Borough of Manhattan Community College

We present imaging data and photometry for the COSMOS survey in 15 photometric bands between 0.3 and 2.4 mum. These include data taken on the Subaru 8.3 m telescope, the KPNO and CTIO 4 m telescopes, and the CFHT 3.6 m telescope. Special techniques are used to ensure that the relative photometric calibration is better than 1% across the field of view. The absolute photometric accuracy from standard-star measurements is found to be 6%. The absolute calibration is corrected using galaxy spectra, providing colors accurate to 2% or better. Stellar and galaxy colors and counts agree well with the expected values. Finally, as the first step in the scientific analysis of these data we construct panchromatic number counts which confirm that both the geometry of the universe and the galaxy population are evolving. Based in part on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS5-26555 the Subaru telescope, which is operated by the National Astronomical Observatory of Japan; the MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA at the Canada-France-Hawaii Telescope, which is operated by the National Research Council of Canada, the Institute National des Science de l'Univers of the Centre National de la Recherche, and the University of Hawaii; and the Kitt Peak National Observatory, Cerro Tololo Inter-American Observatory, and the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation.

The Laser Interferometer Space Antenna (LISA) will be a transformative experiment for gravitational wave astronomy, and, as such, it will offer unique opportunities to address many key astrophysical questions in a completely novel way. The synergy with ground-based and space-born instruments in the electromagnetic domain, by enabling multi-messenger observations, will add further to the discovery potential of LISA. The next decade is crucial to prepare the astrophysical community for LISA's first observations. This review outlines the extensive landscape of astrophysical theory, numerical simulations, and astronomical observations that are instrumental for modeling and interpreting the upcoming LISA datastream. To this aim, the current knowledge in three main source classes for LISA is reviewed; ultra-compact stellar-mass binaries, massive black hole binaries, and extreme or interme-diate mass ratio inspirals. The relevant astrophysical processes and the established modeling techniques are summarized. Likewise, open issues and gaps in our understanding of these sources are highlighted, along with an indication of how LISA could help making progress in the different areas. New research avenues that LISA itself, or its joint exploitation with upcoming studies in the electromagnetic domain, will enable, are also illustrated. Improvements in modeling and analysis approaches, such as the combination of numerical simulations and modern data science techniques, are discussed. This review is intended to be a starting point for using LISA as a new discovery tool for understanding our Universe.

AIMS: Microglia are involved in neurodegeneration, are prime targets for anti-inflammatory therapy and are potential biomarkers of disease progression. For example, positron emission tomography imaging employing radioligands for the mitochondrial translocator protein of 18 kDa (TSPO, formerly known as the peripheral benzodiazepine receptor) is being scrutinized to detect neuroinflammation in various diseases. TSPO is presumably present in activated microglia, but may be present in other neural cells. METHODS: We sought to elucidate the protein expression in normal human central nervous system, several neurological diseases (HIV encephalitis, Alzheimer's disease, multiple sclerosis and stroke) and simian immunodeficiency virus encephalitis by performing immunohistochemistry with two anti-TSPO antibodies. RESULTS: Although the overall parenchymal staining was minimal in normal brain, endothelial and smooth muscle cells, subpial glia, intravascular monocytes and ependymal cells were TSPO-positive. In disease states, elevated TSPO was present in parenchymal microglia, macrophages and some hypertrophic astrocytes, but the distribution of TSPO varied depending on the disease, disease stage and proximity to the lesion or relation to infection. Staining with the two antibodies correlated well in white matter, but one antibody also stained cortical neurones. Quantitative analysis demonstrated a significant increase in TSPO in the white matter of HIV encephalitis compared with brains without encephalitis. TSPO expression was also increased in simian immunodeficiency virus encephalitis. CONCLUSIONS: This report provides the first comprehensive immunohistochemical analysis of the expression of TSPO. The results are useful for informing the usage of positron emission tomography as an imaging modality and have an impact on the potential use of TSPO as an anti-inflammatory pharmacological target.

