City College of New York

We investigate the dynamics of a driven-dissipative polariton condensate in a GaAs microcavity under simultaneous excitations by a continuous laser and a pulsed laser. The femtosecond pulse destabilizes and quenches the condensate, which is then followed by a nonlinear luminescence surplus. Time-resolved photoluminescence shows a ring-like pattern in momentum space that shrinks as the condensate relaxes back to its steady state. The condensate also experiences an abrupt blueshift in energy after the pulse before returning to equilibrium. Simulations based on the driven-dissipative Gross-Pitaevskii equation confirm the importance of interactions between exciton reservoir and polaritons. This study clarifies how reservoir-mediated interactions shape the nonlinear processes underlying polariton condensation.

Lateralized auditory processing is essential for specialized functions such as speech processing, typically dominated by the Left Auditory Cortex (ACx) in humans. Hemispheric specializations also occur in the adult mouse ACx, but their developmental origins are unclear. Our study finds that the Left and Right ACx in mice reach developmental milestones at different ages. Thalamocortical responses and maturation of synaptic dynamics develop earlier in the Right ACx than the Left. We show that this timing offset predicts hemisphere-dependent differences in sensory-driven plasticity. Juvenile tone exposure at specific times results in imbalanced adult tone frequency representations in the Right and Left ACx. Additionally, sex influences the timing of plasticity; female Right ACx plasticity occurs before male Right ACx, and female Left ACx aligns with male Right ACx plasticity. Our findings demonstrate that sex and hemispheric identity drive asynchronous development and contribute to functional differences in sensory cortices.

Extratropical cyclones are the main providers of midlatitude precipitation, but how they will change in a warming climate is unclear. The latest NASA Goddard Institute for Space Studies (GISS) Earth system models (ESMs) accurately simulate the location and structure of cyclones, though deficiencies in the depiction of cloud and precipitation are found. To provide a new process-level context for the evaluation of simulated cloud and precipitation in the midlatitudes, occluded cyclones are examined. Such cyclones are characterized by the formation of a thermal ridge, maintained via latent heat release in the wider three-dimensional trough of warm air aloft (TROWAL) in the occluded sector. Using a novel method for the objective identification of occluded cyclones, the simulation of occlusions in the latest GISS-E3 model is examined. The model produces occluded cyclones, adequately depicting the thermal and kinematic structures of the thermal ridge, with realistic depth and poleward tilt. Nevertheless, E3 occlusions are less frequent than observed and systematically shifted poleward and toward the exit region of the climatological storm tracks. Compared to CloudSat–CALIPSO cloud retrievals across the thermal ridge, the dependence of cloud properties on thermal ridge strength is well represented, though at the expense of producing low ice mass clouds too often at high altitudes (i.e., “too many, too tenuous”). Overall, E3 produces significantly more precipitation in occluded versus nonoccluded cyclones, demonstrating the importance of accurately representing occlusions and associated hydrological processes in ESMs.

Hw has the unprecedented salience of anti-Asian racism resulting from the COVID-19 pandemic influenced Asian Americans’ coalitional attitudes, both within-group and towards other racial minorities? Asian Americans, as the fastest-growing racial minority group in the United States, could play a key role in advancing racial justice. However, Asian Americans’ ambivalent racialization as valorized relative to Latino and Black Americans raises uncertainty as to how they will engage with other communities of color and racial politics. Using observational survey data from the 2016 and 2020 Collaborative Multiracial Post Election Study and an original survey experiment, we find that COVID-19 era anti-Asian racism can begin to facilitate Asian American alignment with other communities of color, but it depends on how the issue is framed and only specific subsets of Asian Americans who are less socialized in racial discourses are persuaded by these frames. This study assesses the challenges and possibilities of facilitating Asian American solidarity with other racial minorities.

Humans are not perfect at selectively responding to one stimulus while ignoring others visible at the same time. In spatial filtering tasks , this imperfect selectivity is often measured by how the judgment of the relevant stimulus depends on whether an irrelevant stimulus is associated with the same response. Such congruency effects decline with increasing spatial separation between stimuli and are minimal for widely separated stimuli. However, there is evidence that divided attention can increase congruency effects even for widely separated stimuli. We investigated this possibility for a pair of widely separated stimuli and a simple yes/no detection task. Performance was measured for a single task (only one of the stimuli was task-relevant) and for a dual task (both of the stimuli were task-relevant). In the single task there were small congruency effects, whereas in the dual task larger congruency effects occurred despite the widely separated stimuli. Results from a second experiment with sequential and simultaneous presentations were consistent with the congruency effect being due to later processes such as memory or decision rather than immediate processes such as perception. Additional results comparing high and low performance levels were consistent with congruency effects being due to a graded process such as attenuation or crosstalk rather than an all-or-none process such as blocking or substitution. These results rule out many possible theories of spatial selectivity. Our working hypothesis is that spatial selection can protect against interactive processing of multiple stimuli for a single task but not for dual tasks.

