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Researchers investigated the compounds which form during the fabrication of the matallization structure of very large and ultralarge scale integration complementary metal oxide semiconductor integrated circuits. They used x-ray diffraction to reveal the effects of factors including annealing temperature and the TiN diffusion barrier thickness on phase formations.

Analysis of barium-strontium titanate (Ba0.5Sr0.5)TiO3 thin film capacitors developed by a spin-on technique suggests that the films have a dielectric constant of 22 to 151 at 1 MHz at room temperature. In the frequency range 10 Hz-10 MHz, the films display semicircular behavior suggestive of current leakage, which varies with the dielectric constant. The film porosity and structure are influenced by annealing temperature and thermal exposure time.

Reactive evaporation and rapid thermal annealing yield thin TiN layers on Si and SiO2 substrates. The thin layers have a TiSi2 layer between the TiN layer and the Si substrate. TiN layer properties such as composition, resistivity and stress are obtained experimentally using elastic recoil detection. The resistivity is 40 microohms and the stress ranges between 1 and 6 giga pascals. The ratio of nitrogen to titanium varies between 0.8 and 1.

We report on the effect of substrate biasing on the properties of high-dielectric constant (high-k) titanium silicate (TixSi1-xO2) thin films deposited with a room-temperature magnetron-sputtering process. The composition, microstructure, and electrical properties of the TixSi1-xO2 films were systematically characterized, as a function of the substrate bias voltage (VS), by means of various complementary techniques, including x-ray photoelectron spectroscopy, x-ray reflectivity, Rutherford backscattering spectrometry, and appropriate electrical characterizations. We show, in particular, that depositing the TixSi1-xO2 films with a relatively small biasing voltage (VS≈-15 V) leads not only to a significant reduction of their porosity but more interestingly to a marked improvement of their electrical properties. A further increase of the negative bias voltage (from 20 to 110 V) was, however, found to increase progressively the leakage current through the TixSi1-xO2 films. Such a degradation of the electrical properties at high VS values is shown to be associated with some resputtering and defects generation caused by the rather energetic bombardment conditions. In contrast, the “soft hammering” induced by the relatively low-energy ion bombardment densifies the films and improves their properties. Under the optimal substrate biasing conditions (VS∼-15 V), the room-temperature deposited titanium silicate films are shown to exhibit a highly attractive combination of electrical properties, namely a k value as high as ∼17, a dissipation factor <0.01, a leakage current as low as 5×10-9 A/cm2 at 1 MV/cm, and a breakdown field higher than 4 MV/cm. [ABSTRACT FROM AUTHOR]

Elastic recoil detection (ERD) aids the definition of the stoichiometry of TiN layers that are created by reactive evaporation and quick thermal annealing. The forward direction of an incident ion beam from the matrix is identified due to ERD. The use of ERD in combination with time of flight (TOF) technique makes the stoichiometry detection for all elements possible at the same time.

Titanium silicate (TixSi1-xO2) nanocomposite thin films containing dispersed TiO2 nanocrystallites have been grown by means of an optimized sol-gel process. The size of the TiO2 nanoprecipitates was varied from ∼1 to 22 nm by controlling the content of the TiO2 component of the films. For the Ti0.40Si0.60O2 film composition, which contains TiO2 nanoparticles of ∼1 nm diameter, regular oscillations are observed in their conductance-voltage characteristics in the mid-to-high-fields range. This abnormal behavior can be interpreted by single-electron tunneling at room temperature between the TiO2 nanocrystallites separated by the wider band-gap amorphous TixSi1-xO2 phase. [ABSTRACT FROM AUTHOR]

We report on the successful growth of amorphous TiSiO[sub x] thin films by means of pulsed-laser ablation of a TiO[sub 2]/SiO[sub 2] composite target in a high-vacuum chamber. The room-temperature resistivity of the TiSiO[sub x] films is found to decrease by more than 6 orders of magnitude (i.e., from ∼2×10[sup 4] to 10[sup -2] Ω cm) when their substrate deposition temperature (T[sub d]) is increased from 20 to 600 °C. On the other hand, by subjecting these films to a post-deposition annealing at 600 °C in oxygen atmosphere, they become highly insulating with a resistivity level as high as 2×10[sup 10] Ω cm, regardless of the T[sub d] value. The presence of conductive titanium silicide and titanium sub-oxide local phases in the as-deposited TiSiO[sub x] films, as revealed by photoelectron spectroscopy analyses, appears to be the cause of the observed tremendous change in the film resistivity. In particular, it is shown that the resistivity of the TiSiO[sub x] films is strongly correlated with their oxygen content. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Illicit drug injection typically occurs in private or semi-public settings where two or more injectors are present. In a large sample of young adult injectors (aged 15-30) in five US cities, we describe those who reported consistently injecting by themselves in a recent period. Among 3199 eligible subjects, 85% were male, median age was 24 years, and median number of years injecting was four. Fifteen percent (n=467) who reported always injecting alone in the previous 3 months were compared to other IDUs to understand the relationship between this practice and injection risk behavior. IDUs who reported injecting alone were substantially less likely to report injection with a syringe (AOR=0.16, 95% CI 0.1-0.2) or other drug preparation equipment (AOR=0.17, 95% CI 0.13-0.2) previously used by another injector. Markedly low rates of injection risk behavior were observed in IDUs who reported injecting alone; this practice may facilitate safe injection by granting the individual greater control over the injection setting. However, risks may include accidental overdose with severe consequences. [ABSTRACT FROM AUTHOR]

