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Fundamental knowledge about the processes that control the functioning of the biophysical workings of ecosystems has expanded exponentially since the late 1960s. Scientists, then, had only primitive knowledge about C, N, P, S, and H2O cycles; plant, animal, and soil microbial interactions and dynamics; and land, atmosphere, and water interactions. With the advent of systems ecology paradigm (SEP) and the explosion of technologies supporting field and laboratory research, scientists throughout the world were able to assemble the knowledge base known today as ecosystem science. This chapter describes, through the eyes of scientists associated with the Natural Resource Ecology Laboratory (NREL) at Colorado State University (CSU), the evolution of the SEP in discovering how biophysical systems at small scales (ecological sites, landscapes) function as systems. The NREL and CSU are epicenters of the development of ecosystem science. Later, that knowledge, including humans as components of ecosystems, has been applied to small regions, regions, and the globe. Many research results that have formed the foundation for ecosystem science and management of natural resources, terrestrial environments, and its waters are described in this chapter. Throughout are direct and implicit references to the vital collaborations with the global network of ecosystem scientists.
This SHEA white paper identifies knowledge gaps and challenges in healthcare epidemiology research related to COVID-19 with a focus on core principles of healthcare epidemiology. These gaps, revealed during the worst phases of the COVID-19 pandemic, are described in 10 sections: epidemiology, outbreak investigation, surveillance, isolation precaution practices, personal protective equipment (PPE), environmental contamination and disinfection, drug and supply shortages, antimicrobial stewardship, healthcare personnel (HCP) occupational safety, and return to work policies. Each section highlights three critical healthcare epidemiology research questions with detailed description provided in supplemental materials. This research agenda calls for translational studies from laboratory-based basic science research to well-designed, large-scale studies and health outcomes research. Research gaps and challenges related to nursing homes and social disparities are included. Collaborations across various disciplines, expertise and across diverse geographic locations will be critical.
An impairment in recognizing distress is implicated in the development and severity of antisocial behavior. It has been hypothesized that a lack of attention to the eyes plays a role, but supporting evidence is limited. We developed a computerized training to improve emotion recognition in children and examined the role of eye gaze before and after training. Children referred into an intervention program to prevent antisocial outcomes completed an emotion recognition task with concurrent eye tracking. Those with emotion recognition impairments (n = 54, mean age: 8.72 years, 78% male) completed the training, while others (n = 38, mean age: 8.95 years, 84% male) continued with their usual interventions. Emotion recognition and eye gaze were reassessed in all children 8 weeks later. Impaired negative emotion recognition was significantly related to severity of behavioral problems at pretest. Children who completed the training significantly improved in emotion recognition; eye gaze did not contribute to impairment or improvement in emotion recognition. This study confirms the role of emotion recognition in severity of disruptive behavior and shows that a targeted intervention can quickly improve emotion impairments. The training works by improving children's ability to appraise emotional stimuli rather than by influencing their visual attention.
There is compelling evidence for gradient effects of household income on school readiness. Potential mechanisms are described, yet the growth curve trajectory of maternal mental health in a child's early life has not been thoroughly investigated. We aimed to examine the relationships between household incomes, maternal mental health trajectories from antenatal to the postnatal period, and school readiness.
Prospective data from 505 mother–child dyads in a birth cohort in Singapore were used, including household income, repeated measures of maternal mental health from pregnancy to 2-years postpartum, and a range of child behavioural, socio-emotional and cognitive outcomes from 2 to 6 years of age. Antenatal mental health and its trajectory were tested as mediators in the latent growth curve models.
Household income was a robust predictor of antenatal maternal mental health and all child outcomes. Between children from the bottom and top household income quartiles, four dimensions of school readiness skills differed by a range of 0.52 (95% Cl: 0.23, 0.67) to 1.21 s.d. (95% CI: 1.02, 1.40). Thirty-eight percent of pregnant mothers in this cohort were found to have perinatal depressive and anxiety symptoms in the subclinical and clinical ranges. Poorer school readiness skills were found in children of these mothers when compared to those of mothers with little or no symptoms. After adjustment of unmeasured confounding on the indirect effect, antenatal maternal mental health provided a robust mediating path between household income and multiple school readiness outcomes (χ2 126.05, df 63, p < 0.001; RMSEA = 0.031, CFI = 0.980, SRMR = 0.034).
Pregnant mothers with mental health symptoms, particularly those from economically-challenged households, are potential targets for intervention to level the playing field of their children.
