Graphene Synthesis by Plasma-Enhanced CVD Growth with Ethanol

A modified route to synthesize graphene flakes is proposed using the Chemical Vapor Deposition (CVD) technique, by using copper substrates as supports. The carbon source used was ethanol, the synthesis temperature was 950°C and the pressure was controlled along the whole process. In this CVD synthesis process the incorporation of the carbon source was produced at low pressure and 950°C inducing the appearance of a plasma blue flash inside the quartz tube. Apparently, the presence of this plasma blue flash is required for obtaining graphene flakes. The synthesized graphene was characterized by different techniques, showing the presence of non-oxidized graphene with high purityThis work was supported by the Spanish Education and Research Ministry (MEC) under Grant MAT2010- 19804 and from Ministerio de Economía y Competitividad (MINECO) of Spain, through the grant ENE2014-57977-C2-1-R. Financial support from the U.S. Department of Energy, through the Massie Chair Project at Turabo University and from the U.S. Department of Defense under Grant W911NF-14-1- 0046, are also acknowledge

A Natural Near-Infrared Fluorescent Probe for Cancer Cell Imaging

Background: Rio Grande Valley (RGV) suffers from a high prevalence of certain cancers and lack the resources for accurate early diagnosis. Near-infrared (NIR) fluorescence-based imaging is a noteworthy and safer strategy for cancer detection compared to radiological imaging. There are several NIR dyes including indocyanine green (ICG) and its analogues that allow high-resolution and deep tissue imaging. However, these dyes possess some drawbacks, namely photo instability, toxicity, poor water solubility, and short half-lives. Chlorophyll (Chl) is a natural dietary and biocompatible NIR fluorescent substance which has the potential to serve as a cancer NIR imaging candidate. Hence, we aim to extract Chl from dietary leaves for cancer cell imaging. Methods: 12 different dietary leaves were imaged using the IVIS imaging system at 600/710 nm to assess the fluorescence distribution of chlorophyll. Next, Chl dye was extracted using ethanol from the 6 most fluorescent leaves and visualized for fluorescence. Size distribution, surface charge, and the concentration of these extracts were measured by a DLS system. Chl internalization in AsPC-1 (pancreatic) and SK-HEP-1 (liver) cancer cell lines was determined by EVOS imaging system after treated with highest fluorescent extract at different concentrations. Results: IVIS imaging data revealed that Chl was most fluorescent in bay leaf extract (4.98x1010 MFI). Physicochemical characterization of bay leaf extracted Chl indicated the particle size of 62.7 nm, zeta potential of -24.76 mV, and concentration at 1.11x1012 particles/mL. Cellular internalization data showed a dose dependent increase in bay leaf extracted Chl fluorescence in both cancer cell lines. Conclusions: This data suggests that dietary Chl is a potent biocompatible alternative for cancer cells NIR fluorescent imaging