In the midlatitudes, extratropical cyclones produce the majority of winter precipitation. Precipitation rates and accumulation depend strongly on both the cyclone intensity and the environmental moisture amount. Using 5 years of the Integrated Multi‐satellitE Retrievals for Global Precipitation Measurement (IMERG) product, cyclone‐centered composites of surface precipitation rates are compared between cyclones that occlude and those that do not. Occluding cyclones produce greater surface precipitation because they tend to be more intense. When the non‐occluding cyclones are selected such that they collectively have similar intensity and moisture amount distributions as the occluding cyclones, precipitation rates at peak intensity are still larger for occluding cyclones. This is because a particular type of forced, frontal‐scale, ascent in the occluded thermal ridge, unique to occluded cyclones by virtue of their thermal structure, favors more precipitation. The results demonstrate that life‐cycle type (i.e., achieving occlusion vs. not) matters for precipitation production in extratropical cyclones.

Electric fields used in clinical trials with transcranial direct current stimulation (tDCS) are small, with magnitudes that have yet to demonstrate measurable effects in preclinical animal models. We hypothesized that weak stimulation will nevertheless produce sizable effects, provided that it is applied concurrently with behavioral training, and repeated over multiple sessions. We tested this here in a rodent model of dexterous motor-skill learning. We developed a preparation that allows concurrent stimulation during the performance of a pellet-reaching task in freely behaving rats. The task was automated to minimize experimenter bias. We measured field magnitudes intracranially to calibrate the stimulation current. In this study, only male rats were used. Animals were trained for 20 min with concurrent epicranial tDCS over 10 daily sessions. Behavior was recorded with high-speed video to quantify reaching dynamics. We also measured motor-evoked potentials (MEPs) bilaterally with epidural microstimulation. The new electrode montage enabled stable stimulation over 10 sessions with a field intensity of 2V/m at the motor cortex. The number of successful reaches improved across days of training, and the rate of learning was higher in the anodal group as compared to sham-control animals (F(1)=7.12, p=0.008, N=24). MEPs were not systematically affected by tDCS. Post hoc analysis suggests that tDCS modulated motor learning only for right-pawed animals, improving success of reaching, but limiting stereotypy in these animals. Repeated and concurrent anodal tDCS can boost motor-skill learning at clinically-relevant field intensities. In this animal model the effect interacted with paw preference and was not associated with corticospinal excitability. Significance Statement The effects of tDCS have been explored in numerous human clinical trials, but the mechanisms of action of weak electric fields remain unclear. In vitro studies show that constant electric fields at 2.5 V/m can enhance the efficacy of synapses undergoing plasticity. This study demonstrates in a rodent model that tDCS of only 2 Vm when applied concurrently to behavioral training can improve motor skill learning, and reduce stereotypy of reaching behavior. These effects accumulated over 10 days of training. Motor evoked potentials (MEP), which are often used to demonstrate plastic effects in humans on a time scale of hours, were not measurably affected by tDCS on this longer time scale.