Light-by-light scattering (γγ → γγ) is a quantum-mechanical process that is forbidden in the classical theory of electrodynamics. This reaction is accessible at the Large Hadron Collider thanks to the large electromagnetic field strengths generated by ultra-relativistic colliding lead ions. Using 480 μb−1 of lead–lead collision data recorded at a centre-of-mass energy per nucleon pair of 5.02 TeV by the ATLAS detector, here we report evidence for light-by-light scattering. A total of 13 candidate events were observed with an expected background of 2.6 ± 0.7 events. After background subtraction and analysis corrections, the fiducial cross-section of the process Pb + Pb (γγ) → Pb(∗) + Pb(∗)γγ, for photon transverse energy ET > 3 GeV, photon absolute pseudorapidity |η| < 2.4, diphoton invariant mass greater than 6 GeV, diphoton transverse momentum lower than 2 GeV and diphoton acoplanarity below 0.01, is measured to be 70 ± 24 (stat.) ± 17 (syst.) nb, which is in agreement with the standard model predictions. Quantum electrodynamics predicts a rare process in which light is scattered by light. The ATLAS Collaboration reports signs of this elusive effect in the collisions of ultra-relativistic lead ions.

The origins of the stellar-mass black hole mergers discovered by LIGO/Virgo are still unknown. Here we show that if migration traps develop in the accretion disks of active galactic nuclei (AGNs) and promote the mergers of their captive black holes, the majority of black holes within disks will undergo hierarchical mergers-with one of the black holes being the remnant of a previous merger. 40% of AGN-assisted mergers detected by LIGO/Virgo will include a black hole with mass ≳50M_{⊙}, the mass limit from stellar core collapse. Hierarchical mergers at traps in AGNs will exhibit black hole spins (anti)aligned with the binary's orbital axis, a distinct property from other hierarchical channels. Our results suggest, although not definitively (with odds ratio of ∼1), that LIGO's heaviest merger so far, GW170729, could have originated from this channel.

We previously showed that prostatic stem cells are concentrated in the proximal regions of prostatic ducts. We now report that these stem cells can be purified from isolated proximal duct regions by virtue of their high expression of the cell surface protein stem cell antigen 1 (Sca-1). In an in vivo prostate reconstitution assay, the purified Sca-1-expressing cell population isolated from the proximal region of ducts was more effective in generating prostatic tissue than a comparable population of Sca-1-depleted cells (203.0 +/- 83.1 mg vs. 11.9 +/- 9.2 mg) or a population of Sca-1-expressing cells isolated from the remaining regions of ducts (transit-amplifying cells) (31.9 +/- 24.1 mg). Almost all of the proliferative capacity of the proximal duct Sca-1-expressing cell population resides within the fraction of cells that express high levels of Sca-1 (top one-third), with the proximal region of prostatic ducts containing 7.2-fold more Sca-1(high) cells than the remaining regions. More than 60% of the high-expressing cells coexpress alpha6 integrin and the anti-apoptotic factor Bcl-2, markers that are also characteristic of stem cells of other origins. Further stratification of the phenotype of the stem cells may enable the development of rational therapies for treating prostate cancer and benign prostatic hyperplasia.

ABSTRACT Accretion disks around supermassive black holes (SMBHs) in active galactic nuclei (AGNs) contain stars, stellar mass black holes, and other stellar remnants, which perturb the disk gas gravitationally. The resulting density perturbations exert torques on the embedded masses causing them to migrate through the disk in a manner analogous to planets in protoplanetary disks. We determine the strength and direction of these torques using an empirical analytic description dependent on local disk gradients, applied to two different analytic, steady-state disk models of SMBH accretion disks. We find that there are radii in such disks where the gas torque changes sign, trapping migrating objects. Our analysis shows that major migration traps generally occur where the disk surface density gradient changes sign from positive to negative, around 20–300 R g , where R g = 2 GM / c 2 is the Schwarzschild radius. At these traps, massive objects in the AGN disk can accumulate, collide, scatter, and accrete. Intermediate mass black hole formation is likely in these disk locations, which may lead to preferential gap and cavity creation at these radii. Our model thus has significant implications for SMBH growth as well as gravitational wave source populations.