Treatment for major depressive disorder (MDD) is imprecise and often involves trial-and-error to determine the most effective approach. To facilitate optimal treatment selection and inform timely adjustment, the current study investigated whether neurocognitive variables could predict an antidepressant response in a treatment-specific manner.
In the two-stage Establishing Moderators and Biosignatures of Antidepressant Response for Clinical Care (EMBARC) trial, outpatients with non-psychotic recurrent MDD were first randomized to an 8-week course of sertraline selective serotonin reuptake inhibitor or placebo. Behavioral measures of reward responsiveness, cognitive control, verbal fluency, psychomotor, and cognitive processing speeds were collected at baseline and week 1. Treatment responders then continued on another 8-week course of the same medication, whereas non-responders to sertraline or placebo were crossed-over under double-blinded conditions to bupropion noradrenaline/dopamine reuptake inhibitor or sertraline, respectively. Hamilton Rating for Depression scores were also assessed at baseline, weeks 8, and 16.
Greater improvements in psychomotor and cognitive processing speeds within the first week, as well as better pretreatment performance in these domains, were specifically associated with higher likelihood of response to placebo. Moreover, better reward responsiveness, poorer cognitive control and greater verbal fluency were associated with greater likelihood of response to bupropion in patients who previously failed to respond to sertraline.
These exploratory results warrant further scrutiny, but demonstrate that quick and non-invasive behavioral tests may have substantial clinical value in predicting antidepressant treatment response.
Pilot randomized double-blind-controlled trial of repetitive paired associative stimulation (rPAS), a paradigm that combines transcranial magnetic stimulation (TMS) of the dorsolateral prefrontal cortex (DLPFC) with peripheral median nerve stimulation.
To study the impact of rPAS on DLPFC plasticity and working memory performance in Alzheimer’s disease (AD).
Thirty-two patients with AD (females = 16), mean (SD) age = 76.4 (6.3) years were randomized 1:1 to receive a 2-week (5 days/week) course of active or control rPAS. DLPFC plasticity was assessed using single session PAS combined with electroencephalography (EEG) at baseline and on days 1, 7, and 14 post-rPAS. Working memory and theta–gamma coupling were assessed at the same time points using the N-back task and EEG.
There were no significant differences between the active and control rPAS groups on DLPFC plasticity or working memory performance after the rPAS intervention. There were significant main effects of time on DLPFC plasticity, working memory, and theta–gamma coupling, only for the active rPAS group. Further, on post hoc within-group analyses done to generate hypotheses for future research, as compared to baseline, only the rPAS group improved on post-rPAS day 1 on all three indices. Finally, there was a positive correlation between working memory performance and theta–gamma coupling.
This study did not show a beneficial effect of rPAS for DLPFC plasticity or working memory in AD. However, post hoc analyses showed promising results favoring rPAS and supporting further research on this topic. (Clinicaltrials.gov-NCT01847586)
Background: Automated testing instruments (ATIs) are commonly used by clinical microbiology laboratories to perform antimicrobial susceptibility testing (AST), whereas public health laboratories may use established reference methods such as broth microdilution (BMD). We investigated discrepancies in carbapenem minimum inhibitory concentrations (MICs) among Enterobacteriaceae tested by clinical laboratory ATIs and by reference BMD at the CDC. Methods: During 2016–2018, we conducted laboratory- and population-based surveillance for carbapenem-resistant Enterobacteriaceae (CRE) through the CDC Emerging Infections Program (EIP) sites (10 sites by 2018). We defined an incident case as the first isolation of Enterobacter spp (E. cloacae complex or E. aerogenes), Escherichia coli, Klebsiella pneumoniae, K. oxytoca, or K. variicola resistant to doripenem, ertapenem, imipenem, or meropenem from normally sterile sites or urine identified from a resident of the EIP catchment area in a 30-day period. Cases had isolates that were determined to be carbapenem-resistant by clinical laboratory ATI MICs (MicroScan, BD Phoenix, or VITEK 2) or by other methods, using current Clinical and Laboratory Standards Institute (CLSI) criteria. A convenience sample of these isolates was tested by reference BMD at the CDC according to CLSI guidelines. Results: Overall, 1,787 isolates from 112 clinical laboratories were tested by BMD at the CDC. Of these, clinical laboratory ATI MIC results were available for 1,638 (91.7%); 855 (52.2%) from 71 clinical laboratories did not confirm as CRE at the CDC. Nonconfirming isolates were tested on either a MicroScan (235 of 462; 50.9%), BD Phoenix (249 of 411; 60.6%), or VITEK 2 (371 of 765; 48.5%). Lack of confirmation was most common among E. coli (62.2% of E. coli isolates tested) and Enterobacter spp (61.4% of Enterobacter isolates tested) (Fig. 1A), and among isolates testing resistant to ertapenem by the clinical laboratory ATI (52.1%, Fig. 1B). Of the 1,388 isolates resistant to ertapenem in the clinical laboratory, 1,006 (72.5%) were resistant only to ertapenem. Of the 855 nonconfirming isolates, 638 (74.6%) were resistant only to ertapenem based on clinical laboratory ATI MICs. Conclusions: Nonconfirming isolates were widespread across laboratories and ATIs. Lack of confirmation was most common among E. coli and Enterobacter spp. Among nonconfirming isolates, most were resistant only to ertapenem. These findings may suggest that ATIs overcall resistance to ertapenem or that isolate transport and storage conditions affect ertapenem resistance. Further investigation into this lack of confirmation is needed, and CRE case identification in public health surveillance may need to account for this phenomenon.
