Robust Higher-Order Hamiltonian Engineering for Quantum Sensing with Strongly Interacting Systems.

Dynamical decoupling techniques constitute an integral part of many quantum sensing platforms, often leading to orders-of-magnitude improvements in coherence time and sensitivity. Most ac sensing sequences involve a periodic echolike structure, in which the target signal is synchronized with the echo period. We show that for strongly interacting systems, this construction leads to a fundamental sensitivity limit associated with imperfect interaction decoupling. We present a simple physical picture demonstrating the origin of this limitation, and further formalize these considerations in terms of concise higher-order decoupling rules. We then show how these limitations can be surpassed by identifying a novel sequence building block, in which the signal period matches twice the echo period. Using these decoupling rules and the resulting sequence building block, we experimentally demonstrate significant improvements in dynamical decoupling timescales and magnetic field sensitivity, opening the door for new applications in quantum sensing and quantum many-body physics.

Effects of the in ovo injection of an Escherichia coli vaccine on the hatchability and quality characteristics of commercial layer hatchlings.

In the commercial egg industry, avian pathogenic Escherichia coli (APEC) can lead to significant economic loss. The Poulvac E. coli vaccine (PECV) is a commercially available attenuated live vaccine commonly applied via spray or drinking water to protect against losses associated with colibacillosis. The PECV has not been tested in layer hatching eggs using in ovo injection. Therefore, the purpose of this experiment was to determine the effects of injecting 50 µL of different doses of the PECV into Hy-Line W-36-layer hatching eggs on the hatchability and quality characteristics of hatchlings. At 18 d of incubation (DOI), treatments included 1 noninjected and 1 diluent-injected control. Furthermore, PECV treatments included a full dose (4.4 × 108E. coli CFU) or serial dilutions of the full dose to produce 4.4 × 106, 4.4 × 104, or 4.4 × 102 CFU doses of E. coli. In ovo injections targeted the amnion. Percent hatchability of live embryonated eggs (HI), percent residue eggs, hatchling mortality, and female chick whole and yolk-free BW, relative yolk sac weight, and body length were among the variables examined. Treatment significantly (P < 0.0001) affected HI, with HI being highest in the control groups (97.3% in the noninjected and 94.2% in the diluent-injected), and with HI values being 89.0, 88.9, 84.4, and 71.2% in the 4.4 × 102, 4.4 × 104, 4.4 × 106, and 4.4 × 108 CFU E. coli dose treatments, respectively. The percentage of live embryos that did not complete hatch but that pipped internally (P = 0.024) or externally (P < 0.0001) were significantly affected by treatment, with percentages being highest in the 4.4 × 108 CFU treatment. Female chick body length was significantly (P < 0.0001) affected by treatment and was longer in both control groups and in the 1 × 102 CFU E. coli treatment in comparison to all other treatments. Yolk-free female chick BW was significantly (P = 0.034) affected by treatment and was lower in the 4.4 × 106 CFU and 4.4 × 108 CFU treatments when compared to the diluent-injected control group. An increase in the E. coli concentration administered in the amnion of embryonated layer hatching eggs at 18 DOI decreased hatch success and female chick yolk-free BW and body length.

Controlling Local Thermalization Dynamics in a Floquet-Engineered Dipolar Ensemble.

Understanding the microscopic mechanisms of thermalization in closed quantum systems is among the key challenges in modern quantum many-body physics. We demonstrate a method to probe local thermalization in a large-scale many-body system by exploiting its inherent disorder and use this to uncover the thermalization mechanisms in a three-dimensional, dipolar-interacting spin system with tunable interactions. Utilizing advanced Hamiltonian engineering techniques to explore a range of spin Hamiltonians, we observe a striking change in the characteristic shape and timescale of local correlation decay as we vary the engineered exchange anisotropy. We show that these observations originate from the system's intrinsic many-body dynamics and reveal the signatures of conservation laws within localized clusters of spins, which do not readily manifest using global probes. Our method provides an exquisite lens into the tunable nature of local thermalization dynamics and enables detailed studies of scrambling, thermalization, and hydrodynamics in strongly interacting quantum systems.

