Changing the Way We See Ourselves in the World: Critical Youth Participatory Action Research Investigating Intergenerational Trauma and Macro-Cultural Influences with Adolescent Girls

This study explores the social-ecological experience of human development in adolescent girls in attempts to better understand what young people may need. Five adolescent girls participated in a three-month long critical youth participatory action research study utilizing a photovoice method to investigate environmental messages that impact their identity. Specific themes of intergenerational trauma and macro-cultural influences were identified through a co-generated data analysis process, which contributed to a community action plan. The data generated with the co-researchers provided thematic information for the researcher to apply in a critical discussion exploring the influence of social power structures on families and youth. A Social-Ecological Model of Development in Young People was designed to illustrate the environmental influences that impact mental health in young people. Sociological multi-tiered interventions were also provided as recommendations to support de-pathologizing children and adolescents within the psychology and mental health counseling fields

DMD-based software-configurable spatially-offset Raman spectroscopy for spectral depth-profiling of optically turbid samples

Spectral depth-profiling of optically turbid samples is of high interest to a broad range of applications. We present a method for measuring spatially-offset Raman spectroscopy (SORS) over a range of length scales by incorporating a digital micro-mirror device (DMD) into a sample-conjugate plane in the detection optical path. The DMD can be arbitrarily programmed to collect/reject light at spatial positions in the 2D sample-conjugate plane, allowing spatially offset Raman measurements. We demonstrate several detection geometries, including annular and simultaneous multi-offset modalities, for both macro- and micro-SORS measurements, all on the same instrument. Compared to other SORS modalities, DMD-based SORS provides more flexibility with only minimal additional experimental complexity for subsurface Raman collection

Holographic optical trapping Raman micro-spectroscopy for non-invasive measurement and manipulation of live cells

We present a new approach for combining holographic optical tweezers with confocal Raman spectroscopy. Multiple laser foci, generated using a liquid-crystal spatial light modulator, are individually used for both optical trapping and excitation of spontaneous Raman spectroscopy from trapped objects. Raman scattering from each laser focus is spatially filtered using reflective apertures on a digital micro-mirror device, which can be reconfigured with flexible patterns at video rate. We discuss operation of the instrument, and performance and viability considerations for biological measurements. We then demonstrate the capability of the instrument for fast, flexible, and interactive manipulation with molecular measurement of interacting live cell systems

Effect of doping profile and the work function variation on performance of double-gate TFET

Abstract Tunnel Field Effect Transistor (TFET) can be considered as one of the promising transistors because it can switch ON and OFF at lower voltages than the operation voltage of the metal oxide semiconductor field effect transistor (MOSFET). This paper presents the effects of gate electrode work function and the doping profile terminating within and outside the drain on the ambipolar current, the ION/IOFF ratio, and the subthreshold swing. The results show that, Gaussian doping profile terminating within the drain is the most promising for on/off ratio. All the simulations and results have been performed and obtained with the help of ATLAS device simulator (Silvaco) and MATLAB

Integrated AFM-Raman for molecular characterization of peptide nano- and micro-tubes

This work is focused on exploring a unique integration of techniques, Raman micro-spectroscopy and atomic force microscopy (AFM), which when combined offer more than the sum of their respective parts. The non-invasive chemical specificity afforded by Raman spectroscopy, combined with the nanoscale-resolution topographic imaging of AFM offer much individually. The physics underlying the practical application of each technique is very general; Raman spectroscopy detects molecular vibrational shifts using light, and AFM uses a physical probe to interact with a surface to provide topographic (and mechanical) information. As a result, there are few restrictions to the possible samples that can be studied with these techniques, from semiconductors and geological crystals, through to simple organic chemical structures all the way to complex biological molecules and systems such as cells and tissue. In this work, a synthetic biomaterial composed of diphenylalanine (FF) peptide units which self-assemble into strong tubular structures is used as a sample of interest when exploring the different possibilities available from a combined Raman-AFM instrument. First, the combined system was set up in order to perform tip-enhanced Raman spectroscopy (TERS), a technique promising Raman spectroscopic imaging at the resolution of AFM imaging. A relatively young technique, TERS has huge potential in extending the reach of Raman spectroscopic imaging to the nanoscale, at a regime where a great deal of structure exists, but is usually blurred by conventional diffraction-limited Raman microspectroscopy. A major focus in this work is addressing a current problem with TERS: the fabrication of suitable probes. TERS typically utilizes AFM tips modified to have a silver nanoparticle, capable of locally enhancing the Raman signal, attached at the probe apex. A new method is presented here that promises several improvements over existing approaches, as the entire fabrication can be performed in-situ on the instrument. Tips produced in this way are then characterized by electron microscopy and tested on FF nanotubes. Following this, several techniques for the synthesis of silver nanoparticles are explored for use in TERS. Here, the focus is particularly on decahedral nanoparticles, which can be grown into rod shaped particles with well- defined shapes and sizes. These are important considerations for obtaining the desired enhancing properties for TERS probes. Finally, the AFM-Raman instrument is used to investigate the mechanical properties of FF tubes using several methods. AFM force spectroscopy of tubes suspended across a gap can be used in conjunction with a bending beam theory to measure the Young's modulus of individual tubes. A new type of co-localized experiment using polarized Raman spectroscopy on a suspended tube under various forces from the AFM is tested, and subsequently information relating to the hydrogen bonding network is used, in conjunction with existing X-ray data, to determine the molecular contributions to the modulus using a simple model for amyloid fibrils. Each experiment operates at the single fibril level, with the same fibrils being used, such that different methods can be compared for a single FF tube