Importance: Opioid-related overdose accounts for almost 80 000 deaths annually across the US. People who use drugs leaving jails are at particularly high risk for opioid-related overdose and may benefit from take-home naloxone (THN) distribution., Objective: To estimate the population impact of THN distribution at jail release to reverse opioid-related overdose among people with opioid use disorders., Design, Setting, and Participants: This study developed the agent-based Justice-Community Circulation Model (JCCM) to model a synthetic population of individuals with and without a history of opioid use. Epidemiological data from 2014 to 2020 for Cook County, Illinois, were used to identify parameters pertinent to the synthetic population. Twenty-seven experimental scenarios were examined to capture diverse strategies of THN distribution and use. Sensitivity analysis was performed to identify critical mediating and moderating variables associated with population impact and a proxy metric for cost-effectiveness (ie, the direct costs of THN kits distributed per death averted). Data were analyzed between February 2022 and March 2024., Intervention: Modeled interventions included 3 THN distribution channels: community facilities and practitioners; jail, at release; and social network or peers of persons released from jail., Main Outcomes and Measures: The primary outcome was the percentage of opioid-related overdose deaths averted with THN in the modeled population relative to a baseline scenario with no intervention., Results: Take-home naloxone distribution at jail release had the highest median (IQR) percentage of averted deaths at 11.70% (6.57%-15.75%). The probability of bystander presence at an opioid overdose showed the greatest proportional contribution (27.15%) to the variance in deaths averted in persons released from jail. The estimated costs of distributed THN kits were less than $15 000 per averted death in all 27 scenarios., Conclusions and Relevance: This study found that THN distribution at jail release is an economical and feasible approach to substantially reducing opioid-related overdose mortality. Training and preparation of proficient and willing bystanders are central factors in reaching the full potential of this intervention.

Aging is associated with dysfunction in the cholinergic system, including degeneration of basal forebrain cholinergic terminals that innervate the cortex, which directly contributes to age- and disease-related cognitive decline. In this study, we used [18F]fluoroethoxybenzovesamicol ([18F]FEOBV) positron emission tomography (PET) imaging to assess the effect of age on cholinergic terminal integrity in predefined regions of interest and its relationship to cognitive performance in healthy older adults who underwent neuropsychological assessment and FEOBV PET brain imaging. Our results showed age-related reductions in FEOBV binding, particularly in the anterior cingulate cortex-our primary region of interest-as well as in the striatum, posterior cingulate cortex, and primary auditory cortex. Notably, FEOBV binding in the anterior cingulate cortex was positively correlated with cognitive performance on the NIH EXAMINER Executive Composite Score. These findings suggest that [18F]FEOBV PET imaging can be used as a reliable biomarker to assess cholinergic changes in the human brain and indicate that preserving the cholinergic integrity of the basal forebrain may help maintain cognitive function and protect against age-related cognitive decline.