Memory of social experience affects female fecundity via perception of fly deposits.

BACKGROUND: Animals can exhibit remarkable reproductive plasticity in response to their social surroundings, with profound fitness consequences. The presence of same-sex conspecifics can signal current or future expected competition for resources or mates. Plastic responses to elevated sexual competition caused by exposure to same-sex individuals have been well-studied in males. However, much less is known about such plastic responses in females, whether this represents sexual or resource competition, or if it leads to changes in investment in mating behaviour and/or reproduction. Here, we used Drosophila melanogaster to measure the impact of experimentally varying female exposure to other females prior to mating on fecundity before and after mating. We then deployed physical and genetic methods to manipulate the perception of different social cues and sensory pathways and reveal the potential mechanisms involved. RESULTS: The results showed that females maintained in social isolation prior to mating were significantly more likely to retain unfertilised eggs before mating, but to show the opposite and lay significantly more fertilised eggs in the 24h after mating. More than 48h of exposure to other females was necessary for this social memory response to be expressed. Neither olfactory nor visual cues were involved in mediating fecundity plasticity-instead, the relevant cues were perceived through direct contact with the non-egg deposits left behind by other females. CONCLUSIONS: The results demonstrate that females show reproductive plasticity in response to their social surroundings and can carry this memory of their social experience forward through mating. Comparisons of our results with previous work show that the nature of female plastic reproductive responses and the cues they use differ markedly from those of males. The results emphasise the deep divergence in how each sex realises its reproductive success.

Genome sequencing reveals underdiagnosis of primary ciliary dyskinesia in bronchiectasis.

BACKGROUND: Bronchiectasis can result from infectious, genetic, immunological and allergic causes. 60-80% of cases are idiopathic, but a well-recognised genetic cause is the motile ciliopathy, primary ciliary dyskinesia (PCD). Diagnosis of PCD has management implications including addressing comorbidities, implementing genetic and fertility counselling and future access to PCD-specific treatments. Diagnostic testing can be complex; however, PCD genetic testing is moving rapidly from research into clinical diagnostics and would confirm the cause of bronchiectasis. METHODS: This observational study used genetic data from severe bronchiectasis patients recruited to the UK 100,000 Genomes Project and patients referred for gene panel testing within a tertiary respiratory hospital. Patients referred for genetic testing due to clinical suspicion of PCD were excluded from both analyses. Data were accessed from the British Thoracic Society audit, to investigate whether motile ciliopathies are underdiagnosed in people with bronchiectasis in the UK. RESULTS: Pathogenic or likely pathogenic variants were identified in motile ciliopathy genes in 17 (12%) out of 142 individuals by whole-genome sequencing. Similarly, in a single centre with access to pathological diagnostic facilities, 5-10% of patients received a PCD diagnosis by gene panel, often linked to normal/inconclusive nasal nitric oxide and cilia functional test results. In 4898 audited patients with bronchiectasis, <2% were tested for PCD and <1% received genetic testing. CONCLUSIONS: PCD is underdiagnosed as a cause of bronchiectasis. Increased uptake of genetic testing may help to identify bronchiectasis due to motile ciliopathies and ensure appropriate management.

Novel quantification of regional fossil fuel CO2 reductions during COVID-19 lockdowns using atmospheric oxygen measurements.

It is not currently possible to quantify regional-scale fossil fuel carbon dioxide (ffCO2) emissions with high accuracy in near real time. Existing atmospheric methods for separating ffCO2 from large natural carbon dioxide variations are constrained by sampling limitations, so that estimates of regional changes in ffCO2 emissions, such as those occurring in response to coronavirus disease 2019 (COVID-19) lockdowns, rely on indirect activity data. We present a method for quantifying regional signals of ffCO2 based on continuous atmospheric measurements of oxygen and carbon dioxide combined into the tracer "atmospheric potential oxygen" (APO). We detect and quantify ffCO2 reductions during 2020-2021 caused by the two U.K. COVID-19 lockdowns individually using APO data from Weybourne Atmospheric Observatory in the United Kingdom and a machine learning algorithm. Our APO-based assessment has near-real-time potential and provides high-frequency information that is in good agreement with the spread of ffCO2 emissions reductions from three independent lower-frequency U.K. estimates.