Impairments in social cognition contribute significantly to disability in schizophrenia patients (SzP). Perception of facial expressions is critical for social cognition. Intact perception requires an individual to visually scan a complex dynamic social scene for transiently moving facial expressions that may be relevant for understanding the scene. The relationship of visual scanning for these facial expressions and social cognition remains unknown.
In 39 SzP and 27 healthy controls (HC), we used eye-tracking to examine the relationship between performance on The Awareness of Social Inference Test (TASIT), which tests social cognition using naturalistic video clips of social situations, and visual scanning, measuring each individual's relative to the mean of HC. We then examined the relationship of visual scanning to the specific visual features (motion, contrast, luminance, faces) within the video clips.
TASIT performance was significantly impaired in SzP for trials involving sarcasm (p < 10−5). Visual scanning was significantly more variable in SzP than HC (p < 10−6), and predicted TASIT performance in HC (p = 0.02) but not SzP (p = 0.91), differing significantly between groups (p = 0.04). During the visual scanning, SzP were less likely to be viewing faces (p = 0.0001) and less likely to saccade to facial motion in peripheral vision (p = 0.008).
SzP show highly significant deficits in the use of visual scanning of naturalistic social scenes to inform social cognition. Alterations in visual scanning patterns may originate from impaired processing of facial motion within peripheral vision. Overall, these results highlight the utility of naturalistic stimuli in the study of social cognition deficits in schizophrenia.
Major depressive disorder (MDD) is associated with increased allostatic load (AL; a measure of physiological costs of repeated/chronic stress-responding) and metabolic dysregulation (MetD; a measure of metabolic health and precursor to many medical illnesses). Though AL and MetD are associated with poor somatic health outcomes, little is known regarding their relationship with antidepressant-treatment outcomes.
We determined pre-treatment AL and MetD in 67 healthy controls and 34 unmedicated, medically healthy MDD subjects. Following this, MDD subjects completed 8-weeks of open-label selective serotonin reuptake inhibitor (SSRI) antidepressant treatment and were categorized as ‘Responders’ (⩾50% improvement in depression severity ratings) or ‘Non-responders’ (<50% improvement). Logistic and linear regressions were performed to determine if pre-treatment AL or MetD scores predicted SSRI-response. Secondary analyses examined cross-sectional differences between MDD and control groups.
Pre-treatment AL and MetD scores significantly predicted continuous antidepressant response (i.e. absolute decreases in depression severity ratings) (p = 0.012 and 0.014, respectively), as well as post-treatment status as a Responder or Non-responder (p = 0.022 and 0.040, respectively), such that higher pre-treatment AL and MetD were associated with poorer SSRI-treatment outcomes. Pre-treatment AL and MetD of Responders were similar to Controls, while those of Non-responders were significantly higher than both Responders (p = 0.025 and 0.033, respectively) and Controls (p = 0.039 and 0.001, respectively).
These preliminary findings suggest that indices of metabolic and hypothalamic-pituitary-adrenal-axis dysregulation are associated with poorer SSRI-treatment response. To our knowledge, this is the first study to demonstrate that these markers of medical disease risk also predict poorer antidepressant outcomes.
