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Globally, mental health conditions pose a substantial burden of disease. Despite the availability of evidence-based pharmacological and psychological treatments, the symptoms of a substantial subgroup of patients do not respond to these interventions, and only a minority of patients have access to them. This study aimed to assess the efficacy of ImPuls, a 6-month transdiagnostic group exercise intervention, plus treatment-as-usual, compared with treatment-as-usual alone in outpatients with various mental disorders.

In this study, the frequency down-conversion of terahertz waves is analytically and experimentally demonstrated at the temporal boundaries within a GaAs waveguide. The temporal boundary is established by photoexciting the top surface of the waveguide, thereby instantaneously increasing its electrical conductivity. This photoexcited waveguide supports a transverse electromagnetic (TEM) mode with a frequency lower than those of the transverse magnetic (TM) modes present in the original waveguide. At the temporal boundary, the incident TM mode couples with the TEM mode, resulting in frequency down-conversion. Subtracting the propagation loss from the frequency-converted components indicates that the frequency conversion occurs with an efficiency consistent with the analytical predictions. The propagation loss is primarily due to ohmic loss, caused by the finite electrical conductivity of the photoexcited region. Given that the frequency of transverse electric modes is up-converted at the temporal boundary, our findings suggest that the direction of frequency conversion (upward or downward) can be controlled by manipulating the incident polarization. The polarization-dependent frequency conversion in waveguides holds significant potential for applications in devices designed for the interconversion of terahertz signals across various frequency channels. This capability is instrumental in the development of frequency-division-multiplexed terahertz wave communication systems, thereby enabling high data transfer rates.

•A spinal arteriovenous fistula (AVF) can lead to cardiac arrest, but survival from out-of-hospital cardiac arrest (OHCA) has never been reported.•An 84-year-old female developed out-of-hospital cardiac arrest due to rapture of AVF.•Magnetic resonance imaging showed arterio-venous malformation at C2/3 level and angiography identified a spinal AVF.•Transarterial embolization of the AVF was performed on day 37. The patient recovered to Glasgow coma scale of 10 (E3VTM6), but no limb movements.•Future study will aid better management and outcome for this rare form of out-of-hospital cardiac arrest.

A reciprocal relationship between repetitive negative thinking (RNT) and negative affect (NA) has been found in various types of psychopathology. Recent studies have suggested that the magnitude of this association can vary across time and individuals, which may inform future psychopathology. Here, we explored how these dynamics and interplays are manifested in student and general populations using a statistical clustering algorithm. Across three experience-sampling data sets, our clustering analyses consistently identified two groups of individuals; one group had a higher bidirectional association between RNT and NA (and also higher inertia) than the other group. Furthermore, a prospective analysis revealed that the group with the higher bidirectional association is at risk of developing depressive symptoms during the 3-month follow-up period if they had experienced high levels of NA over the experience-sampling phase. These findings suggest that the dysfunctional affective and cognitive dynamics would be a promising target of preventive intervention.

Substantial enhancement of terahertz magnetic near field achieved by the combination of a tapered metallic waveguide and a micro-split-ring resonator is demonstrated. The magnetic near field is probed directly via the magneto-optic sampling with a Tb_3Ga_5O_12 crystal. The incident terahertz wave with a half-cycle waveform is generated by using the pulse-front tilting method. The magnetic near field at the resonant frequency is enhanced by more than 30 times through the combination of the waveguide and the resonator. The peak amplitude of the magnetic field with a damped oscillation waveform in the time domain is up to 0.4 T. The resonant frequency can be tuned by adopting different resonator designs. The mechanism of the enhancement is analyzed by performing calculations based on the finite element method. The strong terahertz magnetic near field enables the excitation of large-amplitude spin dynamics and can be utilized for an ultrafast spin control.

