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Recent theories suggest that low frequency dynamic intramolecular and intermolecular motions in organic semiconductors (OSCs) are critical to determining the hole mobility. So far, however, it has not been possible to probe these motions directly experimentally and therefore no unequivocal and quantitative link exists between molecular-scale thermal disorder and macroscale hole mobility in OSCs. Here we use inelastic neutron scattering to probe thermal disorder directly by measuring the phonon spectrum in six different small molecule OSCs, which we accurately reproduce with first principles simulations. We use the simulated phonons to generate a set of electron-phonon coupling parameters. Using these parameters, the theoretical mobility is in excellent agreement with macroscopic measurements. Comparison of mobility between different materials reveals routes to improve mobility by engineering phonon and electron-phonon coupling.

Conformational and energetic disorder in organic semiconductors reduces charge and exciton transport because of the structural defects, thus reducing the efficiency in devices such as organic photovoltaics and organic light-emitting diodes. The main structural heterogeneity is because of the twisting of the polymer backbone that occurs even in polymers that are mostly crystalline. Here, we explore the relationship between polymer backbone twisting and exciton delocalization by means of transient absorption spectroscopy and density functional theory calculations. We study the PffBT4T-2DT polymer which has exhibited even higher device efficiency with nonfullerene acceptors than the current record breaking PCE11 polymer. We determine the driving force for planarization of a polymer chain caused by excitation. The methodology is generally applicable and demonstrates a higher penalty for nonplanar structures in the excited state than in the ground state. This study highlights the morphological and electronic changes in conjugated polymers that are brought about by excitation.

In speech perception, low-frequency cortical activity tracks hierarchical linguistic units (e.g., syllables, phrases, and sentences) on top of acoustic features (e.g., speech envelope). Since the fluctuation of speech envelope typically corresponds to the syllabic boundaries, one common interpretation is that the acoustic envelope underlies the extraction of discrete syllables from continuous speech for subsequent linguistic processing. However, it remains unclear whether and how cortical activity encodes linguistic information when the speech envelope does not provide acoustic correlates of syllables. To address the issue, we introduced a frequency-tagging speech stream where the syllabic rhythm was obscured by echoic envelopes and investigated neural encoding of hierarchical linguistic information using electroencephalography (EEG). When listeners attended to the echoic speech, cortical activity showed reliable tracking of syllable, phrase, and sentence levels, among which the higher-level linguistic units elicited more robust neural responses. When attention was diverted from the echoic speech, reliable neural tracking of the syllable level was also observed in contrast to deteriorated neural tracking of the phrase and sentence levels. Further analyses revealed that the envelope aligned with the syllabic rhythm could be recovered from the echoic speech through a neural adaptation model, and the reconstructed envelope yielded higher predictive power for the neural tracking responses than either the original echoic envelope or anechoic envelope. Taken together, these results suggest that neural adaptation and attentional modulation jointly contribute to neural encoding of linguistic information in distorted speech where the syllabic rhythm is obscured by echoes.

For patients with disorders of consciousness (DoC), accurate assessment of residual consciousness levels and cognitive abilities is critical for developing appropriate rehabilitation interventions. In this study, we investigated the potential of electrooculography (EOG) in assessing language processing abilities and consciousness levels. Patients’ EOG data and related electrophysiological data were analysed before and after explicit language learning. The results showed distinct differences in vocabulary learning patterns among patients with varying levels of consciousness. While minimally conscious patients showed significant neural tracking of artificial words and notable learning effects similar to those observed in healthy controls, whereas patients with unresponsive wakefulness syndrome did not show such effects. Correlation analysis further indicated that EOG detected vocabulary learning effects with comparable validity to electroencephalography, reinforcing the credibility of EOG indicator as a diagnostic tool. Critically, EOG also revealed significant correlations between individual patients’ linguistic learning performance and their Oromotor/verbal function as assessed through behavioural scales. In conclusion, this study explored the differences in language processing abilities among patients with varying consciousness levels. By demonstrating the utility of EOG in evaluating consciousness and detecting vocabulary learning effects, as well as its potential to guide personalised rehabilitation, our findings indicate that EOG indicators show promise as a rapid, accurate and effective additional tool for diagnosing and managing patients with DoC.

Summary: Humans can quickly adapt to recognize acoustically degraded speech, and here we hypothesize that the quick adaptation is enabled by internal linguistic feedback – Listeners use partially recognized sentences to adapt the mapping between acoustic features and phonetic labels. We test this hypothesis by quantifying how quickly humans adapt to degraded speech and analyzing whether the adaptation process can be simulated by adapting an automatic speech recognition (ASR) system based on its own speech recognition results. We consider three types of acoustic degradation, i.e., noise vocoding, time compression, and local time-reversal. The human speech recognition rate can increase by >20% after exposure to just a few acoustically degraded sentences. Critically, the ASR system with internal linguistic feedback can adapt to degraded speech with human-level speed and accuracy. These results suggest that self-supervised learning based on linguistic feedback is a plausible strategy for human adaptation to acoustically degraded speech.