Cervical cerclage, pessary, or vaginal progesterone in high-risk pregnant women with short cervix: a randomized feasibility study.

Objective: To assess feasibility for a definitive randomized controlled trial (RCT) comparing three treatments for short cervix in a population at high risk for spontaneous preterm birth (sPTB) over a 1-year period.Design: Three arm, open label feasibility randomized clinical study.Methods: Women with singleton pregnancy with risk factors for sPTB (history of sPTB or prelabor premature rupture of membranes (PPROM) <34 weeks or significant cervical surgery), and short cervix on transvaginal ultrasound scan detected between 16+0 and 24+6 weeks gestation were randomized to receive either cervical cerclage, vaginal pessary, or vaginal progesterone 200 mg nocte. Pregnancy outcomes and treatment costs were collected from hospital records, NHS Reference costs, and British National Formulary costs.Main outcome measures: Feasibility targets were defined as (i) at least 55% of eligible women randomized; (ii) maximum 5% failure to adhere to the protocol per arm; (iii) maximum 5% loss to short-term follow-up.Results: Of 417 women screened between October 2015 and 2016, 25 (6%) were eligible for trial inclusion, of whom 18 (72%) agreed to participate at the rate 0.75 participants/site/month. Adherence to protocol was 100% in pessary and cerclage arms and 80% in vaginal progesterone arm (95% CI 24-100%). No participants were lost to follow up. Cost of interventions accounted for 6% (95% CI 2-10%) of overall health care expenditure.Conclusions: A definitive clinical trial comparing treatments for prevention of sPTB in high-risk women with short cervix is feasible but will be challenging due to small numbers of eligible participants.

Effects of dietary Original XPC on selected blood variables in layer pullets challenged with Mycoplasma gallisepticum,.

Effects of dietary Original XPC (XPC) on 17 selected blood variables in commercial layer pullets challenged with the virulent, low-passage R strain of Mycoplasma gallisepticum (RlowMG) were investigated. Hy-Line W-36 pullets sourced from M. gallisepticum-clean layer breeders were fed a basal diet with XPC (1.25 kg/metric ton) or without from hatch until 12 wk of age (woa). At 8 and 10 woa, half of the birds in each dietary treatment were challenged with RlowMG. Blood samples were taken immediately before the initial RlowMG challenge at 8 woa and again at 12 woa (4 wk after challenge). At 8 woa, blood pH was lower and glucose concentration was higher in the preassigned challenge treatment groups. At 12 woa, the concentration of oxygen dissolved in the blood was significantly lower in the RlowMG-challenged group than the unchallenged group of birds regardless of dietary treatment. The RlowMG challenge significantly increased blood carbon dioxide partial pressure, calcium, sodium, anion gap, osmolality, glucose, and corticosterone levels but significantly decreased blood oxygen partial pressure, oxyhemoglobin concentration, concentration of oxygen dissolved in the blood, chloride, and pH levels. Because blood pH and glucose concentration at 8 woa were examined before challenge, their baseline values were biased with respect to challenge treatment before treatment was applied. However, the lack of a significant main effect due to diet at 8 woa for blood pH and glucose concentration, along with the other 15 blood variables, indicate that the baseline data with respect to dietary treatment were unbiased, allowing for real dietary effects to be accurately assessed. In conclusion, layer pullets challenged with RlowMG undergo a stress response associated with changes in various physiological blood variables, and a decrease in pH and increase in carbon dioxide partial pressure, in association with a lack of change in bicarbonate, indicates that the stress response caused by the RlowMG challenge was associated with respiratory acidosis. Nevertheless, feeding XPC did not influence the effects of challenge treatment on these postchallenge physiological blood values.