We present the results of a uniform analysis of the soft X-ray spectra of fifteen type I AGN observed with the high resolution X-ray gratings on board \emph{Chandra}. We found that ten of the fifteen AGN exhibit signatures of an intrinsic ionized absorber. The absorbers are photoionized and outflowing, with velocities in the range $\sim 10^{1}-10^{3}$ km $\rm{s}^{-1}$. The column density of the warm absorbing gas is $\sim 10^{20-23} \rm{cm}^{-2}$. Nine of the ten AGN exhibiting warm absorption are best--fit by multiple ionization components and three of the ten AGN \emph{require} multiple kinematic components. The warm absorbing gas in our AGN sample has a wide range of ionization parameter, spanning roughly four orders of magnitude ($\xi \sim 10^{0-4}$ ergs cm $\rm{s}^{-1}$) in total, and often spanning three orders of magnitude in the same gas. Warm absorber components with ionization parameter $\xi<10$ generate an unresolved transition array due to Fe in seven of the ten AGN exhibiting warm absorption. These low ionization state absorbers may also carry away the largest mass outflows from the AGN. The mass outflow rate depends critically on the volume filling factor of the gas, which cannot yet be directly measured. However, upper limits on the mass outflow ratesfor filling factors of unity can be much greater than the expected accretion rate onto the central supermassive black hole and filling factors as small as 1% can give outflow rates comparable to the accretion rate. There appears to be a gap in the outflow velocities in our sample between $\sim 300-500$ km $\rm{s}^{-1}$, the origin of which is not clear. The outflow components with velocities below this gap tend to be associated with lower column densities than those with velocities above the gap.

Abstract The merger rate of stellar-mass black hole binaries (sBHBs) inferred by the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) suggests the need for an efficient source of sBHB formation. Active galactic nucleus (AGN) disks are a promising location for the formation of these sBHBs, as well as binaries of other compact objects, because of powerful torques exerted by the gas disk. These gas torques cause orbiting compact objects to migrate toward regions in the disk where inward and outward torques cancel, known as migration traps. We simulate the migration of stellar mass black holes in an example of a model AGN disk, using an augmented N -body code that includes analytic approximations to migration torques, stochastic gravitational forces exerted by turbulent density fluctuations in the disk, and inclination and eccentricity dampening produced by passages through the gas disk, in addition to the standard gravitational forces between objects. We find that sBHBs form rapidly in our model disk as stellar-mass black holes migrate toward the migration trap. These sBHBs are likely to subsequently merge on short timescales. The process continues, leading to the build-up of a population of over-massive stellar-mass black holes. The formation of sBHBs in AGN disks could contribute significantly to the sBHB merger rate inferred by LIGO.

If intermediate-mass black holes (IMBHs) grow efficiently in gas discs around supermassive black holes, their host active galactic nucleus (AGN) discs should exhibit myriad observational signatures. Gap-opening IMBHs in AGN discs can exhibit spectral features and variability analogous to gapped protoplanetary discs. A gap-opening IMBH in the innermost disc imprints ripples and oscillations on the broad Fe K line which may be detectable with future X-ray missions. A non-gap-opening IMBH will accrete and produce a soft X-ray excess relative to continuum emission. An IMBH on a retrograde orbit in an AGN disc will not open a gap and will generate soft X-rays from a bow-shock 'headwind'. Accreting IMBH in a large cavity can generate ULX-like X-ray luminosities and LINER-like optical line ratios from local ionized gas. We propose that many LINERs house a weakly accreting MBH binary in a large central disc cavity and will be luminous sources of gravitational waves (GW). IMBHs in galactic nuclei may also be detected via intermittent observational signatures including: UV/X-ray flares due to tidal disruption events, asymmetric X-ray intensity distributions as revealed by AGN transits, quasi-periodic oscillations and underluminous Type Ia supernovae. GW emitted during IMBH inspiral and collisions may be detected with eLISA and LIGO, particularly from LINERs. We summarize observational signatures and compare to current data where possible or suggest future observations.