This chapter focuses on advancements in the understanding of personality pathology gained from structural and functional neuroimaging studies. It draws from the literature on the most widely researched personality disorders including schizotypal, borderline, and antisocial personality disorder. Prominent findings in schizotypal personality disorder include abnormalities in temporal and frontal lobe volumes, decreased structural connectivity of temporal lobe regions, and inefficient recruitment of brain areas during task performance. In borderline personality disorder, neuroimaging findings are characterized by aberrant volume and activity of limbic and prefrontal brain areas that suggest diminished top-down control of affective responsivity. Studies in antisocial personality disorder reveal reduced volume in prefrontal and temporal lobe structures, white matter structure compromise, and altered brain network functional connectivity. Significant challenges in studying this complex population and limitations of current methodology are discussed. Suggestions for future directions of research in this field are provided.
This rejoinder uses the neuroimaging literature on affect regulation to exemplify how integration of complementary methods suggested by the commentaries could advance neurobiological understanding of personality disorders. It illustrates progressive insights gained from incorporating multiple sources of evidence including neuroimaging, genetics, and behavioral data associated with affect regulation. It also demonstrates the use of brain pattern activation analysis in addition to studying individual regions of interest to better understand the complex relationships between biological genotype, brain activity, and behavioral phenotype. The ways in which neuroimaging can serve as an endophenotype to bridge the gap between genes and distant phenotypes are highlighted.
Cognitive Behaviour Therapy (CBT) is an effective psychological intervention for children and young people with anxiety disorders (James et al, 2013). This has led to interest in whether CBT programmes can be widely provided in schools to prevent or ameliorate anxiety symptoms in children.
Results from school based anxiety prevention trials are encouraging (Neil & Christensen 2009; Fisak, Richard, Mann 2011). Before the widespread use of school based preventive programmes can be advocated methodologically robust evaluations are required to demonstrate that they are effective when transported to everyday settings.
To undertake a pragmatic randomised controlled trial (RCT) of a universal school based CBT programme (Friends for Life) for children aged 9-10 years of age .
Three arm RCT comparing Friends for Life delivered by trained health or school leaders with usual school provision (Stallard et al,2012). Primary outcome the Revised Child Anxiety and Depression Scale (RCADS) at 12 month follow-up.
A total of 1362 children from 40 schools participated with 1257 (92%) being re-assessed at follow-up. There was a difference in adjusted mean child report RCADS scores for health-led versus school-led FRIENDS (−3.94, 95%CI −6.41 to −1.47) and health-led FRIENDS versus usual school provision (2.66, 95%CI −5.22 to −0.09). Health-led CBT resulted in greater reductions in symptoms of anxiety than the other two arms (Stallard et al 2014),
Our pragmatic trial demonstrates that universally delivered anxiety prevention programmes can be effective when transported into schools. However, effectiveness varies depending upon who delivers them.
When cognitive decline (CD) is present, attention is one of the impaired mental functions. CD is also associated with anxious/depressive symptoms and with some demographic variables, particularly, age.
Investigate the associations between selective attention (Stroop Test: Stroop_Word, Stroop_Color, Difference between Stroop_Word and Stroop_Color, Stroop Ratio_Word, Stroop Ratio_Color and Difference between Stroop Ratio_Word and Stroop Ratio_ Color) and CD (Montreal Cognitive Assessment/MoCA) in institutionalized elders; explore the predictive value of Stroop variables for CD, controlling anxious/depressive symptoms and sociodemographic variables.
140 institutionalized elders (mean age, M = 78.4, SD = 7.48, range = 60-97) voluntarily answered to sociodemographic questions, the MoCA, the Geriatric Anxiety Inventory/GAI, the Geriatric Depression Scale/GDS and Stroop test.
73 elders (52, 1%) had CD. Dichotomized MoCA was associated with Stroop_Word, Stroop_Color, Stroop Ratio_Word, Stroop Ratio_Color, GDS and the sociodemographic variable schooling × profession. Age and education were not tested, since MoCA was stratified according to those variables. GDS, Stroop Ratio_Word and Stroop Ratio_Color showed to predict CD.
There was an association between Stroop_Word, Stroop_Color, Stroop Ratio_Word and Stroop Ratio_Color and CD, confirming that selective attention is smaller when the elderly reveal CD. GDS and CD were, also, associated. However, there was no association between MoCA dichotomized and differences between the correct answers (Stroop_Word and Stroop_Color) and Ratios (Stroop Ratio_Word and Stroop Ratio_Color). Selective attention and depressive symptoms predicted CD. It would be important to intervene through cognitive rehabilitation with the elders to improve their attention.