Tapping into Community Resiliency in Rural Adolescent Pregnancy Prevention: An Implementation Sciences Approach.

Although rural youth experience marked inequities in adolescent pregnancy, there is little guidance for implementing evidence-based programs (EBPs) in rural settings. When implementation occurs in rural communities, it frequently focuses on deficits, rather than strengths or capacity for growth. Using the consolidated framework for implementation research (CFIR), we describe a resiliency-focused implementation of two middle school EBPs in rural Midwestern communities, including the intervention, outer and inner settings, individuals, implementation processes and preliminary outcomes. Data included program staff interviews, feedback from local partners, community meetings notes, and participant surveys. Using the CFIR, we describe the engagement of rural communities themselves in a resilience-based implementation of adolescent pregnancy prevention EPBs. Communities self-described as rural, traditional and religious. They identified adolescent pregnancy, substance use, and academic success as priorities. To address infrastructure needs and build on local strengths, funds were used to hire local partners to implement the program. As small communities, stakeholders were closely networked and wanted to address local needs. Local partners selected the EBP based upon community values and priorities. Champions, including local partner organizations and schools were locally based and were well connected. Intensive training of local staff and piloting with adaptation assured fidelity and sustainability, while increasing community implementation skills and comfort. In Clinton County, enrollment was 1946 with students receiving the program in 6th, 7th, and/or 8th grades. In Southern Indiana, 7275 students received the program once in either 6th, 7th, or 8th. We conclude that the CFIR can facilitate the implementation of a community resilience-focused adolescent pregnancy prevention intervention in rural communities.

Growth and humoral immune effects of dietary Original XPC in layer pullets challenged with Mycoplasma gallisepticum.

Effects of dietary Original XPC (XPC) in commercial layer pullets challenged with the virulent, low passage R strain of Mycoplasma gallisepticum (Rlow MG) were investigated. Hy-Line W-36 pullets sourced from MG-clean breeders were fed a basal diet with or without (CON) XPC (1.25 kg/metric ton) from hatch until 12 wk of age (woa). At 8 and 10 woa, half of the birds in each dietary treatment were challenged with Rlow MG. Body weight was recorded at 3, 8, and 12 woa, and ovary, ceca, and bursa weights were recorded at 3 and 12 woa. Blood samples were taken immediately before the initial Rlow MG challenge at 8 woa and again at 12 woa to test for IgM and IgG antibody production against MG. All birds were evaluated for MG lesion scores at 12 woa. Regardless of challenge, inclusion of XPC in the diet did not significantly alter BW at 3 or 8 woa or relative organ weights at 3 or 12 woa. However, at 12 woa, BW of XPC-fed birds, regardless of challenge was significantly (P = 0.0038) heavier than CON by 25.7 g. All birds tested negative for MG antibodies before the 8 woa challenge. Respective percentage serum plate agglutination and ELISA positive birds at 12 woa were 0 and 0% (CON, nonchallenged), 1.4 and 0% (XPC, nonchallenged), 100 and 47.2% (CON, challenged), and 100 and 50.0% (XPC, challenged). Diet did not significantly affect ELISA titers, but they were significantly (P < 0.0001) increased due to challenge. Furthermore, lesion scores were significantly higher for Rlow MG-challenged birds (P = 0.0012), and dietary treatment with XPC in challenged birds numerically reduced MG lesion scores from 0.278 to 0.194. In conclusion, although dietary XPC did not significantly alter the humoral immune response, antibody titer levels, or severity of MG lesions in layer pullets that were or were not challenged with Rlow MG, it led to an increase in their rate of growth through 12 woa.

Show Don't Tell: Diversity Dishonesty Harms Racial/Ethnic Minorities at Work.