We assess the contribution of dynamical hardening by direct three-body scattering interactions to the rate of stellar-mass black hole binary (BHB) mergers in galactic nuclei. We derive an analytic model for the single-binary encounter rate in a nucleus with spherical and disc components hosting a super-massive black hole (SMBH). We determine the total number of encounters N GW needed to harden a BHB to the point that inspiral due to gravitational wave emission occurs before the next three-body scattering event. This is done independently for both the spherical and disc components. Using a Monte Carlo approach, we refine our calculations for N GW to include gravitational wave emission between scattering events. For astrophysically plausible models, we find that typically N GW 10. We find two separate regimes for the efficient dynamical hardening of BHBs: (1) spherical star clusters with high central densities, low-velocity dispersions, and no significant Keplerian component and (2) migration traps in discs around SMBHs lacking any significant spherical stellar component in the vicinity of the migration trap, which is expected due to effective orbital inclination reduction of any spherical population by the disc. We also find a weak correlation between the ratio of the second-order velocity moment to velocity dispersion in galactic nuclei and the rate of BHB mergers, where this ratio is a proxy for the ratio between the rotation-and dispersion-supported components. Because discs enforce planar interactions that are efficient in hardening BHBs, particularly in migration traps, they have high merger rates that can contribute significantly to the rate of BHB mergers detected by the advanced Laser Interferometer Gravitational-Wave Observatory.

Abstract We report a new changing-look quasar, WISE J105203.55+151929.5 at z = 0.303, found by identifying highly mid-IR-variable quasars in the Wide-field Infrared Survey Explorer ( WISE )/Near-Earth Object WISE Reactivation (NEOWISE) data stream. Compared to multiepoch mid-IR photometry of a large sample of SDSS-confirmed quasars, WISE J1052+1519 is an extreme photometric outlier, fading by more than a factor of two at 3.4 and 4.6 μ m since 2009. Swift target-of-opportunity observations in 2017 show even stronger fading in the soft X-rays compared to the ROSAT detection of this source in 1995, with at least a factor of 15 decrease. We obtained second-epoch spectroscopy with the Palomar telescope in 2017 that, when compared with the 2006 archival SDSS spectrum, reveals that the broad H β emission has vanished and that the quasar has become significantly redder. The two most likely interpretations for this dramatic change are source fading or obscuration, where the latter is strongly disfavored by the mid-IR data. We discuss various physical scenarios that could cause such changes in the quasar luminosity over this timescale, and favor changes in the innermost regions of the accretion disk that occur on the thermal and heating/cooling front timescales. We discuss possible physical triggers that could cause these changes, and predict the multiwavelength signatures that could distinguish these physical scenarios.

The resonance Raman (RR) spectra of six types of human brain tissues are examined using a confocal micro-Raman system with 532-nm excitation in vitro. Forty-three RR spectra from seven subjects are investigated. The spectral peaks from malignant meningioma, stage III (cancer), benign meningioma (benign), normal meningeal tissues (normal), glioblastoma multiforme grade IV (cancer), acoustic neuroma (benign), and pituitary adenoma (benign) are analyzed. Using a 532-nm excitation, the resonance-enhanced peak at 1548 cm-1 (amide II) is observed in all of the tissue specimens, but is not observed in the spectra collected using the nonresonance Raman system. An increase in the intensity ratio of 1587 to 1605 cm-1 is observed in the RR spectra collected from meningeal cancer tissue as compared with the spectra collected from the benign and normal meningeal tissue. The peak around 1732 cm-1 attributed to fatty acids (lipids) are diminished in the spectra collected from the meningeal cancer tumors as compared with the spectra from normal and benign tissues. The characteristic band of spectral peaks observed between 2800 and 3100 cm-1 are attributed to the vibrations of methyl (─CH3) and methylene (─CH2─) groups. The ratio of the intensities of the spectral peaks of 2935 to 2880 cm-1 from the meningeal cancer tissues is found to be lower in comparison with that of the spectral peaks from normal, and benign tissues, which may be used as a distinct marker for distinguishing cancerous tissues from normal meningeal tissues. The statistical methods of principal component analysis and the support vector machine are used to analyze the RR spectral data collected from meningeal tissues, yielding a diagnostic sensitivity of 90.9% and specificity of 100% when two principal components are used.