Little is known about who would benefit from Internet-based personalised nutrition (PN) interventions. This study aimed to evaluate the characteristics of participants who achieved greatest improvements (i.e. benefit) in diet, adiposity and biomarkers following an Internet-based PN intervention. Adults (n 1607) from seven European countries were recruited into a 6-month, randomised controlled trial (Food4Me) and randomised to receive conventional dietary advice (control) or PN advice. Information on dietary intake, adiposity, physical activity (PA), blood biomarkers and participant characteristics was collected at baseline and month 6. Benefit from the intervention was defined as ≥5 % change in the primary outcome (Healthy Eating Index) and secondary outcomes (waist circumference and BMI, PA, sedentary time and plasma concentrations of cholesterol, carotenoids and omega-3 index) at month 6. For our primary outcome, benefit from the intervention was greater in older participants, women and participants with lower HEI scores at baseline. Benefit was greater for individuals reporting greater self-efficacy for ‘sticking to healthful foods’ and who ‘felt weird if [they] didn’t eat healthily’. Participants benefited more if they reported wanting to improve their health and well-being. The characteristics of individuals benefiting did not differ by other demographic, health-related, anthropometric or genotypic characteristics. Findings were similar for secondary outcomes. These findings have implications for the design of more effective future PN intervention studies and for tailored nutritional advice in public health and clinical settings.
Shared patient–clinician decision-making is central to choosing between medical treatments. Decision support tools can have an important role to play in these decisions. We developed a decision support tool for deciding between nonsurgical treatment and surgical total knee replacement for patients with severe knee osteoarthritis. The tool aims to provide likely outcomes of alternative treatments based on predictive models using patient-specific characteristics. To make those models relevant to patients with knee osteoarthritis and their clinicians, we involved patients, family members, patient advocates, clinicians, and researchers as stakeholders in creating the models.
Stakeholders were recruited through local arthritis research, advocacy, and clinical organizations. After being provided with brief methodological education sessions, stakeholder views were solicited through quarterly patient or clinician stakeholder panel meetings and incorporated into all aspects of the project.
Participating in each aspect of the research from determining the outcomes of interest to providing input on the design of the user interface displaying outcome predications, 86% (12/14) of stakeholders remained engaged throughout the project. Stakeholder engagement ensured that the prediction models that form the basis of the Knee Osteoarthritis Mathematical Equipoise Tool and its user interface were relevant for patient–clinician shared decision-making.
Methodological research has the opportunity to benefit from stakeholder engagement by ensuring that the perspectives of those most impacted by the results are involved in study design and conduct. While additional planning and investments in maintaining stakeholder knowledge and trust may be needed, they are offset by the valuable insights gained.
Aging is associated with numerous stressors that negatively impact older adults’ well-being. Resilience improves ability to cope with stressors and can be enhanced in older adults. Senior housing communities are promising settings to deliver positive psychiatry interventions due to rising resident populations and potential impact of delivering interventions directly in the community. However, few intervention studies have been conducted in these communities. We present a pragmatic stepped-wedge trial of a novel psychological group intervention intended to improve resilience among older adults in senior housing communities.
A pragmatic modified stepped-wedge trial design.
Five senior housing communities in three states in the US.
Eighty-nine adults over age 60 years residing in independent living sector of senior housing communities.
Raise Your Resilience, a manualized 1-month group intervention that incorporated savoring, gratitude, and engagement in value-based activities, administered by unlicensed residential staff trained by researchers. There was a 1-month control period and a 3-month post-intervention follow-up.
Validated self-report measures of resilience, perceived stress, well-being, and wisdom collected at months 0 (baseline), 1 (pre-intervention), 2 (post-intervention), and 5 (follow-up).
Treatment adherence and satisfaction were high. Compared to the control period, perceived stress and wisdom improved from pre-intervention to post-intervention, while resilience improved from pre-intervention to follow-up. Effect sizes were small in this sample, which had relatively high baseline resilience. Physical and mental well-being did not improve significantly, and no significant moderators of change in resilience were identified.
This study demonstrates feasibility of conducting pragmatic intervention trials in senior housing communities. The intervention resulted in significant improvement in several measures despite ceiling effects. The study included several features that suggest high potential for its implementation and dissemination across similar communities nationally. Future studies are warranted, particularly in samples with lower baseline resilience or in assisted living facilities.