The computational principles underlying attention allocation in complex goal-directed tasks remain elusive. Goal-directed reading, that is, reading a passage to answer a question in mind, is a common real-world task that strongly engages attention. Here, we investigate what computational models can explain attention distribution in this complex task. We show that the reading time on each word is predicted by the attention weights in transformer-based deep neural networks (DNNs) optimized to perform the same reading task. Eye tracking further reveals that readers separately attend to basic text features and question-relevant information during first-pass reading and rereading, respectively. Similarly, text features and question relevance separately modulate attention weights in shallow and deep DNN layers. Furthermore, when readers scan a passage without a question in mind, their reading time is predicted by DNNs optimized for a word prediction task. Therefore, we offer a computational account of how task optimization modulates attention distribution during real-world reading.

Heartbeat-evoked responses (HERs) can interact with external stimuli and play a crucial role in shaping perception, self-related processes, and emotional processes. On the one hand, the external stimulus could modulate HERs. On the other hand, the HERs could affect cognitive processing of the external stimulus. Whether the same neural mechanism underlies these two processes, however, remains unclear. Here, we investigated this interactive mechanism by measuring HERs using magnetoencephalography (MEG) and two name perception tasks. Specifically, we tested (1) how hearing a subject's own name (SON) modulates HERs and (2) how the judgment of an SON is biased by prestimulus HERs. The results showed a dual interaction between HERs and SON. In particular, SON can modulate HERs for heartbeats occurring from 200 to 1200 ms after SON presentation. In addition, prestimulus HERs can bias the SON judgment when a stimulus is presented. Importantly, MEG activities from these two types of interactions differed in spatial and temporal patterns, suggesting that they may be associated with distinct neural pathways. These findings extend our understanding of brain-heart interactions.

Working memory load can modulate speech perception. However, since speech perception and working memory are both complex functions, it remains elusive how each component of the working memory system interacts with each speech processing stage. To investigate this issue, we concurrently measure how the working memory load modulates neural activity tracking three levels of linguistic units, i.e., syllables, phrases, and sentences, using a multiscale frequency-tagging approach. Participants engage in a sentence comprehension task and the working memory load is manipulated by asking them to memorize either auditory verbal sequences or visual patterns. It is found that verbal and visual working memory load modulate speech processing in similar manners: Higher working memory load attenuates neural activity tracking of phrases and sentences but enhances neural activity tracking of syllables. Since verbal and visual WM load similarly influence the neural responses to speech, such influences may derive from the domain-general component of WM system. More importantly, working memory load asymmetrically modulates lower-level auditory encoding and higher-level linguistic processing of speech, possibly reflecting reallocation of attention induced by mnemonic load.

Natural scenes contain multi-modal information, which is integrated to form a coherent perception. Previous studies have demonstrated that cross-modal information can modulate neural encoding of low-level sensory features. These studies, however, mostly focus on the processing of single sensory events or rhythmic sensory sequences. Here, we investigate how the neural encoding of basic auditory and visual features is modulated by cross-modal information when the participants watch movie clips primarily composed of non-rhythmic events. We presented audiovisual congruent and audiovisual incongruent movie clips, and since attention can modulate cross-modal interactions, we separately analyzed high- and low-arousal movie clips. We recorded neural responses using electroencephalography (EEG), and employed the temporal response function (TRF) to quantify the neural encoding of auditory and visual features. The neural encoding of sound envelope is enhanced in the audiovisual congruent condition than the incongruent condition, but this effect is only significant for high-arousal movie clips. In contrast, audiovisual congruency does not significantly modulate the neural encoding of visual features, e.g., luminance or visual motion. In summary, our findings demonstrate asymmetrical cross-modal interactions during the processing of natural scenes that lack rhythmicity: Congruent visual information enhances low-level auditory processing, while congruent auditory information does not significantly modulate low-level visual processing.

Human language is generally combinatorial: Words are combined into sentences to flexibly convey meaning. How the brain represents sentences, however, remains debated. Recently, it has been shown that delta-band cortical activity correlates with the sentential structure of speech. It remains debated, however, whether delta-band cortical tracking of sentences truly reflects mental representations of sentences or is caused by neural encoding of semantic properties of individual words. The current study investigates whether delta-band neural tracking of speech can be explained by semantic properties of individual words. Cortical activity is recorded using electroencephalography (EEG) when participants listen to sentences repeating at 1 Hz and word lists. The semantic properties of individual words, simulated using a word2vec model, predict a stronger 1 Hz response to word lists than to sentences. When listeners perform a word-monitoring task that does not require sentential processing, the 1 Hz response to word lists, however, is much weaker than the 1 Hz response to sentences, contradicting the prediction of the lexical semantics model. When listeners are explicitly asked to parse word lists into multi-word chunks, however, cortical activity can reliably track the multi-word chunks. Taken together, these results suggest that delta-band neural responses to speech cannot be fully explained by the semantic properties of single words and are potentially related to the neural representation of multi-word chunks.