Abstract Accretion disks around supermassive black holes (SMBHs) are promising sites for stellar mass black hole (BH) mergers due to mass segregation and merger acceleration by disk gas torques. Here we show that a gravitational-wave (GW) kick at BH merger causes ram-pressure stripping of gas within the BH Hill sphere. If R H ≥ H , the disk height, an off-center UV flare at a BH ∼ 10 3 r g , emerges within t UV ∼ O(2 days)( a BH /10 3 r g )( M SMBH /10 8 M ⊙ )( v kick /10 2 km s −1 ) postmerger and lasts O( R H / v kick ) ∼ O(5 t UV ). The flare emerges with luminosity O(10 42 erg s −1 )( t UV /2days) −1 ( M Hill /1 M ⊙ )( v kick /10 2 km s −1 ) 2 . Active galactic nucleus optical/UV photometry is altered and asymmetric broad emission line profiles can develop after weeks. If R H &lt; H , detectability depends on disk optical depth. Follow-up by large optical sky surveys is optimized for small GW error volumes and for Laser Interferometer Gravitational-Wave Observatory/Virgo triggers &gt;50 M ⊙ .

We have shown previously that prostatic stem/progenitor cells can be purified from isolated prostate ducts, based on their high expression of the Sca-1 surface antigen. We now report that high levels of aldehyde dehydrogenase (ALDH) activity are present in a subset of prostate epithelial cells that coexpress a number of antigens found on stem/progenitor cells of other origins (CD9, Bcl-2, CD200, CD24, prominin, Oct 3/4, ABCG2, and nestin). Almost all of these cells expressing high levels of ALDH activity also express Sca-1 and a third of them express high levels of this antigen. The cells with high levels of ALDH activity have greater in vitro proliferative potential than cells with low ALDH activity. Importantly, in an in vivo prostate reconstitution assay, the cells expressing high levels of ALDH activity were much more effective in generating prostatic tissue than a population of cells with low enzymatic activity. Thus, a high level of ALDH activity can be considered a functional marker of prostate stem/progenitor cells and allows for simple, efficient isolation of cells with primitive features. The elucidation of the role of ALDH in prostate stem/progenitor cells may lead to the development of rational therapies for treating prostate cancer and benign prostatic hyperplasia.

We have previously shown that prostatic stem cells are located in the proximal region of mouse prostatic ducts. Here, we show that this region responds differently to transforming growth factor (TGF)-beta than the distal ductal region and that under physiological conditions androgens and TGF-beta are crucial overall regulators of prostatic tissue homeostasis. This conclusion is supported by the observations showing that high levels of TGF-beta signaling are present in the quiescent proximal region of ducts in an androgen-replete animal and that cells in this region overexpress Bcl-2, which protects them from apoptosis. Moreover, androgen ablation reverses the proximal-distal TGF-beta signaling gradient, leading to an increase in TGF-beta signaling in the unprotected distal region (low Bcl-2 expression). This reversal of TGF-beta-mediated signaling accompanies apoptosis of cells in the distal region and gland involution after androgen withdrawal. A physiological TGF-beta signaling gradient (high proximally and low distally) and its functional correlates are restored after androgen replenishment. In addition to highlighting the regulatory role of androgens and TGF-beta, these findings may have important implications for the deregulation of the stem cell compartment in the etiology of proliferative prostatic diseases.

Objective: This study analyzes how ethnicity, gender, and non-traditional student characteristics relate to differential online versus face-to-face outcomes in science, technology, engineering, and mathematics (STEM) courses at community colleges. Method: This study used a sample of 3,600 students in online and face-to-face courses matched by course, instructor, and semester from a large urban community college in the Northeast. Outcomes were measured using rates of successful course completion (with a “C−” or higher). Multilevel logistic regression and propensity score matching were utilized to control for unobserved heterogeneity between courses and for differences in student characteristics. Results: With respect to successful course completion, older students did significantly better online, and women did significantly worse (although no worse than men) online, than would be expected based on their outcomes in comparable face-to-face courses. There was no significant interaction between the online medium and ethnicity, suggesting that though Black and Hispanic students may do worse on average in STEM courses than their White and Asian peers both online and face-to-face, this gap was not increased by the online environment. Contributions: These findings suggest that both women and younger students in STEM courses may need extra support in the online environment. Future research is needed (a) to explore whether factors such as stereotype threat or child care responsibilities affect the outcomes of women in online STEM courses, and (b) to determine which characteristics (e.g., motivation, self-directed learning skills) of older students may make them particularly well suited to the online environment.