Smoking was one of the biggest preventable killers of the 20th century, and it continues to cause the death of millions across the globe. The rapid growth of the e-cigarette market in the last 10 years and the claims that it is a safer form of smoking, and can help with smoking cessation, have led to questions being raised on their possible impact to society, the health of the population and the insurance industry. Recent media attention around the possible health implications of e-cigarette use has also ensured that this topic remains in the public eye. The e-cigarette working party was initiated by the Institute and Faculty of Actuaries’ Health and Care Research Sub-Committee in July 2016, with the primary objective of understanding the impact of e-cigarettes on life and health insurance. In this paper, we have looked at all areas of e-cigarette usage and how it relates to insurance in the UK market. In particular, we have covered the potential risks and benefits of switching to e-cigarettes, the results of studies that have been published, the potential impact on underwriting and claims processes and the potential impact on pricing (based on what modelling is possible with the data available). Research in this area is still in its infancy and data are not yet mature, which makes predicting the long-term impact of e-cigarette smoking extremely challenging, for example, there are no studies that directly measure the mortality or morbidity impact of long-term e-cigarette use and so we have had to consider studies that consider more immediate health impacts or look more simply at the constituents of the output of an e-cigarette and compare them to that of a cigarette. The data issue is further compounded by the findings of studies and the advice of national health authorities often being conflicting. For example, while National Health Service England has publicly stated that it supports the growth of e-cigarette usage as an aid to reduce traditional smoking behaviour, the US Food and Drug Administration has been much more vocal in highlighting the perceived dangers of this new form of smoking. Users’ behaviour also adds complexity, as dual use (using both e-cigarettes and cigarettes) is seen in a high percentage of users and relapse rates back to cigarette smoking are currently unknown. Having talked to a number of experts in the field, we have discovered that there is certainly not a common view on risk. We have heard from experts who have significant concerns but also to experts who do believe that e-cigarettes are far safer than tobacco. We have purposefully considered conflicting evidence and have consulted with various parties so we can present differing points of view, thereby ensuring a balanced, unbiased and fair picture of our findings is presented. The evidence we have reviewed does suggest that e-cigarettes are a safer alternative to traditional smoking, but not as safe as non-smoking. There are no large, peer-reviewed, long-term studies yet available to understand the true impact of a switch to e-cigarette use, so currently we are unable to say where on the risk spectrum between cigarette smoking and life-time non-smoking it lies. We do not yet understand if the benefits seen in the studies completed so far will reduce the risk in the long term or whether other health risks will come to light following more prolonged use and study. This, coupled with concerns with the high proportion of dual use of cigarettes and e-cigarettes, relapse rates and the recent growth in medical problems linked with e-cigarette use, means that we need to wait for experience to emerge fully before firm conclusions can be drawn. Although we have presented a view, it is vitally important that our industry continues to monitor developments in this area and fully considers what next steps and future actions may be required to ensure our position reflects the potential benefits and risks that e-cigarette use may bring. We feel that the time is right for a body such as the IFoA to analyse the feasibility of collecting the necessary data through the Continuous Mortality Investigation that would allow us to better analyse the experience that is emerging.
We report a significant advance in thermally insulating transparent materials: silica-based monoliths with controlled porosity which exhibit the transparency of windows in combination with a thermal conductivity comparable to aerogels.
The lack of transparent, thermally insulating windows leads to substantial heat loss in commercial and residential buildings, which accounts for ~4.2% of primary US energy consumption annually. The present study provides a potential solution to this problem by demonstrating that ambiently dried silica aerogel monoliths, i.e., ambigels, can simultaneously achieve high optical transparency and low thermal conductivity without supercritical drying. A combination of tetraethoxysilane, methyltriethoxysilane, and post-gelation surface modification precursors were used to synthesize ambiently dried materials with varying pore fractions and pore sizes. By controlling the synthesis and processing conditions, 0.5–3 mm thick mesoporous monoliths with transmittance >95% and a thermal conductivity of 0.04 W/(m K) were produced. A narrow pore size distribution, <15 nm, led to the excellent transparency and low haze, while porosity in excess of 80% resulted in low thermal conductivity. A thermal transport model considering fractal dimension and phonon-boundary scattering is proposed to explain the low effective thermal conductivity measured. This work offers new insights into the design of transparent, energy saving windows.