Architects should consider the aesthetic experience of potential users when designing architectures. Previous studies have shown that subjective aesthetic judgment of architectures is influenced by structure features, and Western observers prefer structures that have curvilinear contours, high ceilings, and open space. The building styles, however, vary across cultures, and it remains unclear whether the preference for contours, ceiling height, and openness exist across cultures. To investigate this issue, this study analyzes the aesthetic judgment of Chinese observers, and the results demonstrate that Chinese observers also prefer high ceilings and open space. Preference for curvilinear contours, however, interacts with ceiling height and openness. Simple effect analysis reveals that Chinese observers prefer curvilinear contours only when the ceiling is low and the space is closed. In sum, these results suggest that preference for high ceilings and open space is robust for Chinese observers, but the preference for curvilinear contours is less reliable.

Effective diagnosis and prognosis of patients with disorders of consciousness (DOC) provides a basis for family counseling, decision-making, and the design of rehabilitation programs. However, effective and objective bedside evaluation is a challenging problem. In this study, we explored electroencephalography (EEG) response tracking sound rhythms as potential neural markers for DOC evaluation. We analyzed the responses to natural speech and tones modulated at 2 and 41 Hz. At the population level, patients with positive outcomes (DOC-P) showed higher cortical synchronization to modulated tones at 41 Hz compared with patients with negative outcomes (DOC-N). At the individual level, phase coherence to modulated tones at 41 Hz was significantly correlated with Coma Recovery Scale-Revised (CRS-R) and Glasgow Outcome Scale-Extended (GOS-E) scores. Furthermore, SVM classifiers, trained using phase coherences in higher frequency bands or combination of the low frequency aSSR and speech tracking responses, performed very well in diagnosis and prognosis of DOC. These findings show that EEG response to auditory rhythms is a potential tool for diagnosis, severity, and prognosis of DOC.

Speech contains rich acoustic and linguistic information. Using highly controlled speech materials, previous studies have demonstrated that cortical activity is synchronous to the rhythms of perceived linguistic units, for example, words and phrases, on top of basic acoustic features, for example, the speech envelope. When listening to natural speech, it remains unclear, however, how cortical activity jointly encodes acoustic and linguistic information. Here we investigate the neural encoding of words using electroencephalography and observe neural activity synchronous to multi-syllabic words when participants naturally listen to narratives. An amplitude modulation (AM) cue for word rhythm enhances the word-level response, but the effect is only observed during passive listening. Furthermore, words and the AM cue are encoded by spatially separable neural responses that are differentially modulated by attention. These results suggest that bottom-up acoustic cues and top-down linguistic knowledge separately contribute to cortical encoding of linguistic units in spoken narratives.

The ability to detect visual targets in complex background varies across individuals and are affected by factors such as stimulus saliency and top-down attention. Here, we investigated how the saliency of visual background (naturalistic cartoon video vs. blank screen) and top-down attention (single vs. dual tasks) separately affect individual ability to detect visual targets. Behaviorally, we found that target detection accuracy decreased and reaction time elongated when the background was salient or during dual tasking. The EEG response to visual background was recorded using a novel stimulus tagging technique. This response was strongest in occipital electrodes and was sensitive to background saliency but not dual tasking. In contrast, the event-related potential (ERP) evoked by the visual target was strongest in central electrodes, and was affected by both background saliency and dual tasking. With a cartoon background, the EEG responses to visual targets, presented in the central visual field, and the EEG responses to peripheral visual background could both predict individual target detection performance. When these two responses were combined, better prediction was achieved. These results suggest that neural processing of visual targets and background jointly contribute to individual visual target detection performance.

Chunking is a key mechanism for sequence processing. Studies on speech sequences have suggested low-frequency cortical activity tracks spoken phrases, that is, chunks of words defined by tacit linguistic knowledge. Here, we investigate whether low-frequency cortical activity reflects a general mechanism for sequence chunking and can track chunks defined by temporarily learned artificial rules. The experiment records magnetoencephalographic (MEG) responses to a sequence of spoken words. To dissociate word properties from the chunk structures, two tasks separately require listeners to group pairs of semantically similar or semantically dissimilar words into chunks. In the MEG spectrum, a clear response is observed at the chunk rate. More importantly, the chunk-rate response is task-dependent. It is phase locked to chunk boundaries, instead of the semantic relatedness between words. The results strongly suggest that cortical activity can track chunks constructed based on task-related rules and potentially reflects a general mechanism for chunk-level representations.