Organizations aim to convey that they are diverse and inclusive, in part, to recruit racial minorities. We investigate a previously unexamined downside of this recruitment strategy: diversity dishonesty, that is, belief that an organization is falsely or incorrectly inflating its actual diversity. In four studies (total N = 871), we found that diversity dishonesty heightened minorities' concerns about fitting in, being authentic, and performing well at the organization. We also found that evidence-based cues (which "show" observers whether the organization has a positive or negative diversity climate), but not expressed cues (which "tell" observers about the organization's diversity), affect these expectations. Using correlational methodologies, Study 1 found these effects were pertinent to African American and Latinx participants' beliefs about their current workplaces, holding other diversity-related measures constant. Studies 2 to 4 used experimental methods to replicate these findings with African American participants, using a hypothetical workplace setting.

Only Yes Means Yes: Sexual Coercion in Rural Adolescent Relationships.

PURPOSE: Sexual consent is important to healthy relationships; however, sexual coercion is common. We examine modifiable risk and protective factors for sexual coercion among high school students in a rural community. METHODS: We surveyed 10th graders (N = 442) in a rural, Midwestern, low-to-middle income county before receiving an evidence-based sex education program. Sexual coercion was a single item, "has anyone you were dating or going out with forced you to do sexual things that you did not want to do?" We examined associations between sexual coercion and demographics, risk behaviors, sexual self-efficacy, controlling relationship behaviors, parent communication, and adverse childhood experiences. RESULTS: Approximately 22% of females and 8% of males reported experiencing sexual coercion at least once in their lifetime. Gender differences emerged in associated risk and protective factors, including sexual sex efficacy, controlling relationship behaviors, parent-adolescent communication about sex, and adverse childhood experiences. CONCLUSIONS: Sexual coercion is common among adolescents in rural communities. Prevention interventions should target modifiable risk and protective factors.

Foley catheter vs. oral misoprostol to induce labour among hypertensive women in India: a cost-consequence analysis alongside a clinical trial.

OBJECTIVE: To determine the effectiveness and economic impact of two methods for induction of labour in hypertensive women, in low-resource settings. DESIGN: Cost-consequence analysis of a previously reported multicentre, parallel, open-label randomised trial. SETTING & POPULATION: A total of 602 women with a live fetus, aged ≥18 years requiring delivery for pre-eclampsia or hypertension, in two public hospitals in Nagpur, India. METHODS: We performed a formal economic evaluation alongside the INFORM clinical trial. Women were randomised to receive transcervical Foley catheterisation or oral misoprostol 25 mcg. Healthcare expenditure was calculated using a provider-side microcosting approach. MAIN OUTCOME MEASURES: Rates of vaginal this delivery within 24 hours of induction, healthcare expenditure per completed treatment episode. RESULTS: Induction with oral misoprostol resulted in a (mean difference) $20.6USD reduction in healthcare expenditure [95% CI (-) $123.59 (-) $72.49], and improved achievement of vaginal delivery within 24 hours of induction, mean difference 10% [95% CI (-2 to 17.9%), P = 0.016]. Oxytocin administration time was reduced by 135.3 minutes [95% CI (84.4-186.2 minutes), P < 0.01] and caesarean sections by 9.1% [95% CI (1.1-17%), P = 0.025] for those receiving oral misoprostol. Following probabilistic sensitivity analysis, oral misoprostol was cost-saving in 63% of 5,000 bootstrap replications and achieved superior rates of vaginal delivery, delivery within 24 hours of induction and vaginal delivery within 24 hours of induction in 98.7%, 90.7%, and 99.4% of bootstrap simulations. Based on univariate threshold analysis, the unit price of oral misoprostol 25 mcg could feasibly increase 31-fold from $0.24 to $7.50 per 25 mcg tablet and remain cost-saving. CONCLUSION: Compared to Foley catheterisation for the induction of high-risk hypertensive women, oral misoprostol improves rates of vaginal delivery within 24 hours of induction and may also reduce costs. Additional research performed in other low-resource settings is required to determine their relative cost-effectiveness. TWEETABLE ABSTRACT: Oral misoprostol less costly and more effective than Foley catheter for labour induction in hypertension.