Palladium-catalyzed C–N bond forming reactions and Heck arylations involve reaction of an aryl halide at either a nitrogen or carbon atom, respectively. A suitable catalyst-ligand combination and a base are generally employed in both. With substrates containing both an amino group and a vinyl moiety, control of C–N versus C–C reactivity will provide a method to regiodivergent functionalization. With such a focus, reactions of 8-vinyl adenosine and 2’-deoxyadenosine with aryl bromides and iodides have been probed herein. Pd(OAc)2, Pd2(dba)3, and preformed dichloro[1,1’-bis(di-t-butylphosphino)ferrocene]palladium (II) (Pd-118) were tested as metal sources. Supporting ligands analyzed were Xantphos, DPEphos, BIPHEP, and DPPF, while Cs2CO3, and K3PO4 were tested as bases. In toluene as solvent, the Pd(OAc)2/Xantphos/Cs2CO3 combination was uniquely capable of promoting N6 arylation predominantly. Aryl bromides and iodides gave comparable product yields. However, replacement of Cs2CO3 with K3PO4 switches reactivity from N6 arylation to predominant Cvinyl arylation, as did all other combinations of catalyst, ligand, and bases that were tested. Changing the Pd source from Pd(OAc)2 to Pd2(dba)3 resulted in loss of chemoselectivity. Two structurally similar catalytic systems that gave selective Cvinyl and N6 arylation reactions were then used to accomplish sequential arylation of the nucleosides at the 8-vinyl and N6 moieties. To demonstrate further applications, products from these reactions were converted to other novel nucleoside analogues. The photophysical properties of fluorescent compounds were experimentally and computationally assessed.

Nucleotide excision repair (NER) represents one of the major molecular machineries that control chromosome stability in all living species. In Eubacteria, the initial stages of the repair process are carried out by the UvrABC excinuclease complex. Despite the wealth of structural data available, some crucial details of the pathway remain elusive. In this study, we present a structural investigation of the Mycobacterium tuberculosis UvrAUvrB complex and of the UvrA dimer, both in complex with damaged DNA. Our analyses yield insights into the DNA binding mode of UvrA, showing an unexplored conformation of Insertion Domains (IDs), underlying the essential role of these domains in DNA coordination. Furthermore, we observe an interplay between the ID and the UvrB Binding Domain (UBD): after the recognition of the damage, the IDs repositions with the concomitant reorganization of UBD, allowing the formation of the complex between UvrA and UvrB. These events are detected along the formation of the uncharacterized UvrA2UvrB1-DNA and the UvrA2UvrB2-DNA complexes which we interpret as hierarchical steps initiating the DNA repair cascade in the NER pathway, resulting in the formation of the pre-incision complex.

Thermal and mechanical tissue stimulation is widely utilized in various medical contexts, particularly to enhance local circulation, alleviate pain, and restore movement. Techniques to objectively quantify the physiological effects of these interventions support therapeutic efficacy and explain clinical benefits. Here we conducted a pilot trial to evaluate the feasibility of magnetic resonance imaging (MRI) technology to provide an objective assessment of acute treatment effects in enhancing blood flow. Subjects () received an MRI flow quantification scan of the abdominal aorta before and immediately after undergoing a 20‐min thermo‐mechanical massage delivered to the lumbar spine by a commercial automated device. We report a significant increase of 27% in the peak velocity of blood flow following treatment. There were no significant changes in the volume of the imaged vessel, in mean heart rate, or heart rate variability (HRV), which is consistent with direct local effects of therapy on circulation. These findings are consistent with the potential utility of MRI in detecting and quantifying regional increases in blood flow following thermo‐mechanical stimulation.

Background Morocco’s national breast cancer screening program (NBCSP) was launched in 2010 in response to rising breast cancer incidence. The program comprises clinical breast examination (CBE) and diagnostic mammography and aims to improve early diagnosis and breast cancer management. This study evaluated key performance indicators of the NBCSP for the Casablanca-Settat region from 2018 to 2021. Methods Aggregated regional data on screening and diagnostic activities under the NBCSP were extracted from a health information system. Annual screening coverage, participation, CBE-positivity, and breast cancer detection rates for the region were then calculated. Screening numbers and CBE positivity rates were compared by year and sub-region using one-way ANOVA and Bonferroni multiple-comparison tests. Trends in breast cancer screenings were also compared using Pearson’s correlation coefficients and statistical trend tests. Results From 2018 to 2021, a total of 846,692 women in the Casablanca-Settat region were screened under the NBCSP, and 21,476 referred for a positive CBE to a designated secondary referral center for diagnostic mammography. Annual screening coverage rates of eligible women ranged from 10.4 to 28.8% during the study period. Only two out of nine administrative sub-regions in Casablanca-Settat achieved a desired 40% screening coverage threshold. Overall, annual participation among the target population from 2018 to 2021 decreased by 44.8%. Annual CBE positivity rates remained stable between 2.2 and 2.7%, though notable variations were observed at the sub-regional level. Over one-third (36.4%, n = 7,808) of CBE-positive women sought consultations at designated secondary referral centers in the region. Compliance to further diagnostic testing at these centers increased overtime, from 24.2% in 2018 to 61.9% in 2021. Breast cancer detection rates in the region from 2018 to 2021 were: 0.7, 0.8, 1.0, to 1.1 per 1000 women screened, respectively. Conclusions The NBCSP fell short of achieving its desired performance benchmarks in the Casablanca-Settat region from 2018 to 2021, notably in screening coverage, participation, and CBE positivity rates. Annual breast cancer detection rates under the program also remained low. Additional interventions are needed to increase screening participation, standardize CBE training, and establish linkages between health facilities to limit the underestimation of breast cancer under the NBCSP.