A Natural Near-Infrared Fluorescent Probe for Cancer Cell Imaging

Introduction: Near-Infrared (NIR) fluorescence-based imaging is a noteworthy and safer strategy for cancer cells/tissues imaging compared to radiological imaging. NIR fluorescence offers deep tissue penetration and have minimal obstruction by autofluorescence and photon scattering [1]. There are several NIR dyes including indocyanine green (ICG) [2] and IR-1061 [3] that allow high-resolution tissue imaging. However, these dyes possess some low-quality characteristics which limit their use, namely photo instability, toxicity, poor water solubility, and short half-lives [4]. Therefore, more efficient and effective alternatives are urgently required to provide the desired clinical outcomes. Chlorophyll (Chl) is a natural dietary NIR fluorescence emitting substance which has the potential to serve as a lead NIR imaging candidate for cancer administration [5]. Objective: Developing a biocompatible NIR imaging dye from natural resources that can facilitate cancer cells/tissues imaging for improved detection. Chlorophyll is a natural NIR fluorescent alternative that is widely present in plants and green vegetables. Hence, we aim to extract Chl from dietary herbs and vegetables for cancer imaging. Methods: We selected 12 different leaves such as basil, bay leaf, collard, dill, kale, lettuce, mint, oregano, rosemary, sage, spinach, and thyme to assess the fluorescence distribution of chlorophyll. Each leaf was imaged in triplicates using the IVIS In Vivo Imaging System to detect Chl with excitation and emission wavelengths at 600/710 nm. Based on fluorescent intensity levels, next, we selected the 6 most fluorescent leaves (Bay leaf, collard, lettuce, mint, oregano, and spinach) and extracted the Chl dye using ethanol. The extracts were again visualized with IVIS system for Chl detection. Further, a Dynamic Light Scattering (DLS) system was used to measure size distribution, surface charge and the concentration of these Chl extracts. In order to determine the Chl internalization in cancer cells, AsPC-1 (pancreatic) and SK-HEP-1 (liver), two cell lines were treated with bay leaf (highest fluorescence) extracted Chl at different concentrations (10, 20, 30, 40 and 50 µg) for an hour and imaged under red channel using an EVOS Imaging System. Results: Whole leaf IVIS imaging revealed that spinach had the maximum Chl fluorescence of ~ 1.92x1012 and the lowest was in thyme ~ 8.60x1010. On the other hand, extracted Chl was most detectable in bay leaf extract (~ 4.98x1010). Additionally, physicochemical characterization of extracted Chl from these leaves suggested the particle size range of ~ 50 to 230 nm (Bay leaf 62.7 nm), zeta potential of ~ -20 to -25 (Bay leaf -24.76) and the obtained concentrations were, 1.11x1012 for bay leaf (Highest) and 5.01x109 for lettuce (Lowest). Moreover, cellular internalization data obtained using a fluorescent microscopy indicated a dose dependent increase in the bay leaf extracted Chl fluorescence in both cell lines. However, the fluorescence level was more prominent in the SK-HEP-1 cells compared to AsPC-1. Discussion: NIR fluorescent dyes play a significant role when it comes to the early stage cancer detection. Chlorophyll has NIR fluorescent excitation ~ 604 nm and emission ~ 700 nm which offers the capability of high-resolution imaging with deep tissue penetration, making it ideal for cancer imaging. Extraction process of Chl from dietary leaves is highly scalable and reproducible, herein, we have screened different leaves for Chl fluorescence, and it was evident that bay leaf exhibited the highest yield and Chl fluorescence. Conclusions: Taken together, our data suggested that Chl extracted from dietary resources, is a potent biocompatible alternative for NIR fluorescence which can be applied to cancer cells and tissues/tumors for enhanced detection resolution

Developing A Chlorophyll-Based Near-Infrared Fluorescent Probe for Cancer Cell Imaging