Regional thalamic neuropathology in patients with hippocampal sclerosis and epilepsy: A postmortem study

Purpose Clinical, experimental, and neuroimaging data all indicate that the thalamus is involved in the network of changes associated with temporal lobe epilepsy (TLE), particularly in association with hippocampal sclerosis (HS), with potential roles in seizure initiation and propagation. Pathologic changes in the thalamus may be a result of an initial insult, ongoing seizures, or retrograde degeneration through reciprocal connections between thalamic and limbic regions. Our aim was to carry out a neuropathologic analysis of the thalamus in a postmortem (PM) epilepsy series, to assess the distribution, severity, and nature of pathologic changes and its association with HS. Methods Twenty-four epilepsy PM cases (age range 25-87 years) and eight controls (age range 38-85 years) were studied. HS was classified as unilateral (UHS, 11 cases), bilateral (BHS, 4 cases) or absent (No-HS, 9 cases). Samples from the left and right sides of the thalamus were stained with cresyl violet (CV), and for glial firbillary acidic protein (GFAP) and synaptophysin. Using image analysis, neuronal densities (NDs) or field fraction staining values (GFAP, synaptophysin) were measured in four thalamic nuclei: anteroventral nucleus (AV), lateral dorsal nucleus (LD), mediodorsal nucleus (MD), and ventrolateral nucleus (VL). The results were compared within and between cases. Key Findings The severity, nature, and distribution of thalamic pathology varied between cases. A pattern that emerged was a preferential involvement of the MD in UHS cases with a reduction in mean ND ipsilateral to the side of HS (p = 0.05). In UHS cases, greater field fraction values for GFAP and lower values for synaptophysin and ND were seen in the majority of cases in the MD ipsilateral to the side of sclerosis compared to other thalamic nuclei. In addition, differences in the mean ND between classical HS, atypical HS, and No-HS cases were noted in the ipsilateral MD (p < 0.05), with lower values observed in HS. Significance Our study demonstrates that stereotypical pathologic changes, as seen in HS, are not clearly defined in the thalamus. This may be partly explained by the heterogeneity of our PM study group. With quantitation, there is some evidence for preferential involvement of the MD, suggesting a potential role in TLE, which requires further investigation. © Wiley Periodicals, Inc. © 2013 The Authors. Epilepsia published by Wiley Periodicals, Inc. on behalf of the International League Against Epilepsy

Active efflux leads to heterogeneous dissipation of proton motive force by protonophores in bacteria

ABSTRACT Various toxic compounds disrupt bacterial physiology. While bacteria harbor defense mechanisms to mitigate the toxicity, these mechanisms are often coupled to the physiological state of the cells and become ineffective when the physiology is severely disrupted. Here, we characterized such feedback by exposing Escherichia coli to protonophores. Protonophores dissipate the proton motive force (PMF), a fundamental force that drives physiological functions. We found that E. coli cells responded to protonophores heterogeneously, resulting in bimodal distributions of cell growth, substrate transport, and motility. Furthermore, we showed that this heterogeneous response required active efflux systems. The analysis of underlying interactions indicated the heterogeneous response results from efflux-mediated positive feedback between PMF and protonophores’ action. Our studies have broad implications for bacterial adaptation to stress, including antibiotics. IMPORTANCE An electrochemical proton gradient across the cytoplasmic membrane, alternatively known as proton motive force, energizes vital cellular processes in bacteria, including ATP synthesis, nutrient uptake, and cell division. Therefore, a wide range of organisms produce the agents that collapse the proton motive force, protonophores, to gain a competitive advantage. Studies have shown that protonophores have significant effects on microbial competition, host-pathogen interaction, and antibiotic action and resistance. Furthermore, protonophores are extensively used in various laboratory studies to perturb bacterial physiology. Here, we have characterized cell growth, substrate transport, and motility of Escherichia coli cells exposed to protonophores. Our findings demonstrate heterogeneous effects of protonophores on cell physiology and the underlying mechanism

