202 results match your criteria: "Graduate Center of CUNY[Affiliation]"

There is increasing interest in studying molecular motions in ionic liquids to gain better insights into their transport properties and to expand their applications. In this study, we have employed the fast field cycling relaxometry and pulsed field gradient nuclear magnetic resonance techniques to investigate the rotational and translational dynamics of fluorinated imide-based ionic liquids (ILs) at different temperatures. We have studied a total of six ILs composed of the 1-butyl-3-methylimidazolium cation ([BMIM]) combined with chemically modified analogs of the bis((trifluoromethyl)sulfonyl)imide anion ([NTf] or [TFSI]).

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Semiconductor nanomaterials and nanostructured interfaces have important technological applications, ranging from fuel production to electrosynthesis. Their photocatalytic activity is known to be highly heterogeneous, both in an ensemble of nanomaterials and within a single entity. Photoelectrochemical imaging techniques are potentially useful for high-resolution mapping of photo(electro)catalytic active sites; however, the nanoscale spatial resolution required for such experiments has not yet been attained.

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Background: To reduce substance use and sexual HIV transmission risk among sexual minority men (SMM) requires the development of interventions tailored for those in relationships. In the past 5 years, there have been considerable advances in the development of motivational nterviewing (MI) with couples. The Couples Health Project (CHP) is the first multi-session risk reduction protocol built on this formative research.

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Finding the E-channel proton loading sites by calculating the ensemble of protonation microstates.

Biochim Biophys Acta Bioenerg

January 2025

Department of Physics, The City College of New York, NY 10031, USA; Graduate Program In Biochemistry, The Graduate Center of CUNY, 365 5th Avenue, NY 10031, USA. Electronic address:

The aerobic electron transfer chain builds a proton gradient by proton coupled electron transfer reactions through a series of proteins. Complex I is the first enzyme in the sequence. Here transfer of two electrons from NADH to quinone yields four protons pumped from the membrane N- (negative, higher pH) side to the P- (positive, lower pH) side.

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Voltage-Driven Molecular Photoelectrocatalysis of Water Oxidation.

J Am Chem Soc

October 2024

Department of Chemistry and Biochemistry, Queens College-CUNY, Flushing, New York 11367, United States.

Molecular photocatalysis and photoelectrocatalysis have been widely used to conduct oxidation-reduction processes ranging from fuel generation to electroorganic synthesis. We recently showed that an electrostatic potential drop across the double layer contributes to the driving force for electron transfer (ET) between a dissolved reactant and a molecular catalyst immobilized directly on the electrode surface. In this article, we report voltage-driven molecular photoelectrocatalysis with a prevalent homogeneous water oxidation catalyst, (bpy)Cu (II), which was covalently attached to the carbon surface and exhibited photocatalytic activity.

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The past two decades have seen expanding interest in the application of Motivational Interviewing (MI) with couples. Thus far, literature detailing the development of MI with couples has focused primarily on elucidating counseling processes and techniques or on evaluating intervention effects. To date no published studies have examined client-perceptions of the counseling process in MI with couples.

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Microscopic inclusion statistics in a discrete one-body spectrum.

Phys Rev E

July 2024

Physics Department, the City College of New York, New York, New York 10031, USA and The Graduate Center of CUNY, New York, New York 10016, USA.

We present the microscopic formulation of inclusion statistics, a counterpoint to exclusion statistics in which particles tend to coalesce more than ordinary bosons. We derive the microscopic occupation multiplicities of one-body quantum states and show that they factorize into a product of clusters of neighboring occupied states with enhanced statistical weights. Applying this statistics to a one-dimensional gas of particles in a harmonic well leads to a Calogero-like n-body inclusion spectrum with interesting physical properties.

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Sodium-containing ionic liquids are very promising candidates as ion-conducting materials in alternative to electrolytes based on lithium chemistry. Here we investigate a series of seven ionic liquids with formula (EMImCl/(AlCl))/(δ-NaCl) (0≤x≤0.74).

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Quantitative Measurements of Electrocatalytic Reaction Rates with NanoSECM.

Anal Chem

April 2024

Department of Chemistry and Biochemistry, Queens College, Flushing, New York 11367, United States.

