Harnessing the full complexity of optical fields requires the complete control of all degrees of freedom within a region of space and time—an open goal for present-day spatial light modulators, ...active metasurfaces and optical phased arrays. Here, we resolve this challenge with a programmable photonic crystal cavity array enabled by four key advances: (1) near-unity vertical coupling to high-finesse microcavities through inverse design; (2) scalable fabrication by optimized 300 mm full-wafer processing; (3) picometre-precision resonance alignment using automated, closed-loop ‘holographic trimming’; and (4) out-of-plane cavity control via a high-speed μLED array. Combining each, we demonstrate the near-complete spatiotemporal control of a 64 resonator, two-dimensional spatial light modulator with nanosecond- and femtojoule-order switching. Simultaneously operating wavelength-scale modes near the space–bandwidth and time–bandwidth limits, this work opens a new regime of programmability at the fundamental limits of multimode optical control.Panuski et al. demonstrate a programmable photonic crystal cavity array, enabling the spatiotemporal control of a 64 resonator, two-dimensional spatial light modulator with nanosecond- and femtojoule-order switching.
Abstract Why has North Korea avoided capitulating to economic sanctions pressures? We argue that economic sanctions have been ineffective and unsuccessful for three reasons: North Korea’s adeptness ...at evasion, other states’ unwillingness to enforce economic sanctions, and North Korea’s efforts to avoid panopticon effects via its diplomatic statecraft and policies that allow states to monitor and collect information on others. We contend that the implementation and enforcement of economic sanctions led North Korea to alter its trading network, reallocating trade to countries (or nodes) within its network willing to ignore international sanctions. As a result, these network shifts limited the ability of senders to weaponize the interdependence between them and North Korea effectively. We further highlight how North Korea conducts diplomatic statecraft in such a way that limits the impact of sanctions enforcing states from effectively monitoring it and limiting the impact of panopticon effects senders generate. To test our theory, we employ an ordinary least squares regression followed by social network analysis to understand how North Korea’s network of trade has adapted over time in the face of punishing economic sanctions. We find that states with greater diplomatic engagement enjoy better centrality than sanctions enforcing states. Also, economic sanctions at critical junctures induce changes to North Korea’s network over time with commercial imperatives to trade replaced by a North Korean near reliance on China. We further demonstrate that economic sanctions likely induce changes to the structure of the network as North Korea seeks to insulate itself from the impact of economic sanctions.
Examining Recidivism in a Prostitution Diversion Program Koegler, Erica; Preble, Kathleen M.; Cimino, Andrea N. ...
International journal of offender therapy and comparative criminology,
02/2020, Letnik:
64, Številka:
2-3
Journal Article
Recenzirano
Street-based sex work is criminalized throughout much of the U.S. Diversion programs have shown mixed results. This study examined the effect a quasi-experimental intervention (prostitution diversion ...program, n = 149) had on prostitution rearrest compared with a waitlist control group (n = 77) among N = 226 individuals arrested for prostitution in Baltimore. In both groups, n = 64 (28.32%) were rearrested for prostitution over 30 months. Tests of differences compared groups with a significant difference in gender only. A Cox proportional hazard model examined differences in survival time (to recidivist prostitution arrest) between individuals in the control and intervention groups at 6, 12, 18, 24, and 30 months. Results indicate that participation in the intervention did not have a significant effect on decreasing prostitution arrests over time. History of prior prostitution arrest was a significant predictor (hazard ration HR = 1.12, p = .02) of rearrest.Lack of program success suggests that barriers to exiting prostitution are substantial, despite availability of supportive services, and that diversion programs may not be the best intervention strategy for all sex workers. Future research should identify motivators for exiting and how to reduce exiting barriers.