Rapid re‐organization of e‐commerce supply chains has resulted in outdated land use and transportation policies that do not align with modern freight operations. This article, drawing from prior work by the author and other researchers, outlines the disconnects that exist between e‐commerce facilities, vehicles, and travel demand characteristics and current policies, and provides recommendations for updating zoning, curb management and space allocation, and vehicle operating regulations to address the needs of freight stakeholders.

The current study investigates the conjoint effect of prenatal Superstorm Sandy stress (SS) and postnatal parenting, as measured by affectionless control (AC), in determining the risk of early childhood psychopathology. The study included 154 children (45.5% males) longitudinally tracked from ages 2–5 years. Maternal AC was assessed using the Parental Bonding Instrument. The prevalence of child diagnostic outcomes (DSM-IV anxiety disorders, phobias, and disruptive behavior disorders) was ascertained by trained clinical interviewers using maternal responses to the Preschool Age Psychiatric Assessment. Children were stratified into four groups by SS and AC status to identify synergistic effects on psychopathology exceeding the risks expected in an additive model. Children exposed to both SS and AC had an over 5-fold increased risk of any anxiety disorder, a 12-fold increased risk for disruptive behavior disorders, and a nearly 5-fold increased risk of any disorder relative to the reference group of children with neither exposure. The risks of anxiety, disruptive behavior, and any disorders were synergistically greater than the sum of independent effects of the two stressors, as evident in the synergy index. Evaluation of synergistically increased risks for childhood disorders will help to identify high-risk children, which in turn could inform design of multi-level interventions to mitigate child psychopathology.

Terrestrial ecosystem respiration (Re) is a crucial component of the carbon cycle and is expected to increase with anthropogenic warming. The temperature response of Re is typically parameterized using temperature sensitivity Q10, which describes the increase in respiration with a 10oC rise in temperature. The respiration increase largely determines the future direction of the terrestrial-atmosphere carbon balance. However, our current understanding of the mechanisms driving Q10 variation across latitudes and biomes is still insufficient. As a result, it remains difficult to constrain predictions of future Re dynamics. The Michaelis–Menten (MM) kinetics , developed to describe enzyme-catalyzed reactions, is a cornerstone to understand biochemical processes at the cellular and molecular levels. This model effectively captures the relationship between substrate concentration and reaction rates, simplifying complex biochemical interactions into manageable mathematical expressions using the key parameters Vmax (maximum reaction rate) and Km (substrate concentration at half the maximum rate). However, the applicability of this microscopic model to large-scale ecosystem processes can be questioned . Most Earth system models incorporate the Farquhar–von Caemmerer–Berry (FvCB) biochemical model, which is grounded in Michaelis–Menten kinetics, to simulate photosynthesis at ecosystem or larger scales. However, the description of respiration processes over large ecosystem scale still predominantly relies on more empirical models, projecting an exponential temperature response with Arrhenius or Q10 types of functions.

A growing number of organic materials have recently been reported to achieve room‐temperature exciton‐polariton (polariton) condensation, which is an essential requirement for practical polaritonic applications. Notably, fluorescent dyes utilizing the small‐molecule, ionic isolation lattice (SMILES) method have solved the long‐standing challenges of conventional organic dyes and have been successfully implemented in cavities to realize condensation. However, almost all demonstrations of molecular polariton condensates have inherently large spectral linewidth and poor temporal coherence arising from intrinsic disorder and low quality (Q) factor of the cavity. Here, exciton‐polaritons are realised using fluorescent dye SMILES in a high Q factor microcavity and we observe polariton condensates with a linewidth of 175 µeV. These polariton condensates exhibit temporal coherence of 30.3 ± 8.0 ps, indicating the highly coherent nature of the narrow linewidth condensates. These results set the stage for realizing highly coherent and robust polaritonic devices operating at room temperature.