Scanning electrochemical microscopy (SECM) has been extensively used for mapping electrocatalytic surface reactivity; however, most of the studies were carried out using micrometer-sized tips, and no quantitative kinetic experiments on the nanoscale have yet been reported to date. As the diffusion-limited current density at a nanometer-sized electrode is very high, an inner-sphere electron-transfer process occurring at a nanotip typically produces a kinetic current at any attainable overpotential. Here, we develop a theory for substrate generation/tip collection (SG/TC) and feedback modes of SECM with a kinetic tip current and use it to evaluate the rates of hydrogen and oxygen evolution reactions in a neutral aqueous solution from the current-distance curves.

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Human locomotion is controlled by spinal neuronal networks of similar properties, function, and organization to those described in animals. Transspinal stimulation affects the spinal locomotor networks and is used to improve standing and walking ability in paralyzed people. However, the function of locomotor centers during transspinal stimulation at different frequencies and intensities is not known.

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Kidney diseases, both acute and chronic, are a substantial burden on individual and public health, and they continue to increase in frequency. Despite this and an intense focus on the study of disease mechanisms, few new therapeutic approaches have extended to the clinic. This is in part due to poor pharmacology of many, if not most, therapeutics with respect to the sites of kidney disease within the glomerulus or nephron.

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Background: Couples HIV testing and counseling (CHTC) is now a standard of care prevention strategy recommended by the Centers for Disease Control and Prevention for sexual minority men (SMM) in relationships. Despite standard recommendations that couples complete CHTC every 6-12 months, no study has empirically evaluated the effects associated with CHTC retesting.

Objective: This study aims to understand the benefits associated with continued dyadic engagement in the HIV prevention continuum through routine CHTC retesting, which is of particular importance for emerging-adult SMM in relationships who use drugs.

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Transference-focused psychotherapy (TFP) is an empirically supported treatment for borderline personality disorder (BPD) that improves functioning via targeting representations of self affectively relating to others, particularly as evoked in the therapeutic relationship. If change in TFP operates as theorized, then shifts in patterns of "self affectively relating to others" should be observed in the transference prior to shifts in daily relationships. Using ecological momentary assessment (EMA), a patient with BPD rated daily interpersonal events for 2-week periods during 18 months of TFP; at 9 and 18 months these ratings included interactions with the therapist.

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Protein dynamics govern the oxyferrous state lifetime of an artificial oxygen transport protein.

Biophys J

November 2023

Department of Physics, The City College of New York, New York, New York; Graduate Programs of Physics, Biology, Chemistry and Biochemistry, The Graduate Center of CUNY, New York, New York. Electronic address:

It has long been known that the alteration of protein side chains that occlude or expose the heme cofactor to water can greatly affect the stability of the oxyferrous heme state. Here, we demonstrate that the rate of dynamically driven water penetration into the core of an artificial oxygen transport protein also correlates with oxyferrous state lifetime by reducing global dynamics, without altering the structure of the active site, via the simple linking of the two monomers in a homodimeric artificial oxygen transport protein using a glycine-rich loop. The tethering of these two helices does not significantly affect the active site structure, pentacoordinate heme-binding affinity, reduction potential, or gaseous ligand affinity.

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Stimulant-use disorders can present with long-term cognitive and mental health deficits. Little is known about the underlying molecular mechanisms perpetuating sex differences in cognitive and behavioral deficits in preclinical models of addiction to stimulants such as methamphetamine (MA). The current study investigated the neurochemical shifts underlying sex disparities in MA-induced working memory deficits and an addictive phenotype following abstinence from chronic MA abuse.

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Cusp bifurcation in a metastatic regulatory network.

J Theor Biol

November 2023

Department of Mathematics, City College and the Graduate Center of CUNY, New York, NY 10031, USA. Electronic address:

Understanding the potential for cancers to metastasize is still relatively unknown. While many predictive methods may use deep learning or stochastic processes, we highlight a long standing mathematical concept that may be useful for modeling metastatic breast cancer systems. Ordinary differential equations (ODEs) can model cell state transitions by considering the pertinent environmental variables as well as the paths systems take over time.

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Visualizing Overall Water Splitting on Single Microcrystals of Phosphorus-Doped BiVO by Photo-SECM.

ACS Appl Mater Interfaces

October 2023

Department of Chemistry and Biochemistry, Queens College, Flushing, New York 11367, United States.

Particulate bismuth vanadate (BiVO) has attracted considerable interest as a promising photo(electro)catalyst for visible-light-driven water oxidation; however, overall water splitting (OWS) has been difficult to attain because its conduction band is too positive for efficient hydrogen evolution. Using photoscanning electrochemical microscopy (photo-SECM) with a chemically modified nanotip, we visualized for the first time the OWS at a single truncated bipyramidal microcrystal of phosphorus-doped BiVO. The tip simultaneously served as a light guide to illuminate the photocatalyst and an electrochemical nanoprobe to observe and quantitatively measure local oxygen and hydrogen fluxes.