Introduction: Near-Infrared (NIR) fluorescence-based imaging is a noteworthy and safer strategy for cancer cells/tissues imaging compared to radiological imaging. NIR fluorescence offers deep tissue penetration and have minimal obstruction by autofluorescence and photon scattering [1]. There are several NIR dyes including indocyanine green (ICG) [2] and IR-1061 [3] that allow high-resolution tissue imaging. However, these dyes possess some low-quality characteristics which limit their use, namely photo instability, toxicity, poor water solubility, and short half-lives [4]. Therefore, more efficient and effective alternatives are urgently required to provide the desired clinical outcomes. Chlorophyll (Chl) is a natural dietary NIR fluorescence emitting substance which has the potential to serve as a lead NIR imaging candidate for cancer administration [5]. Objective: Developing a biocompatible NIR imaging dye from natural resources that can facilitate cancer cells/tissues imaging for improved detection. Chlorophyll is a natural NIR fluorescent alternative that is widely present in plants and green vegetables. Hence, we aim to extract Chl from dietary herbs and vegetables for cancer imaging. Methods: We selected 12 different leaves such as basil, bay leaf, collard, dill, kale, lettuce, mint, oregano, rosemary, sage, spinach, and thyme to assess the fluorescence distribution of chlorophyll. Each leaf was imaged in triplicates using the IVIS In Vivo Imaging System to detect Chl with excitation and emission wavelengths at 600/710 nm. Based on fluorescent intensity levels, next, we selected the 6 most fluorescent leaves (Bay leaf, collard, lettuce, mint, oregano, and spinach) and extracted the Chl dye using ethanol. The extracts were again visualized with IVIS system for Chl detection. Further, a Dynamic Light Scattering (DLS) system was used to measure size distribution, surface charge and the concentration of these Chl extracts. In order to determine the Chl internalization in cancer cells, AsPC-1 (pancreatic) and SK-HEP-1 (liver), two cell lines were treated with bay leaf (highest fluorescence) extracted Chl at different concentrations (10, 20, 30, 40 and 50 µg) for an hour and imaged under red channel using an EVOS Imaging System. Results: Whole leaf IVIS imaging revealed that spinach had the maximum Chl fluorescence of ~ 1.92x1012 and the lowest was in thyme ~ 8.60x1010. On the other hand, extracted Chl was most detectable in bay leaf extract (~ 4.98x1010). Additionally, physicochemical characterization of extracted Chl from these leaves suggested the particle size range of ~ 50 to 230 nm (Bay leaf 62.7 nm), zeta potential of ~ -20 to -25 (Bay leaf -24.76) and the obtained concentrations were, 1.11x1012 for bay leaf (Highest) and 5.01x109 for lettuce (Lowest). Moreover, cellular internalization data obtained using a fluorescent microscopy indicated a dose dependent increase in the bay leaf extracted Chl fluorescence in both cell lines. However, the fluorescence level was more prominent in the SK-HEP-1 cells compared to AsPC-1. Discussion: NIR fluorescent dyes play a significant role when it comes to the early stage cancer detection. Chlorophyll has NIR fluorescent excitation ~ 604 nm and emission ~ 700 nm which offers the capability of high-resolution imaging with deep tissue penetration, making it ideal for cancer imaging. Extraction process of Chl from dietary leaves is highly scalable and reproducible, herein, we have screened different leaves for Chl fluorescence, and it was evident that bay leaf exhibited the highest yield and Chl fluorescence. Conclusions: Taken together, our data suggested that Chl extracted from dietary resources, is a potent biocompatible alternative for NIR fluorescence which can be applied to cancer cells and tissues/tumors for enhanced detection resolution

Neurocognitive markers of passive suicidal ideation in late-life depression

Objectives: (1) To delineate whether cognitive flexibility and inhibitory ability are neurocognitive markers of passive suicidal ideation (PSI), an early stage of suicide risk in depression and (2) to determine whether PSI is associated with volumetric differences in regions of the prefrontal cortex (PFC) in middle-aged and older adults with depression. Design: Cross-sectional study. Setting: University medical school. Participants: Forty community-dwelling middle-aged and older adults with depression from a larger study of depression and anxiety (NIMH R01 MH091342-05 PI: O\u27Hara). Measurements: Psychiatric measures were assessed for the presence of a DSM-5 depressive disorder and PSI. A neurocognitive battery assessed cognitive flexibility, inhibitory ability, as well as other neurocognitive domains. Results: The PSI group (n = 18) performed significantly worse on cognitive flexibility and inhibitory ability, but not on other neurocognitive tasks, compared to the group without PSI (n = 22). The group with PSI had larger left mid-frontal gyri (MFG) than the no-PSI group. There was no association between cognitive flexibility/inhibitory ability and left MFG volume. Conclusions: Findings implicate a neurocognitive signature of PSI: poorer cognitive flexibility and poor inhibitory ability not better accounted for by other domains of cognitive dysfunction and not associated with volumetric differences in the left MFG. This suggests that there are two specific but independent risk factors of PSI in middle- and older-aged adults

Imprisonment and internment: Comparing penal facilities North and South

Recent references to the ‘warehouse prison’ in the United States and the prisión-depósito in Latin America seem to indicate that penal confinement in the western hemisphere has converged on a similar model. However, this article suggests otherwise. It contrasts penal facilities in North America and Latin America in terms of six interrelated aspects: regimentation; surveillance; isolation; supervision; accountability; and formalization. Quantitatively, control in North American penal facilities is assiduous (unceasing, persistent and intrusive), while in Latin America it is perfunctory (sporadic, indifferent and cursory). Qualitatively, North American penal facilities produce imprisonment (which enacts penal intervention through confinement), while in Latin America they produce internment (which enacts penal intervention through release). Closely entwined with this qualitative difference are distinct practices of judicial involvement in sentencing and penal supervision. Those practices, and the cultural and political factors that underpin them, represent an interesting starting point for the explanation of the contrasting nature of imprisonment and internment