Our eyes constantly follow objects we see, but do they also move in synchrony with auditory inputs? Here, the authors show that eyelid movements track the temporal structure of speech and other sound sequences, which could reflect a role of motor systems in temporal attention and sequence processing.

In music, chords are organized into hierarchical structures based on recursive or embedded syntax. How the brain extracts recursive grammar is a central question in musical cognition and other cognitive neuroscience, but the precise mechanism remains unclear. By analyzing event related potentials (ERPs) and neural oscillatory activity, the present study investigated neurocognitive mechanisms underlying the processing of center-embedded structure in music by examining the differences in center-embedded and non-embedded structure processing and evaluating how these differences are affected by musical proficiency. Based on Western musical proficiency, the subjects were divided into two groups, non-experts and experts. The results revealed that for non-experts, the processing of center-embedded structure elicited greater early right-anterior negativity (ERAN) and N5 components as well as, reduced alpha and gamma activities than did the non-embedded structure. For experts, no significant difference in the ERP response was observed between the processing of non-embedded and center-embedded structures; however, the processing of center-embedded structure elicited increased beta activity compared to non-embedded structure. These findings indicate that listeners different in proficiency would rely on different cognitive neural mechanisms in music processing with the syntactic complexity increases.

Rapidly grouping local elements into an organized object (i.e., perceptual integration) is a fundamental yet challenging task, especially in noisy contexts. Previous studies demonstrate that ventral visual pathway, which is widely known to mediate object recognition, engages in the process by conveying object-level information processed in high-level areas to modulate low-level sensory areas. Meanwhile, recent evidence suggests that the dorsal visual pathway, which is not typically attributable to object recognition, is also involved in the process. However, the underlying whole-brain fine spatiotemporal neuronal dynamics remains unknown. Here we used magnetoencephalography (MEG) recordings in combination with a temporal response function (TRF) approach to dissociate the time-resolved neuronal response that specifically tracks the perceptual grouping course. We demonstrate that perceptual integration initiates robust and rapid responses along the dorsal visual pathway in a reversed hierarchical manner, faster than the ventral pathway. Specifically, the anterior intraparietal sulcus (IPS) responds first (i.e., within 100 ms), followed by activities backpropagating along the dorsal pathway to early visual areas (EVAs). The IPS activity causally modulates the EVA response, even when the global form information is task-irrelevant. The IPS-to-EVA response profile fails to appear when the global form could not be perceived. Our results support the crucial function of the dorsal visual pathway in perceptual integration, by quickly extracting a coarse global template (i.e., an initial object representation) within first 100 ms to guide subsequent local sensory processing so that the ambiguities in the visual inputs can be efficiently resolved.

To understand speech, listeners have to combine the words they hear into phrases and sentences. Recent magnetoencephalography (MEG) and electrocorticography (ECoG) studies show that cortical activity is concurrently entrained/synchronized to the rhythms of multiple levels of linguistic units including words, phrases, and sentences. Here we investigate whether this phenomenon can be observed using electroencephalography (EEG), a technique that is more widely available than MEG and ECoG. We show that the EEG responses concurrently track the rhythms of hierarchical linguistic units such as syllables/words, phrases, and sentences. The strength of the sentential-rate response correlates with how well each subject can detect random words embedded in a sequence of sentences. In contrast, only a syllabic-rate response is observed for an unintelligible control stimulus. In sum, EEG provides a useful tool to characterize neural encoding of hierarchical linguistic units, potentially even in individual participants.

Shannon’s source entropy formula is not appropriate to measure the uncertainty of non-stationary processes. In this paper, we propose a new entropy measure for non-stationary processes, which is greater than or equal to Shannon’s source entropy. The maximum entropy of the non-stationary process has been considered, and it can be used as a design guideline in cryptography.

This study investigated how speech recognition in noise is affected by language proficiency for individual non-native speakers. The recognition of English and Chinese sentences was measured as a function of the signal-to-noise ratio (SNR) in sixty native Chinese speakers who never lived in an English-speaking environment. The recognition score for speech in quiet (which varied from 15%-92%) was found to be uncorrelated with speech recognition threshold (SRTQ/2), i.e. the SNR at which the recognition score drops to 50% of the recognition score in quiet. This result demonstrates separable contributions of language proficiency and auditory processing to speech recognition in noise.

Thermophysical properties of adsorbates and gas-phase species define the free energy landscape of heterogeneously catalyzed processes and are pivotal for an atomistic understanding of the catalyst performance. These thermophysical properties, such as the free energy or the enthalpy, are typically derived from density functional theory (DFT) calculations. Enthalpies are species-interdependent properties that are only meaningful when referenced to other species. The widespread use of DFT has led to a proliferation of new energetic data in the literature and databases. However, there is a lack of consistency in how DFT data is referenced and how the associated enthalpies or free energies are stored and reported, leading to challenges in reproducing or utilizing the results of prior work. Additionally, DFT suffers from exchange-correlation errors that often require corrections to align the data with other global thermochemical networks, which are not always clearly documented or explained. In this review, we introduce a set of consistent terminology and definitions, review existing approaches, and unify the techniques using the framework of linear algebra. This set of terminology and tools facilitates the correction and alignment of energies between different data formats and sources, promoting the sharing and reuse of ab initio data. Standardization of thermochemistry concepts in computational heterogeneous catalysis reduces computational cost and enhances fundamental understanding of catalytic processes, which will accelerate the computational design of optimally performing catalysts.