The Enright phenomenon. Stereoscopic distortion of perceived driving speed induced by monocular pupil dilation / Fenómeno Enright. Distorsión estereoscópica de la velocidad percibida al conducir, inducida mediante dilatación monocular de la pupila

Purpose: The Enright phenomenon describes the distortion in speed perception experienced by an observer looking sideways from a moving vehicle when viewing with interocular differences in retinal image brightness, usually induced by neutral density filters. We investigated whether the Enright phenomenon could be induced with monocular pupil dilation using tropicamide. Methods: We tested 17 visually normal young adults on a closed road driving circuit. Participants were asked to travel at Goal Speeds of 40km/h and 60km/h while looking sideways from the vehicle with: (I) both eyes with undilated pupils; (II) both eyes with dilated pupils; (III) with the leading eye only dilated; and (iv) the trailing eye only dilated. For each condition we recorded actual driving speed. Results: With the pupil of the leading eye dilated participants drove significantly faster (by an average of 3.8km/h) than with both eyes dilated (p=0.02); with the trailing eye dilated participants drove significantly slower (by an average of 3.2km/h) than with both eyes dilated (p<0.001). The speed, with the leading eye dilated, was faster by an average of 7km/h than with the trailing eye dilated (p<0.001). There was no significant difference between driving speeds when viewing with both eyes either dilated or undilated (p=0.322). Conclusions: Our results are the first to show a measurable change in driving behaviour following monocular pupil dilation and support predictions based on the Enright phenomenon (AU)

Objetivo: El fenómeno Enright describe la distorsión en la percepción de la velocidad experimentada por un observador que mira lateralmente desde un vehículo en movimiento, y la visión con diferencias interoculares en cuanto a luminosidad de la imagen en la retina, normalmente inducida por filtros de densidad neutra. Investigamos si el fenómeno Enright podría inducirse mediante dilatación monocular de la pupila utilizando tropicamida. Métodos: Realizamos pruebas a 17 adultos jóvenes con visión normal, en un circuito cerrado de conducción por carretera. Se solicitó a los participantes que viajaran a velocidades predefinidas de 40km/h y 60km/h mientras miraban a ambos lados del vehículo con: I) ambos ojos sin dilatación pupilar; II) ambos ojos con las pupilas dilatadas; III) dilatación únicamente en el ojo fijador; y IV) dilatación únicamente en el ojo no fijador. Registramos la velocidad real de conducción para cada situación. Resultados: Con la pupila del ojo fijador dilatada los participantes condujeron a una velocidad considerablemente superior (de 3,8km/h de media) que con ambos ojos dilatados (p=0,02); con la pupila del ojo no fijador dilatada los participantes condujeron a una velocidad considerablemente menor (de 3,2km/h de media) que con ambos ojos dilatados (p<0,001). Con el ojo fijador dilatado la velocidad fue superior, de 7km/h de media, a la velocidad con el ojo no fijador dilatado (p<0,001). No se produjo diferencia significativa entre las velocidades de conducción cuando miraban con ambos ojos, tanto estuvieran dilatadas las pupilas o no (p=0,322). Conclusiones: Nuestros resultados son los primeros que reflejan un cambio medible en el comportamiento conductor tras la dilatación monocular de la pupila, y respaldan las predicciones que se basan en el fenómeno Enright (AU)

Characterizing Chilean blue whale vocalizations with DTAGs: a test of using tag accelerometers for caller identification.