Several decades of research have established reduced autobiographical memory specificity, or overgeneral memory, as an important cognitive factor associated with the risk for and maintenance of a range of psychiatric diagnoses. In measuring this construct, experimenters code autobiographical memories for the presence or absence of a single temporal detail that indicates that the remembered event took place on a single, specific, day (Last Thursdaywhen I rode bikes with my son), or multiple days (When I rode bikes with my son). Studies indicate that the specificity of memories and the amount of other episodic detail that they include (e.g., who, what, and where) are related and may rely on the same neural processes to elicit their retrieval. However, specificityand detailednessare nonetheless separable constructs: imperfectly correlated and differentially associated with current and future depressive symptoms and other associated intrapersonal (e.g., rumination) and interpersonal (e.g., social support) outcomes. The ways in which the details of our memories align with narrative themes (i.e., agency, communion, identity) and the coherence with which these details are presented, are also emerging as important factors associated with psychopathology. The temporal specificity of autobiographical memories may be important, but other memory constructs warrant further attention in research and theory, especially given the associations, and dependencies, between each of these constructs. Researchers in this area must consider carefully whether their research questions necessitate a focus on autobiographical memory specificity or whether a more inclusive analysis of other autobiographical memory features is necessary and more fruitful. This article is categorized under:Psychology > Memory Our autobiographical memories are characterized by episodic (who, what, where and when [i.e., temporal specificity]) and semantic (general knowledge, metacognitive statements) details that can cohere into a narrative structure while representing motivational, affective and meaning‐making themes.

ABSTRACTBackground:Network analysis has gained increasing attention as a new framework to study complex associations between symptoms of post-traumatic stress disorder (PTSD). A number of studies have been published to investigate symptom networks on different sets of symptoms in different populations, and the findings have been inconsistent.Objective:We aimed to extend previous research by testing whether differences in PTSD symptom networks can be found in survivors of type I (single event; sudden and unexpected, high levels of acute threat) vs. type II (repeated and/or protracted; anticipated) trauma (with regard to their index trauma).Method:Participants were trauma-exposed individuals with elevated levels of PTSD symptomatology, most of whom (94%) were undergoing assessment in preparation for PTSD treatment in several treatment centres in Germany and Switzerland (n = 286 with type I and n = 187 with type II trauma). We estimated Bayesian Gaussian graphical models for each trauma group and explored group differences in the symptom network.Results:First, for both trauma types, our analyses identified the edges that were repeatedly reported in previous network studies. Second, there was decisive evidence that the two networks were generated from different multivariate normal distributions, i.e. the networks differed on a global level. Third, explorative edge-wise comparisons showed moderate or strong evidence for specific 12 edges. Edges which emerged as especially important in distinguishing the networks were between intrusions and flashbacks, highlighting the stronger positive association in the group of type II trauma survivors compared to type I survivors. Flashbacks showed a similar pattern of results in the associations with detachment and sleep problems (type II > type I).Conclusion:Our findings suggest that trauma type contributes to the heterogeneity in the symptom network. Future research on PTSD symptom networks should include this variable in the analyses to reduce heterogeneity.

We proposed and demonstrated terahertz (THz) pulse detection by means of multilayered GeTe/Sb2Te3phase-change memory materials that are also known as a multilayer topological insulator–normal insulator (MTN) system. THz time-domain spectroscopy measurement was performed for MTN films with different multilayer repetitions as well as a conventional as-grown Ge–Te–Sb (GST) alloy film. It was found that MTNs absorb THz waves and that the absorption coefficient depends on the number of layers, while the as-grown GST alloy film was almost transparent for THz waves. Simple MTN-based THz detection devices were fabricated, and the THz-induced change in the current signal was measured when a DC bias voltage was applied between the electrodes. We confirmed that irradiation of THz pulse causes a decrease in the resistance of the MTNs. This result indicates that our devices are capable of THz detection.

We demonstrate terahertz pulse generation from silver nanoparticle ink, originally developed for printed electronics, under irradiation by femtosecond laser pulses. Using metal nanoparticle ink, metallic nanostructures can be easily made in a large area without lithographic techniques. Terahertz pulses were emitted from the baked ink, having spontaneously formed nanostructures of ∼100  nm. From the results of the baking temperature dependence and the polarization measurement, the terahertz generation is attributed to the nonlinear polarization induced by the enhanced local fields around these nanostructures. This study paves the way for the future development of terahertz emitters which have resonances in both the near-infrared light and the terahertz wave, by combining micrometer-scale structures drawn by an inkjet printer and nanometer-scale structures formed during the baking process.