This study evaluated the effects of community engagement through social accountability on service users' values, attitudes and interactions. We conducted a pre-post study of the community and provider driven social accountability intervention (CaPSAI) over a 12-month period among 1,500 service users in 8 health facilites in Ghana and in Tanzania (n = 3,000).In both countries, there were significant improvements in women's participation in household decision-making and in how service users' perceive their treatment by health workers. In both settings, however, there was a decline in women's knowledge of rights, perception of service quality, awareness of accountability mechanisms and collective efficacy in the community. Though CaPSAI intervention set out to change the values, attitudes, and interactions between community members and those providing contraceptive services, there were changes in different directions that require closer examination., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: Although contraceptive use has increased over 15 years, discontinuation rates remain high. Contraceptive use is becoming more important when addressing unmet need for family planning. Social accountability, defined here as collective processes for holding duty bearers to account for their actions, is a rights-based participatory process that supports service provision and person-centred care, as well as, informed decision-making among community members regarding their health. A study implemented in Ghana and Tanzania was designed to understand and evaluate how social accountability and participatory processes influences quality of care and client satisfaction and whether this results in increased contraceptive uptake and use. We report here on the relationship between social accountability and the use of modern contraceptives, i.e., contraceptive method discontinuation, contraceptive method switching, and contraceptive discontinuation., Methods: As part of Community and Provider driven Social Accountability Intervention (CaPSAI) Project, a cohort of women aged 15 to 49 years who were new users of contraception and accessing family planning and contraceptives services at the study facilities across both intervention and control groups were followed-up over a 12-month period to measure changes contraceptive use., Results: In this cohort study over a one-year duration, we did not find a statistically significant difference in Ghana and Tanzania in overall method discontinuation, switching, and contraceptive discontinuation after exposure to a social accountability intervention. In Ghana but not in Tanzania, when stratified by the type of facility (district level vs. health centre), there were significantly less method and contraceptive discontinuation in the district level facility and significantly more method and contraceptive discontinuation in the health centres in the intervention group. In Ghana, the most important reasons reported for stopping a method were fear of side-effects, health concerns and wanting to become pregnant in the control group and fear of side-effects wanting a more effective method and infrequent sex in the intervention group. In Tanzania, the most important reasons reported for stopping a method were fear of side-effects, wanting a more effective method, and method not available in the control group compared to wanting a more effective method, fear of side-effects and health concerns in the intervention group., Conclusions: We did not demonstrate a statistically significant impact of a six-month CaPSAI intervention on contraceptives use among new users in Tanzania and Ghana. However, since social accountability have important impacts beyond contraceptive use it is important consider results of the intermediate outcomes, cases of change, and process evaluation to fully understand the impact of this intervention., Trial Registration: The CaPSAI Project has been registered at Australian New Zealand Clinical Trials Registry (ACTRN12619000378123, 11/03/2019)., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Previous research has shown that clients are better able to achieve their reproductive intentions when family planning (FP) services meet their needs and they have satisfying client provider interactions. There are several areas of quality provider-client communication, including providers taking a complete reproductive history of their clients to best gauge their needs, communication around alternative FP methods and side effects captured in the method information index, and communication around sexually transmitted infections and HIV risk as it relates to FP choices. This study examines data from a clinic-based intervention in Togo that focuses on strengthening health provider counseling related to FP, including improving in these three areas of provider-client communication. A clustered sampling approach was used to select 650 FP clients from 23 intervention facilities and 235 clients from 17 control facilities in the Lomé and Kara districts of Togo. The FP clients' interactions with providers were observed and clients exit interviews were conducted in December 2021. For each communication area measured through client interviews and observations, principal components analysis and Cronbach's alpha scores were used to ensure that the individual components could be indexed. Outcomes variables based on an index of sub-questions were then created for those who had fulfilled each of the components within an index. Multivariate multilevel mixed-effects logit models accounted for clients nested within facilities and included independent variables capturing client demographic and facility variables. Multivariate results show that all three outcome variables representing the three provider-client communication areas were statistically significantly better for FP clients in intervention clinics versus control clinics (p<0.05). The results speak to the emphasis that the Togo Ministry of Health has placed on building the provider capacity to provide quality counseling and administration of FP methods and working to assist in achieving health programming goals through well-designed interventions., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Bellow et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Social accountability, which is defined as a collective process for holding duty bearers and service providers to account for their actions, has shown positive outcomes in addressing the interrelated barriers to quality sexual and reproductive health services. The Community and Provider driven Social Accountability Intervention (CaPSAI) Project contributes to the evidence on the effects of social accountability processes in the context of a family planning and contraceptive programme., Methods: A quasi-experimental study utilizing an interrupted time series design with a control group (ITS-CG) was conducted to determine the actual number of new users of contraception amongst women 15-49 years old in eight intervention and eight control facilities per country in Ghana and Tanzania. A standardized facility audit questionnaire was used to collect facility data and completed every year in both intervention and control groups in each country from 2018-2020., Results: In Ghana, the two-segmented Poisson Generalized Estimating Equation (GEE) model demonstrated no statistically significant difference at post-intervention, between the intervention and control facilities, in the level of uptake of contraceptives (excess level) (p-value = 0.07) or in the rate of change (excess rate) in uptake (p-value = 0.07) after adjusting for baseline differences. Similarly, in Tanzania, there was no statistical difference between intervention and control facilities, in the level of uptake of contraceptives (excess level) (p-value = 0.20), with the rate of change in uptake (p-value = 0.05) after adjusting for the baseline differences. There was no statistical difference in the level of or rate of change in uptake in the two groups in a sensitivity analysis excluding new users recruited in outreach activities in Tanzania., Conclusions: The CAPSAI project intervention did not result in a statistically significant increase in uptake of contraceptives as measured by the number of or increase in new users. In evaluating the impact of the intervention on the intermediate outcomes such as self-efficacy among service users, trust and countervailing power among social groups/networks, and responsiveness of service providers, cases of change and process evaluation should be considered., Trial Registration: The CaPSAI Project has been registered at the Australian New Zealand Clinical Trials Registry (ACTRN12619000378123, 11/03/2019)., (© 2022. The Author(s).)