Background and Hypothesis: Disturbances of the narrative self and personal identity accompany the onset of psychotic disorders in late adolescence and early adulthood (a formative developmental stage for self-concept and personal narratives). However, these issues have primarily been studied retrospectively after illness onset, limiting any inferences about their developmental course., Study Design: Youth at clinical high risk for psychosis (CHR) (n = 49) and matched healthy comparison youth (n = 52) completed a life story interview (including self-defining memory, turning point, life challenge, and psychotic-like experience) and questionnaires assessing self-esteem, self-beliefs, self-concept clarity, and ruminative/reflective self-focus. Trained raters coded interviews for narrative identity themes of emotional tone, agency, temporal coherence, context coherence, self-event connections, and meaning-making (intraclass correlations >0.75). Statistical analyses tested group differences and relationships between self-concept, narrative identity, symptoms, and functioning., Study Results: CHR participants reported more negative self-esteem and self-beliefs, poorer self-concept clarity, and more ruminative self-focus, all of which related to negative symptoms. CHR participants narrated their life stories with themes of negative emotion and passivity (ie, lack of personal agency), which related to positive and negative symptoms. Reflective self-focus and autobiographical reasoning were unaffected and correlated. Autobiographical reasoning was uniquely associated with preserved role functioning., Conclusions: This group of youth at CHR exhibited some, but not all, changes to self-concept and narrative identity seen in psychotic disorders. A core theme of negativity, uncertainty, and passivity ran through their semantic and narrative self-representations. Preserved self-reflection and autobiographical reasoning suggest sources of resilience and potential footholds for cognitive-behavioral and metacognitive interventions., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Objective: To identify tools that predict the risk of complications for patients presenting to an outpatient clinic or an emergency department (ED) with influenza-like illness., Methods: We searched Medline, Embase, Cochrane Library and CINAHL from inception to July 2023. We included articles reporting on the derivation or validation of a score or algorithm used to stratify the risk of hospitalization or mortality among patients with influenza-like illness in the ED or outpatient clinic., Results: Twelve articles reporting on eight scores and six predictive models were identified. For predicting the need for hospitalization, the area under the curve (AUC) of the PMEWS and the CURB-65 ranged respectively from 0.76 to 0.94, and 0.65 to 0.88. The Community Assessment Tool had an AUC of 0.62. For predicting inpatient mortality, AUC was 0.66 for PMEWS and 0.79 for CURB-65, 0.79 for the SIRS criteria and 0.86 for the qSOFA score. Two scores were developed without external validation during the Covid-19 pandemic. The CovHos score and the Canadian Covid discharge score had an AUC ranged from 0.70 to 0.91. The predictive models performed adequately (AUC from 0.76 to 0.92) but will require external validation for clinical use. Tool diversity and study population heterogeneity precluded meta-analysis., Conclusion: Although the CURB, PMEWS and qSOFA scores appear to predict accurately the risk of complications of influenza-like illness, none were reliable enough to justify their widespread ED use. Refinement of an existing tool or development of a new tool to optimize the management of these patients is needed., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Simon Berthelot reports article publishing charges was provided by Quebec Ministry of the Economy and Innovation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier Ltd.)

In recent years, a new rehabilitation programme has been developed on the Hudson Bay coast of Nunavik. The purpose of this article is to reflect on the experience of an occupational and physical therapy programme development in an Inuit sociocultural context. To do so, the challenges encountered during the first years following the implementation of rehabilitation services and the strategies implemented by the professionals to overcome them were identified, examined in the light of the literature, and discussed with members of the rehabilitation team. The challenges encountered and strategies implemented were divided into 10 major themes: (1) diverse clinical needs; (2) communication issues; (3) acquisition of cross-cultural interaction and population-specific knowledge; (4) adaptation of clinical practice to Nunavimmiut; (5) client engagement in rehabilitation; (6) professional isolation; (7) lack of awareness around the objectives and scope of rehabilitation practice; (8) use of culturally safe assessment tools; (9) staff turnover; (10) large geographic area to be served. This exercise highlighted the need to adapt clinical rehabilitation practices to Nunavimmiut's worldviews and culture, as well as to adopt a reflective practice in order to improve the quality, relevance and effectiveness of rehabilitation services.

The prolonged masking of auditory inputs with white noise has been shown to reopen the critical period for spectral tuning in the adult rat auditory cortex. Here, we argue that the masking of salient temporal inputs in particular is responsible for changes in neuronal activity that lead to this experience-dependent plasticity. We tested this hypothesis by passively exposing adult rats to 2 weeks of amplitude-modulated (AM) white noise with different modulation depths from 0% (no modulation) to 100% (strong modulation). All exposed rats displayed evidence of cortical plasticity as measured by receptive field bandwidths, tonotopic gradients, and synchronization during spontaneous activity. However, this plasticity was fundamentally different in nature for rats exposed to unmodulated noise, as a second passive exposure to pure tones elicited tonotopic reorganization in rats exposed to 0% AM noise only. Detection of c-FOS expression in excitatory and inhibitory cells through post-mortem immunohistochemistry also revealed different patterns of cellular activation depending on modulation depth. Together, these results indicate that the absence of temporal modulation promotes noise-induced plasticity in the adult auditory cortex and suggest an important and continuous role for temporally salient inputs in the maintenance of mature auditory circuits.

During early developmental windows known as critical periods (CPs) of plasticity, passive alterations in the quality and quantity of sensory inputs are sufficient to induce profound and long-lasting distortions in cortical sensory representations. With CP closure, those representations are stabilized, a process requiring the maturation of inhibitory networks and the maintenance of sufficient GABAergic tone in the cortex. In humans and rodents, however, cortical inhibition progressively decreases with advancing age, raising the possibility that the regulation of plasticity could be altered in older individuals. Here we tested the hypothesis that aging results in a destabilization of sensory representations and maladaptive dysregulated plasticity in the rat primary auditory cortex (A1). Consistent with this idea, we found that passive tone exposure is sufficient to distort frequency tuning in the A1 of older but not younger adult rats. However, we also found that these passive distortions decayed rapidly, indicating an ongoing instability of A1 tuning in the aging cortex. These changes were associated with a decrease in GABA neurotransmitter concentration and a reduction in parvalbumin and perineuronal net expression in the cortex. Finally, we show that artificially increasing GABA tone in the aging A1 is sufficient to restore representational stability and improve the retention of learning.