Vocal behavior of blue whales (Balaenoptera musculus) in the Gulf of Corcovado, Chile, was analysed using both audio and accelerometer data from digital acoustic recording tags (DTAGs). Over the course of three austral summers (2014, 2015 and 2016), seventeen tags were deployed, yielding 124 h of data. We report the occurrence of Southeast Pacific type 2 (SEP2) calls, which exhibit peak frequencies, durations and timing consistent with previous recordings made using towed and moored hydrophones. We also describe tonal downswept (D) calls, which have not been previously described for this population. As being able to accurately assign vocalizations to individual whales is fundamental for studying communication and for estimating population densities from call rates, we further examine the feasibility of using high-resolution DTAG accelerometers to identify low-frequency calls produced by tagged blue whales. We cross-correlated acoustic signals with simultaneous tri-axial accelerometer readings in order to analyse the phase match as well as the amplitude of accelerometer signals associated with low-frequency calls, which provides a quantitative method of determining if a call is associated with a detectable acceleration signal. Our results suggest that vocalizations from nearby individuals are also capable of registering accelerometer signals in the tagged whale's DTAG record. We cross-correlate acceleration vectors between calls to explore the possibility of using signature acceleration patterns associated with sounds produced within the tagged whale as a new method of identifying which accelerometer-detectable calls originate from the tagged animal.

Toxicity assessment of ash and dust from handmade gold jewelry manufacturing workshops in Bangladesh.

Traditionally, handmade gold jewelry played a very important role in the cultural heritage of Bangladesh. Goldsmiths still are partially using ancient manufacturing process with coal fire, candle flame blowing, and nitric and sulfuric acid treatments. Such process leads to the contamination of workplace with the dust of toxic metals, acidic vapors, and particles of different natures. To evaluate contamination by particulate matter (PM), the passive particle collectors were installed in different manufacturing units for a period of 85 days at Tanti Bazar, Dhaka, Bangladesh. The laser diffraction analysis of the samples collected at the soldering units showed significant amounts of particulates, both PM10 and PM 2.5, and also nanoparticles in both nucleation and accumulation mode. SEM/EDS analysis revealed partially melted micro blebs that contain a very high concentration of Fe along with Cu. The toxic elements were detected with ICP analysis and include higher concentrations of cadmium (Cd), chromium (Cr), lead (Pb), and arsenic (As). It is notable that detection of arsenic contamination was unexpected since raw materials used for jewelry making should not have any arsenic.

Spatio-temporal variation in click production rates of beaked whales: Implications for passive acoustic density estimation.

Passive acoustic monitoring has become an increasingly prevalent tool for estimating density of marine mammals, such as beaked whales, which vocalize often but are difficult to survey visually. Counts of acoustic cues (e.g., vocalizations), when corrected for detection probability, can be translated into animal density estimates by applying an individual cue production rate multiplier. It is essential to understand variation in these rates to avoid biased estimates. The most direct way to measure cue production rate is with animal-mounted acoustic recorders. This study utilized data from sound recording tags deployed on Blainville's (Mesoplodon densirostris, 19 deployments) and Cuvier's (Ziphius cavirostris, 16 deployments) beaked whales, in two locations per species, to explore spatial and temporal variation in click production rates. No spatial or temporal variation was detected within the average click production rate of Blainville's beaked whales when calculated over dive cycles (including silent periods between dives); however, spatial variation was detected when averaged only over vocal periods. Cuvier's beaked whales exhibited significant spatial and temporal variation in click production rates within vocal periods and when silent periods were included. This evidence of variation emphasizes the need to utilize appropriate cue production rates when estimating density from passive acoustic data.

Effect of 3D-Printed Microvascular Network Design on the Self-Healing Behavior of Cross-Linked Polymers.

This article describes the manufacturing procedure and the characterization of self-healing polymers based on embedded microvascular networks. The samples were realized by resin casting into water-soluble PVA molds, fabricated via 3D printing. This technology allowed us to exploit the 3D printers' ability to produce complex structures with high resolution for the creation of independent microchannels networks. The two reacting components of a two-part resin could be stored separately within the microstructure. The materials' self-healing ability resulted from their reaction when severe damage caused the healing liquids to leak out, wetting the sample cross section and diffusing one into the other. The mechanical properties of healed samples were investigated by means of uniaxial tensile tests and compared to those of undamaged samples. The effect of microchannel density and different network designs on self-healing efficiency was determined. The different microstructures used were characterized using computerized X-ray microtomography. The versatility of the fabrication technique presented in this work allows conversion of any water-resistant resin into a fully functional self-healing polymeric composite.