Objective: To explore the effectiveness, safety and cost between urinary follicle stimulating hormone (uFSH) and recombinant follicle stimulating hormone (rFSH) in controlled ovarian stimulation (COS) in China. Methods: Data were collected from 16 reproductive centers in China covering oocytes collection time from May 1, 2015 to June 30, 2018. Eligible patients were over 18 years old, adopting COS with uFSH (uFSH group) or rFSH (rFSH group) as start gonadotropins (Gn), and using in vitro fertilization (IVF) and (or) intracytoplasmic sperm injection for fertilisation, excluding frozen embryo recovery cycle. Generalised estimating equation was used to address the violation of independency assumption between cycles due to multiple IVF cycles for one person and clustering nature of cycles carried out within one center. Controlling variables included age, body mass index, anti-Müllerian hormone level, cause of infertility, ovulation protocol, type of fertilisation, number of embryos transferred, number of days of Gn use. Results: Totally 102 061 cycles met eligibility criteria and were included in the analyses. In terms of effectiveness, after controlling relevant unbalanced baseline characteristics, compared with rFSH group, the high oocyte retrieval (>15 oocytes was considered high retrieval) rate of uFSH group significantly decreased in gonadotropin-releasing hormone agonist protocol ( OR =0.642, P <0.01) and in gonadotropin-releasing hormone antagonist protocol ( OR =0.556, P =0.001), but the clinical pregnancy rate per transfer cycle and the live birth rate per transfer cycle significantly increased ( OR =1.179, OR =1.169, both P <0.01) in both agonist and antagonist protocols. For safety, multiple analysis result demonstrated that in the agonist protocol, compared with rFSH group, the incidence of moderate to severe ovarian hyperstimulation syndrome of uFSH group significantly decreased ( OR =0.644, P =0.002). The differences in ectopic pregnancy rate and multiple pregnancy rate between the uFSH and rFSH groups were not significant ( P =0.890, P =0.470) in all patients. In terms of cost, compared with rFSH group, the uFSH group had lower total Gn costs for each patient ( P <0.01). Conclusion: For patients who underwent COS, uFSH has better safety, and economic profiles over rFSH in China.

Depot medroxyprogesterone acetate administered subcutaneously (DMPA-SC) is an all-in-one injectable contraceptive administered every 3 months, either by a trained health care provider or community health worker or by training a client to self-inject. Using a prospective cohort of family planning (FP) clients in Ghana, this study explores patterns of DMPA-SC use and mode of injection administration over a 6-month period. This study also examines the predictors of self-injection adoption 6 months after initiating DMPA-SC. Our analysis focuses on 378 women who were using DMPA-SC at the 6-month interview. Adjusted odds ratios accounting for clustering show that clients who were new FP users, never married, or attended high school/attained higher education were significantly more likely to self-inject by the third injection. Results of this study suggest that in Ghana, adding DMPA-SC to the method mix may improve access to FP, especially among new users. Results of this study may inform FP projects and programs aiming to improve access to contraceptive methods and increase contraceptive prevalence by introducing or scaling up DMPA-SC self-injection. The findings also provide a sociodemographic profile of FP clients most likely to adopt DMPA-SC self-injection over time, which could serve as an evidence base for social marketing strategies., (© Nai et al.)