Systematic site-specific comparisons of the densities of threading dislocations (TDs) and associated V-defects in six-period InxGa1−xN/GaN multi-quantum wells (MQWs) with In mole fractions of x=0.1 ...and 0.2 have been conducted using several electron microscopy techniques including electron channeling contrast imaging. The MQWs were grown on GaN epitaxial films deposited on either (0001) GaN substrates or on (0001)AlN/6H-SiC heterostructures. The densities of TDs and V-defects in the surfaces of the homoepitaxial GaN films and the In0.1Ga0.9N/GaN MQWs were both 5.5×106cm−2. By contrast, the V-defect densities in the In0.2Ga0.8N/GaN MQWs exceeded by two and three times the densities of TDs measured in the surfaces of the underlying GaN films grown on GaN and AlN/SiC substrates, respectively. Similar observations of V-defects not associated with threading dislocations have been previously reported to occur in InGaN MQWs grown on GaN template films on sapphire substrates and having either an initially high In mole fraction or grown at the end of a series of MQWs with an increasing In mole fraction. From a synthesis of the results of this previous work using GaN/sapphire substrates with the present results for bulk GaN substrates, it is hypothesized that increases in stress generated by the larger mismatches in lattice parameters between the GaN film and the In0.2Ga0.8N/GaN MQWs and the additional stresses generated between the GaN barriers and the wells within these MQWs generated new TDs within the MQWs, which then acted as nucleation centers for new V-defects.
•Electron channeling contrast imaging (ECCI) and transmission electron microscopy (TEM) were used for site-specific studies of InGaN/GaN multi-quantum wells.•Densities of threading dislocations and V-defects were compared at key stages of the growth process on SiC and GaN substrates.•A one-to-one correspondence between V-defects and threading dislocations was found in In0.1Ga0.9N/GaN multi-quantum wells.•The V-defect density exceeded the threading dislocation density in higher In-concentration In0.2Ga0.8N/GaN multi-quantum wells.
Teen Dating Violence (TDV) is a public health issue that has long lasting implications into adulthood. Making matters more precarious is the scant evidenced-based information available to parents to ...help them respond to teens' reports of TDV exposure. This study examined parental and youth perceptions of the helpfulness and likelihood of use of suggested parental responses to dating violence. Results indicated that parents' potential supportive comments about “rights” and “whose fault” were viewed as the most helpful and likely to be used. The least approved statements were connected to parents' threatening punishment. The most endorsed comments provide information without undermining the teens' self-esteem and offer insight about how parents can promote more helpful dialogs about teens' experiences with dating violence.
•Parents and youth did not differ in their perceptions of helpful parental responses to ADV.•Parental responses to ADV focused on rights of the victim and fault of the perpetrator were perceived as helpful.•Most endorsed parental response to ADV provided support without undermining youths’ self-esteem.•Male and female teens did not differ in perceptions of parental ADV response helpfulness.•Teens with ADV experiences perceived statements distinguishing guilt and responsibility as helpful.
To determine the feasibility of short-term cardiovascular responses to postural change as a screening tool for mild traumatic brain injury (mTBI), using heart rate metrics that can be measured with a ...wearable electrocardiogram sensor.
Military TBI clinic.
Data collected from active-duty service members who had sustained a medically diagnosed mTBI within the prior 72 hours and from age- and sex-matched controls. Cardiac data collected while participants performed a sequence of postural changes.
Model classification compared with clinical mTBI diagnosis.
Cardiac biomarkers of mTBI were identified and logistic regression classifiers for mTBI were developed from different subsets of biomarkers. The best model achieved 90% sensitivity and 69% specificity using data from 2 different postural changes.
Noninvasive measurement of cardiovascular response to postural change is a promising approach for field-deployable post-mTBI screening.
This study examines the relationships between exposure to violence in the community, school, and family with dating violence attitudes and behaviors among 175 urban African American youth. Age, ...gender, state support and experiences with neglect, school violence, and community violence were the most significant predictors of acceptance of dating violence. Experiences with community violence and age were important predictors of dating violence perpetration and victimization. Findings highlight the importance of planning prevention programs that address variables affecting attitudes and behaviors of high-risk youth who have already been exposed to multiple types of violence.
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