We demonstrate a sensor card with cholesteric liquid crystals (CLCs) for terahertz (THz) waves generated from a nonlinear crystal pumped by a table-top laser. A beam profile of the THz waves is successfully visualized as color change by the sensor card without additional electronic devices, power supplies, and connecting cables. Above the power density of 4.3  mW/cm^2, the approximate beam diameter of the THz waves is measured using the hue image that is digitalized from the picture of the sensor card. The sensor card is low in cost, portable, and suitable for various situations such as THz imaging and alignment of THz systems.

Quasi-monodisperse dielectric particles organized in a periodic hexagonal network on an aluminum surface are exploited numerically and experimentally as a single-layered near-perfect absorber in the terahertz regime. Of particular interest are titanium dioxide (TiO_2) microspheres because of their large dielectric permittivity and isotropic shape leading to Mie resonances with insensitive polarization. Absorption higher than 80% at normal incidence covering two distinct ranges of frequencies is demonstrated experimentally. Furthermore, the performance of the metamaterial absorber is kept over a wide range of incident angles.

Terahertz (THz) transmission modulation through copper phthalocyanine (CuPc)-coated Si under various laser light irradiation conditions was investigated using THz time-domain spectroscopy. The charge carrier transfer from Si to CuPc is crucial for photo-induced metallization, and the thickness of the CuPc layer is a critical parameter for achieving high charge carrier density for metallization. Transmission through a split-ring resonator array metamaterial, fabricated on CuPc-coated Si, can be efficiently modulated by laser light irradiation. Our findings may open the way for various types of metamaterials using organic conjugated materials that are suitable for easy device fabrication using printing technologies.

A two-dimensional dielectric metamaterial composed of a $\hbox{TiO}_{2}$ cube array is fabricated, and its performance is characterized in the terahertz region. The effective electromagnetic parameters are retrieved from the complex transmission and reflection coefficients of the sample, obtained using terahertz time-domain spectroscopy. The retrieved parameters show negative permeability and permittivity at around 0.28 and 0.38 THz, respectively. We also show via simulations that negative refractive index metamaterials can be realized by combining two sets of $\hbox{TiO}_{2}$ cubes of appropriate sizes. We also propose and fabricate composite structures made of $\hbox{TiO}_{2}$ spheres and a metal mesh to obtain a negative refractive index. The observed transmission band is attributed to the negative refractive index. $\hbox{TiO}_{2}$ is a promising material for fabricating negative refractive index metamaterials for the terahertz frequency region.

By using coupled-mode analysis, we investigate numerically the extraordinary optical transmission (EOT) of incommensurate metal hole arrays (IMHAs) in the terahertz region to study how the degree of long-range and short-range orders affect EOT. In IMHAs, the holes of one set of metal hole arrays (MHAs) are regarded to work as impurities to the holes of another set of MHAs. Therefore, the transmittance spectra are expected to be significantly modified from those of the constituent MHAs. It is found that the resonance transmission frequencies of IMHAs almost coincide with those of the composite MHAs despite the fact that the surface waves of each MHA are mutually perturbed strongly due to the presence of short-range disorder. This indicates that the presence of long-range order is essential to establish EOT. These observations allow more flexible design of narrow bandpass filters in the terahertz region.

•In cases of severe consciousness disorder with head injury, it is difficult to diagnose consciousness disorder due to VAI from cervical spine trauma because of insufficient physical and neurological findings.•We reported the case of a patient with extensive brain infarctions because of bilateral VAI without any remarkable CT findings suggestive of VAI.•When cervical hyperextension injury is suspected, CTA should be performed as early as possible to initiate early treatment of extensive brain infarction due to bilateral VAI.