An interrupted time series with a parallel control group (ITS-CG) design is a powerful quasi-experimental design commonly used to evaluate the effectiveness of an intervention, on accelerating uptake of useful public health products, and can be used in the presence of regularly collected data. This paper illustrates how a segmented Poisson model that utilizes general estimating equations (GEE) can be used for the ITS-CG study design to evaluate the effectiveness of a complex social accountability intervention on the level and rate of uptake of modern contraception. The intervention was gradually rolled-out over time to targeted intervention communities in Ghana and Tanzania, with control communities receiving standard of care, as per national guidelines. Two ITS GEE segmented regression models are proposed for evaluating of the uptake. The first, a two-segmented model, fits the data collected during pre-intervention and post-intervention excluding that collected during intervention roll-out. The second, a three-segmented model, fits all data including that collected during the roll-out. A much simpler difference-in-difference (DID) GEE Poisson regression model is also illustrated. Mathematical formulation of both ITS-segmented Poisson models and that of the DID Poisson model, interpretation and significance of resulting regression parameters, and accounting for different sources of variation and lags in intervention effect are respectively discussed. Strengths and limitations of these models are highlighted. Segmented ITS modelling remains valuable for studying the effect of intervention interruptions whether gradual changes, over time, in the level or trend in uptake of public health practices are attributed by the introduced intervention. Trial Registration : The Australian New Zealand Clinical Trials registry. Trial registration number : ACTRN12619000378123. Trial Registration date : 11-March-2019., Competing Interests: Conflict of interestNo competing interests were declared., (© The Author(s) 2020.)

Background : There are numerous barriers leading to a high unmet need for family planning and contraceptives (FP/C).  These include limited knowledge and information, poor access to quality services, structural inefficiencies in service provision and inadequately trained and supervised health professionals. Recently, social accountability programs have shown promising results in addressing barriers to accessing sexual and reproductive health services. As a highly complex participatory process with multiple and interrelated components, steps and actors, studying social accountability poses methodological challenges. The Community and Provider driven Social Accountability Intervention (CaPSAI) Project study protocol was developed to measure the impact of a social accountability intervention on contraceptive uptake and use and to understand the mechanisms and contextual factors that influence and generate these effects (with emphasis on health services actors and community members). Methods : CaPSAI Project is implementing a social accountability intervention where service users and providers assess the quality of local FP/C services and jointly identify ways to improve the delivery and quality of such services. In the project, a quasi-experimental study utilizing an interrupted time series design with a control group is conducted in eight intervention and eight control facilities in each study country, which are Ghana and Tanzania. A cross-sectional survey of service users and health care providers is used to measure social accountability outcomes, and a cohort of women who are new users of FP/C is followed up after the completion of the intervention to measure contraceptive use and continuation. The process evaluation utilizes a range of methods and data sources to enable a fuller description of how the findings were produced. Conclusion : This complex study design could provide researchers and implementers with the means to better measure and understand the mechanisms and contextual factors that influence social accountability processes in reproductive health, adding important findings to the evidence base., Competing Interests: No competing interests were disclosed., (Copyright: © 2020 Steyn PS et al.)

Aim: This study explored adolescent experiences and coping strategies for unintended pregnancy in two informal settlements-Viwandani and Korogocho-in Nairobi, Kenya., Methods: Forty-nine in-depth-interviews and eight focus group discussions were conducted with male and female adolescents aged 15-19 years from households in two informal settlements. Participants were purposively selected to include adolescents of varying socio-demographic characteristics, including the married and unmarried, and adolescents who had never/ever been pregnant. Data were transcribed, translated verbatim and analyzed thematically., Results: Adolescents attributed unintended pregnancy to poverty, sexual violence and inconsistent contraceptive use. Lack of parental support and guidance, as well as household conflicts also exposed girls to early sexual debut and risky sexual behavior. Decisions about pregnancy management centered on carrying the pregnancy to term or terminating it. Deciding to terminate a pregnancy was not always straightforward and was motivated by concerns about stigma or shame, and school disruption. Participants reiterated that carrying an unintended pregnancy to term disrupts adolescents' schooling, with few girls returning to school after childbirth. Upon deciding to carry a pregnancy to term, adolescents used several coping strategies such as relocating from usual residence, hiding until delivery and planning to put up the child for adoption upon delivery., Conclusions: Early interventions to provide adolescents with comprehensive pregnancy prevention information and to address sexual violence and poverty can prevent unintended pregnancy in adolescents. Efforts to support adolescents to positively cope with unintended pregnancy and facilitate re-entry to school are also warranted., Competing Interests: The authors declare that no competing interests exist.