Objective: Older persons with HIV are at risk for impaired cognition, yet there is limited information on modifiable factors associated with neurocognitive function in this group., Design: This is a cross-sectional observational study of cognitive activities and neurocognitive function., Methods: We examined the relation between frequency of cognitive activity and current neurocognitive performance in 176 older persons with HIV [70% African American, 76% men; mean age = 58.7 (SD = 5.5); mean education = 13.2 (SD = 2.8)]., Results: In linear regression models adjusted for demographic variables, we found that higher frequency of cognitive activity was associated with better cognition in global cognition, semantic memory, and perceptual speed. Subsequent models that examined the role of race demonstrated that the association was significant only among Blacks for global cognition, episodic memory, working memory, and perceptual speed (interaction of cognitive activity by race: Estimate range = 0.38-0.55; all P < 0.05)., Conclusion: Greater frequency of cognitive activity is associated with better neurocognitive function in older persons with HIV, particularly older Blacks. Longitudinal studies are needed to assess the relation of cognitive activity to change in neurocognitive function in older persons with HIV., Competing Interests: Alan L. Landay is on the Scientific Advisory Board for Merck. Lisa L. Barnes is the recipient of grants mentioned above and has no other conflicts of interest. For the remaining authors no conflict of interests or funding sources have been declared.

We used the rat primary auditory cortex (A1) as a model to probe the effects of cholinergic enhancement on perceptual learning and auditory processing mechanisms in both young and old animals. Rats learned to perform a two-tone frequency discrimination task over the course of two weeks, combined with either the administration of a cholinesterase inhibitor or saline. We found that while both age groups learned the task more quickly through cholinergic enhancement, the young did so by improving target detection, whereas the old did so by inhibiting erroneous responses to nontarget stimuli. We also found that cholinergic enhancement led to marked functional and structural changes within A1 in both young and old rats. Importantly, we found that several functional changes observed in the old rats, particularly those relating to the processing and inhibition of nontargets, produced cortical processing features that resembled those of young untrained rats more so than those of older adult rats. Overall, these findings demonstrate that combining auditory training with neuromodulation of the cholinergic system can restore many of the auditory cortical functional deficits observed as a result of normal aging and add to the growing body of evidence demonstrating that many age-related perceptual and neuroplastic changes are reversible.

In both humans and rodents, decline in cognitive function is a hallmark of the aging process; the basis for this decrease has yet to be fully characterized. However, using aged rodent models, deficits in auditory processing have been associated with significant decreases in inhibitory signaling attributed to a loss of GABAergic interneurons. Not only are these interneurons crucial for pattern detection and other large-scale population dynamics, but they have also been linked to mechanisms mediating plasticity and learning, making them a prime candidate for study and modeling of modifications to cortical communication pathways in neurodegenerative diseases. Using the rat primary auditory cortex (A1) as a model, we probed the known markers of GABAergic interneurons with immunohistological methods, using antibodies against gamma aminobutyric acid (GABA), parvalbumin (PV), somatostatin (SOM), calretinin (CR), vasoactive intestinal peptide (VIP), choline acetyltransferase (ChAT), neuropeptide Y (NPY), and cholecystokinin (CCK) to document the changes observed in interneuron populations across the rat's lifespan. This analysis provided strong evidence that several but not all GABAergic neurons were affected by the aging process, showing most dramatic changes in expression of parvalbumin (PV) and somatostatin (SOM) expression. With this evidence, we show how understanding these trajectories of cell counts may be factored into a simple model to quantify changes in inhibitory signaling across the course of life, which may be applied as a framework for creating more advanced simulations of interneuronal implication in normal cerebral processing, normal aging, or pathological processes.

This paper presents a buried quad p-n junction (BQJ) photodetector fabricated with a HV (high-voltage) CMOS process. Multiple buried junction photodetectors are wavelength-sensitive devices developed for spectral analysis applications where a compact integrated solution is preferred over systems involving bulk optics or a spectrometer due to physical size limitations. The BQJ device presented here is designed for chip-based biochemical analyses using simultaneous fluorescence labeling of multiple analytes such as with advanced labs-on-chip or miniaturized photonics-based biosensors. Modeling and experimental measurements of the spectral response of the device are presented. A matrix-based method for estimating individual spectral components in a compound spectrum is described. The device and analysis method are validated via a test setup using individually modulated LEDs to simulate light from 4-component fluorescence emission.