelas.El traumatismo craneoencefálico (TCE) puede conllevar impactantes cambios en la vida cotidiana, que incluyen alteraciones a nivel social, profesional, comunicativo y cognitivo (dificultades atencionales, mnemónicas y ejecutivas). Este estudio tuvo por objeto caracterizar la ocurrencia de déficits neuropsicológicos post-TCE y constatar el impacto ocasionado por el nivel de severidad del trauma en el desempeño cognitivo de los pacientes. Participaron 96 adultos en la muestra total, que fue dividida en dos grupos para evaluar el nivel de severidad del trauma: TCE leve (n=39) y TCE grave (n=77). La gravedad de la lesión se clasificó por medio de la Escala de Coma de Glasgow, por la duración de la pérdida de consciencia, o por la amnesia post-traumática. No había diferencias entre la edad y la escolaridad de los participantes. Para la comparación entre los grupos en cuanto a la distribución de ocurrencia de déficits neuropsicológicos, se utilizó el Chi-cuadrado. Se utilizó una batería de evaluación neuropsicológica flexible conformada por tareas verbales y visoespaciales de habilidades lingüísticas, mnemónicas y ejecutivas. Los grupos no se diferenciaron en cuanto a las variables sociodemográficas. Los pacientes con TCE leve tuvieron mejores puntajes comparados con los de TCE grave (número de errores y categorías completadas del Test de clasificación de tarjetas de Wisconsin- [WCST, por sus siglas en inglés]; errores en la parte B del Test de Hayling; y en la interferencia retro y proactiva del Test de aprendizaje auditivo verbal de Rey [RAVLT, por sus siglas en inglés]. El nivel de severidad del trauma parece mostrar diferencias en los individuos en cuanto al desempeño en memoria episódica de información nueva y en el control de interferencia entre los recuerdos; lo mismo se aplica a las funciones de flexibilidad e inhibición. Estos resultados sugieren que es necesaria una mayor inversión en acciones de políticas públicas, priorizando intervenciones neurocognitivas reeducativas y métodos de prevención de accidentes relacionados con lesiones traumáticas que tengan alta incidencia de secuelas.Traumatic brain injury (TBI) can lead to significant changes in daily life, as well as in social, labor, communicative, and cognitive domains (attention, memory and executive functions). This study aimed to characterize the occurrence of post-TBI neuropsychological deficits as well as to determine whether there is an impact related to the level of severity of the trauma on the patient's performance. Ninety-six adults participated in the study, who were divided in two groups to assess the trauma's level of severity: mild TBI (n=39) and severe TBI (n=57). This severity was classified by the Glasgow Coma Scale, by the duration of consciousness loss, or by post-traumatic amnesia. There were no differences between the groups regarding variables of age and years of schooling. A Chi- square test was used to do a comparison between the two groups in terms of occurrence of neuropsychological deficits. Verbal, visuospatial, mnemonic, linguistic and executive tests composed a flexible neuropsychological battery. Patients with mild TBI had better scores compared to those with severe TBI (number of errors and in completed categories of the Modified Wisconsin Card Sorting Test (MWCST); errors in Part B of The Hayling Test; and proactive and retroactive interference in the Rey Auditory Verbal Learning Test (RAVLT). The severity of the trauma seems to differentiate individual's performance on episodic memory of new information and in the control of interference between memories; the same is applied to flexibility and inhibition functions. These results suggest the need for more investments in public health policy actions, prioritizing neurocognitive remedial intervention and prevention methods for such condition with high incidence of sequelae

“Maybe I’m just not good enough?”: British swimmers’ experiences of attempting to qualify for the Olympic Games

The purpose of this study was to explore the transitional experiences of British swimmers as they attempted to qualify for the Olympic Games and gain a place in the British Swimming World Class Performance Programme. An Interpretive Phenomenological Analysis (IPA) approach was adopted.1 Six swimmers (aged 20-25 years), one of each of their parents, and four coaches completed interviews leading up to and following Olympic trials over an eight month period. Audio recordings were transcribed verbatim and analysed following the guidelines set out by Smith and Osborne. 2 Results indicated that athletes’ transition experiences were characterised by a range of demands, which were categorised into five higher order themes (a) Questioning “Am I good enough?”; (b) Managing and fulfilling expectations; (c) Operating within an environment that is working against them; (d) Lacking support and understanding of self and demands; and (e) Maintaining balance versus being an international swimmer. Overall, the results indicate that this attempted transition is complex, challenging, and unique and largely influenced by self-confidence. Addressing the individual factors impacting on athletes’ self-confidence appears critical to enhancing swimmers’ transitional experiences at the highest level

Gut microbiome composition in the Hispanic Community Health Study/Study of Latinos is shaped by geographic relocation, environmental factors, and obesity.

Background: Hispanics living in the USA may have unrecognized potential birthplace and lifestyle influences on the gut microbiome. We report a cross-sectional analysis of 1674 participants from four centers of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), aged 18 to 74 years old at recruitment.Results: Amplicon sequencing of 16S rRNA gene V4 and fungal ITS1 fragments from self-collected stool samples indicate that the host microbiome is determined by sociodemographic and migration-related variables. Those who relocate from Latin America to the USA at an early age have reductions in Prevotella to Bacteroides ratios that persist across the life course. Shannon index of alpha diversity in fungi and bacteria is low in those who relocate to the USA in early life. In contrast, those who relocate to the USA during adulthood, over 45 years old, have high bacterial and fungal diversity and high Prevotella to Bacteroides ratios, compared to USA-born and childhood arrivals. Low bacterial diversity is associated in turn with obesity. Contrasting with prior studies, our study of the Latino population shows increasing Prevotella to Bacteroides ratio with greater obesity. Taxa within Acidaminococcus, Megasphaera, Ruminococcaceae, Coriobacteriaceae, Clostridiales, Christensenellaceae, YS2 (Cyanobacteria), and Victivallaceae are significantly associated with both obesity and earlier exposure to the USA, while Oscillospira and Anaerotruncus show paradoxical associations with both obesity and late-life introduction to the USA.Conclusions: Our analysis of the gut microbiome of Latinos demonstrates unique features that might be responsible for health disparities affecting Hispanics living in the USA