Background: Changes in the values, attitudes, and interactions of both service users and health care providers are central to social accountability processes in reproductive health. However, there is little consensus on how best to measure these latent changes. This paper reports on the adaptation and validation of measures that capture these changes in Tanzania and Ghana., Methods: The CaPSAI theory of change determined the dimensions of the measure, and we adapted existing items for the survey items. Trained data collectors used a survey to collect data from 752 women in Tanzania and 750 women in Ghana attending contraceptive services. We used reliability analysis, exploratory, and confirmatory factor analysis to assess the validity and reliability of these measures in each country., Results: The measure has high construct validity and reliability in both countries. We identified several subscales in both countries, 10 subscales in Tanzania, and 11 subscales in Ghana. Many of the domains and items were shared across both settings., Conclusion: The study suggests that the multi-dimensional scales have high construct validity and reliability in both countries. Though there were differences in the two country contexts and in items and scales, there was convergence in the analysis that suggests that this measure may be relevant in different settings and should be validated in new settings., Trial Registration: ACTRN12619000378123 .

Background: Child marriage remains a challenge in Ghana. Over the years, government and development partners have made various commitments and efforts to curb the phenomenon of child marriage. However, there is little empirical evidence on the predictors, norms and practices surrounding the practice to support their efforts, a gap this study sought to fill., Methods: The study employed a multiple-method approach to achieve the set objectives. Data from the women's file of the 2014 Ghana Demographic and Health Survey (GDHS) was used to examine the predictors of child marriage using frequencies and logistic regression methods. Data from Key Informant Interviews (KIIs) and Focus Group Discussions (FGDs) collected in Central and Northern regions of Ghana were used to examine norms and practices surrounding child marriage using thematic analysis., Results: Two in ten (20.68%) girls in the quantitative sample married as children. The results revealed that girls who had never attended school compared to those who had ever attended school were more likely to marry as children (OR, 3.01). Compared with girls in the lowest wealth quintile, girls in the middle (OR, 0.59), fourth (OR, 0.37) and highest (OR, 0.32) wealth quintiles were less likely to marry as children. From the qualitative data, the study identified poverty, teenage pregnancy, and cultural norms such as betrothal marriage, exchange of girls for marriage and pressure from significant others as the drivers of child marriage., Conclusions: The findings show that various socio-economic and cultural factors such as education, teenage pregnancy and poverty influence child marriage. Hence, efforts to curb child marriage should be geared towards retention of girls in school, curbing teenage pregnancy, empowering girls economically, enforcing laws on child marriage in Ghana, as well as designing tailored advocacy programs to educate key stakeholders and adolescent girls on the consequences of child marriage. Additionally, there is the need to address socio-cultural norms/practices to help end child marriage.

Molecular doping is a crucial tool for controlling the charge-carrier concentration in organic semiconductors. Each dopant molecule is commonly thought to give rise to only one polaron, leading to a maximum of one donor:acceptor charge-transfer complex and hence an ionization efficiency of 100%. However, this theoretical limit is rarely achieved because of incomplete charge transfer and the presence of unreacted dopant. Here, we establish that common p-dopants can in fact accept two electrons per molecule from conjugated polymers with a low ionization energy. Each dopant molecule participates in two charge-transfer events, leading to the formation of dopant dianions and an ionization efficiency of up to 200%. Furthermore, we show that the resulting integer charge-transfer complex can dissociate with an efficiency of up to 170%. The concept of double doping introduced here may allow the dopant fraction required to optimize charge conduction to be halved.

In order to discover the potential genetic risks associated with recurrent pregnancy loss (RPL), this meta-analysis was conducted to assess the association between CYP1A1 gene polymorphism and RPL. Studies were retrieved from the databases PubMed, Embase, HuGENet, and CNKI. Four models were then applied. Seven studies, including three datasets for the rs1048943 and five for the rs4646903 single-nucleotide polymorphism (SNP), were included in this analysis, involving 613 cases and 398 controls for the rs1048943; and 864 cases and 842 controls for the rs4646903 SNP. After comprehensive analysis, we found that rs4646903 was significantly associated with RPL [recessive (OR = 1.72, 95%CI: 1.13-2.61); codominant (CC vs TT; OR = 1.74, 95%CI: 1.12-2.71), (CC vs CT; OR = 1.67, 95%CI: 1.07-2.62) and allele analysis (OR = 1.27, 95%CI: 1.07-1.50)]. In the following subgroup analysis, a positive association was also discovered among people of Asian descent, especially South Asians. However, there was no obvious association between rs1048943 and RPL. In summary, our results suggest that CYP1A1 gene polymorphism (particularly for rs4646903) might be associated with RPL risk, especially among South Asians. Further studies are required to confirm this association., (© 2017 John Wiley & Sons Ltd/University College London.)