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Several evidence-based psychotherapies for personality disorders have been developed in recent decades, including transference-focused psychotherapy (TFP), a contemporary model of psychodynamic psychotherapy developed by Otto Kernberg. Kernberg established Group TFP (TFP-G) as an alternative or adjunct treatment to individual TFP. Although not yet manualized, TFP-G is used in publicly and privately funded mental health services, including outpatient clinics, subacute hospitals, therapeutic inpatient units, partial hospitalization services, and rehabilitation services serving people with borderline personality.

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Matrix metalloproteinases (MMP) are enzymes that degrade the extracellular matrix and regulate essential normal cell behaviors. Inhibition of these enzymes has been a strategy for anti-cancer therapy since the 1990s, but with limited success. A new type of MMP-targeting strategy exploits the innate selective hydrolytic activity and consequent catalytic signal amplification of the proteinases, rather than inhibiting it.

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Modeling and analysis of affiliation networks with preferential attachment and subsumption.

Phys Rev E

July 2023

Department of Computer Science, The Graduate Center of CUNY, 365 5th Avenue, New York, New York 10016, USA.

Preferential attachment describes a variety of graph-based models in which a network grows incrementally via the sequential addition of new nodes and edges, and where existing nodes acquire new neighbors at a rate proportional to their degree. Some networks, however, are better described as groups of nodes rather than a set of pairwise connections. These groups are called affiliations, and the corresponding networks affiliation networks.

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Inclusion statistics and particle condensation in two dimensions.

Phys Rev E

June 2023

LPTMS, CNRS, Université Paris-Saclay, 91405 Orsay Cedex, France; Physics Department, the City College of New York, New York, New York 10031, USA; and The Graduate Center of CUNY, New York, New York 10016, USA.

We propose a type of quantum statistics which we call inclusion statistics, in which particles tend to coalesce more than ordinary bosons. Inclusion statistics is defined in analogy with exclusion statistics, in which statistical exclusion is stronger than in Fermi statistics, but now extrapolating beyond Bose statistics, resulting in statistical inclusion. A consequence of inclusion statistics is that the lowest space dimension in which particles can condense in the absence of potentials is d=2, unlike d=3 for the usual Bose-Einstein condensation.

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(L.) Dunal (family ) is a medicinal plant known for, among many pharmacological properties, an immune boosting effect. Our recent study revealed that its key immunostimulatory factor is lipopolysaccharide of plant-associated bacteria.

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Models of conditioned reinforcement and abnormal behaviour in captive animals.

Behav Processes

August 2023

Centre for the Study of Cultural Evolution, Stockholm University, 10691 Stockholm, Sweden; Department of Zoology, Stockholm University, 11418 Stockholm, Sweden.

Abnormal behaviours are common in captive animals, and despite a lot of research, the development, maintenance and alleviation of these behaviours are not fully understood. Here, we suggest that conditioned reinforcement can induce sequential dependencies in behaviour that are difficult to infer from direct observation. We develop this hypothesis using recent models of associative learning that include conditioned reinforcement and inborn facets of behaviour, such as predisposed responses and motivational systems.

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Structure of the complex between calmodulin and a functional construct of eukaryotic elongation factor 2 kinase bound to an ATP-competitive inhibitor.

J Biol Chem

June 2023

Department of Chemistry and Biochemistry, The City College of New York, New York, New York, USA; PhD Program in Biochemistry, The Graduate Center of CUNY, New York, New York, USA; PhD Program in Chemistry, The Graduate Center of CUNY, New York, New York, USA; PhD Program in Physics, The Graduate Center of CUNY, New York, New York, USA. Electronic address:

The calmodulin-activated α-kinase, eukaryotic elongation factor 2 kinase (eEF-2K), serves as a master regulator of translational elongation by specifically phosphorylating and reducing the ribosome affinity of the guanosine triphosphatase, eukaryotic elongation factor 2 (eEF-2). Given its critical role in a fundamental cellular process, dysregulation of eEF-2K has been implicated in several human diseases, including those of the cardiovascular system, chronic neuropathies, and many cancers, making it a critical pharmacological target. In the absence of high-resolution structural information, high-throughput screening efforts have yielded small-molecule candidates that show promise as eEF-2K antagonists.

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