BCG-itis — case report, review of the literature

Gruźlica ciągle stanowi bardzo poważny światowy problem zdrowia publicznego. Leczeniegruźlicy jest trudne, gdyż wymaga długiego okresu stosowania ki lku leków przeciwprątkowych.Szczepionka Bacille Calmette- Guérin (BCG) chroni pr zed gruźlicą, gruźliczymzapalenie opon mózgowych i gruźlicą rozsianą. Chociaż szczepienie BCG jest uważane zabezpieczne, niekiedy mogą wystąpić niekorzystne objawy regionalne (BCG-itis) oraz rozsianezmiany (BCG-osis). Z reguły ma to związek z upośledzeniem odporności gospodarza.Zakażenie ludzkim wirusem niedoboru odporności (HIV) u dziecka (transmisja przez matkęna dziecko) prowadzi do upośledzenia komórkowej odpowiedzi immu nologicznej, którato sytuacja stanowi wielkie wyzwanie dotyczące powszechnego sto sowania szczepionkiBCG. Światowa Organizacja Zdrowia (WHO) zaleca, aby dzieci, któ re są zakażone HIV,nawet jeśli nie mają objawów, nie powinny zostać zaszczepione szczepionką BCG. W pracyprzedstawiono pacjenta z pojedynczą zmianą skórną powstałą w miejscu szczepienia BCG.Tuberculosis still remains a huge global health problem. Control of tuberculosis expansionis very difficult. It requires the long-term use of anti-mycobacterial drugs. The BacilleCalmette-Guérin (BCG) vaccination protects against tuberculosis-related meningitis and disseminatedtuberculosis. Although vaccination with BCG is considered safe, adverse regional(BCG-itis) and disseminated (BCG-osis) diseases preferentially occur in the immunocompromisedhost. The infection with human immunodeficiency virus (HIV) by mother-to-childtransmission leads to impaired cellular immune responses, a situation that poses a greatchallenge regarding the universal use of BCG vaccine. World Health Organization recommendsthat children who are known to be HIV -infected, even if asymptomatic, should nolonger be immunized with BCG. We report a patient with solitary skin lesion from the BCGinjection site

Integrated AFM-Raman for molecular characterization of peptide nano- and micro-tubes

This work is focused on exploring a unique integration of techniques, Raman micro-spectroscopy and atomic force microscopy (AFM), which when combined offer more than the sum of their respective parts. The non-invasive chemical specificity afforded by Raman spectroscopy, combined with the nanoscale-resolution topographic imaging of AFM offer much individually. The physics underlying the practical application of each technique is very general; Raman spectroscopy detects molecular vibrational shifts using light, and AFM uses a physical probe to interact with a surface to provide topographic (and mechanical) information. As a result, there are few restrictions to the possible samples that can be studied with these techniques, from semiconductors and geological crystals, through to simple organic chemical structures all the way to complex biological molecules and systems such as cells and tissue. In this work, a synthetic biomaterial composed of diphenylalanine (FF) peptide units which self-assemble into strong tubular structures is used as a sample of interest when exploring the different possibilities available from a combined Raman-AFM instrument. First, the combined system was set up in order to perform tip-enhanced Raman spectroscopy (TERS), a technique promising Raman spectroscopic imaging at the resolution of AFM imaging. A relatively young technique, TERS has huge potential in extending the reach of Raman spectroscopic imaging to the nanoscale, at a regime where a great deal of structure exists, but is usually blurred by conventional diffraction-limited Raman microspectroscopy. A major focus in this work is addressing a current problem with TERS: the fabrication of suitable probes. TERS typically utilizes AFM tips modified to have a silver nanoparticle, capable of locally enhancing the Raman signal, attached at the probe apex. A new method is presented here that promises several improvements over existing approaches, as the entire fabrication can be performed in-situ on the instrument. Tips produced in this way are then characterized by electron microscopy and tested on FF nanotubes. Following this, several techniques for the synthesis of silver nanoparticles are explored for use in TERS. Here, the focus is particularly on decahedral nanoparticles, which can be grown into rod shaped particles with well- defined shapes and sizes. These are important considerations for obtaining the desired enhancing properties for TERS probes. Finally, the AFM-Raman instrument is used to investigate the mechanical properties of FF tubes using several methods. AFM force spectroscopy of tubes suspended across a gap can be used in conjunction with a bending beam theory to measure the Young's modulus of individual tubes. A new type of co-localized experiment using polarized Raman spectroscopy on a suspended tube under various forces from the AFM is tested, and subsequently information relating to the hydrogen bonding network is used, in conjunction with existing X-ray data, to determine the molecular contributions to the modulus using a simple model for amyloid fibrils. Each experiment operates at the single fibril level, with the same fibrils being used, such that different methods can be compared for a single FF tube