Raman spectroscopy is a sensitive method to detect early changes of molecular _composition and structure that occur in lesions during carcinogenesis. The Raman spectra of normal, benign and cancerous breast tissues were investigated in vitro using a near-infrared (NIR) Raman system of 785 nm excitation and confocal micro resonance Raman system of 532 nm excitation. A total number of 491 Raman spectra were acquired from normal, benign and cancerous breast tissues taken from 15 patients. When the 785 nm excitation was used, the dominant peaks in the spectra were characteristic of the vibrations of proteins and lipids. The differences between the normal and cancerous breast tissues were observed in both the peak positions and the intensity ratios of the characteristic Raman peaks in the spectral region of 700-1800 cm(21). With 532 nm excitation, the resonance Raman (RR) spectra exhibited a robust pattern of peaks within the region of 500-4000 cm(21). The intensities of four distinct peaks at 1156, 1521, 2854 and 3013 cm(21) detected in the spectra collected from normal breast tissue were found to be stronger in comparison with those collected from cancerous breast tissue. The twelve dramatically enhanced characteristic peaks, including the enhanced amide II peak at 1548 cm(21) in the spectra collected from cancerous breast tissue, distinguished the cancerous tissue from the normal tissue. Principal component analysis (PCA) combined with support vector machine (SVM) analysis of the Raman and RR spectral data yielded a high performance in the classification of cancerous and benign lesions from normal breast tissue.

Neanderthal diets are reported to be based mainly on the consumption of large and medium sized herbivores, while the exploitation of other food types including plants has also been demonstrated. Though some studies conclude that early Homo sapiens were active hunters, the analyses of faunal assemblages, stone tool technologies and stable isotopic studies indicate that they exploited broader dietary resources than Neanderthals. Whereas previous studies assume taxon-specific dietary specializations, we suggest here that the diet of both Neanderthals and early Homo sapiens is determined by ecological conditions. We analyzed molar wear patterns using occlusal fingerprint analysis derived from optical 3D topometry. Molar macrowear accumulates during the lifespan of an individual and thus reflects diet over long periods. Neanderthal and early Homo sapiens maxillary molar macrowear indicates strong eco-geographic dietary variation independent of taxonomic affinities. Based on comparisons with modern hunter-gatherer populations with known diets, Neanderthals as well as early Homo sapiens show high dietary variability in Mediterranean evergreen habitats but a more restricted diet in upper latitude steppe/coniferous forest environments, suggesting a significant consumption of high protein meat resources.

ABSTRACT We present the results of a systematic search for quasars in the Catalina Real-time Transient Survey exhibiting both strong photometric variability and spectroscopic variability over a decadal baseline. We identify 111 sources with specific patterns of optical and mid-infrared photometric behaviour and a defined spectroscopic change. These ‘changing-state’ quasars (CSQs) form a higher luminosity sample to complement existing sets of ‘changing-look’ AGNs and quasars in the literature. The CSQs (by selection) exhibit larger photometric variability than the changing-look quasars (CLQs). The spectroscopic variability is marginally stronger in the CSQs than CLQs as defined by the change in H β/[$\rm {O \,\rm {\small {III}}}$] ratio. We find 48 sources with declining H β flux and 63 sources with increasing H β flux, and discover 8 sources with $z$ &amp;gt; 0.8, further extending the redshift arm. Our CSQ sample compares to the literature CLQ objects in similar distributions of H β flux ratios and differential Eddington ratios between high (bright) and low (dim) states. Taken as a whole, we find that this population of extreme varying quasars is associated with changes in the Eddington ratio and the time-scales imply cooling/heating fronts propagating through the disc.