Memory Specificity Training (MeST) is an intervention developed from basic science that has found clinical utility. MeST uses cued recall exercises to target the difficulty that some people with emotional disorders have in recalling personally experienced events. MeST is simple enough to be delivered alongside traditional interventions or online by artificial intelligence. Currently, research indicates MeST’s effects are immediate, but short lived, and there is limited research indicating its superiority over established interventions. Future investigations must establish the dosage and specific components of MeST that are necessary for clinically significant effects. Further, it must establish the secondary processes (e.g., problem-solving) that mediate between MeST-driven improvements in memory and symptoms. Similar interventions that build upon the idea of training autobiographical memory specificity are also emerging, and warrant further investigation.

We present the case of a 79-year-old woman who presented at our center with a periprosthetic tibial fracture with a popliteal artery injury after total knee arthroplasty. Anastomosis of the popliteal artery was performed on the day of injury, and was later treated by open reduction and internal fixation. The patient was able to walk 3 months after injury.

Wire-grid polarizer sheets in the terahertz region have been fabricated on flexible substrates by nanoimprint technology. They show an ideal polarization property in the terahertz frequency region, whereas the cost is very low. Since the wire pitch is far smaller than the wavelength, the effective medium theory agrees well with experimental results. The effective medium theory shows the possibility of further improvement of polarization properties by selecting appropriate materials for wire grids.

The absorption spectra of ceftazidime and its generic versions (Modacin, Mosyl, and Mobenzocin) have been measured by terahertz time domain spectroscopy (THz-TDS). Differences in the THz absorption were observed between the original and generic versions. The results show small, but significant differences in the states of ceftazidime hydrate between the original and generic versions. THz-TDS can be used to evaluate the stability of medicines as well as to control their quality.

We fabricated a terahertz wire-grid polarizer consisting of a micrometer-pitch Al grating on a Si substrate by photolithography and wet etching. The ratio of TM and TE transmittances (extinction ratio) was over 35 dB at 0.5 THz. At the Brewster angle of the Si substrate, the polarization transmittance of a TM wave through the fabricated polarizer exceeded 95% and the extinction ratio was over 45 dB at ~1 THz. The fabricated polarizer has a higher extinction ratio than conventional free-standing terahertz wire-grid polarizers.

Metallic sub-wavelength slit-array slabs act just like dielectrics when the incident wavelength is longer than the slit interval. However, their stacked structures do not always exhibit optical properties equivalent to conventional dielectric multilayers, which should be due to the lateral periodicity. This work investigated in detail the lateral displacement dependence on the characteristics of the Fabry-Perot-like waveguide resonance modes of two-tier systems. Simulation studies clarified the behavior of the resonance modes and the physical mechanism underpinning the transmission disappearance by the lateral displacement. Furthermore, we determined that the critical frequency, above which the even-order modes exhibit blue-shifts with increases in the air gap spacing, can be predicted very accurately using a simple equation including the lateral displacement. Additionally, the transmission characteristics assessed experimentally were compared with the simulation results. The geometrically-tunable unique optical characteristics are expected to promote the future applications of artificial dielectrics operating in low-frequency optical regions.

We investigated the optical transmission properties of quasi-dielectric metamaterials composed of a stack of metallic sub-wavelength slit-array slabs. First, we used simulations to predict the transmission properties, and showed that these characteristics are basically equivalent to those of triple-layered dielectrics below the diffraction-limit frequency. Next, for the experimental demonstrations, we fabricated the metallic slit arrays, and then measured the transmission spectra. By comparison of the theoretical and experimental results, we demonstrated that each slit array acts as an individual quasi-dielectric in the stacked system. Using these metamaterials, a variety of transmission characteristics can be obtained in the terahertz region.

We investigated the behavior of waveguide resonance modes in a metamaterial consisting of metallic slit-array slabs separated by an air gap. Simulation results show two unusual types of intersection phenomena. One type is an anticrossing with a specifically recognizable mode repulsion. An effective medium theory analysis revealed that this phenomenon can be explained in terms of an increased effective refractive index in the air-gap region. The other type of intersection leads to transmission suppression by the mixing of symmetric and asymmetric modes. This fade-out phenomenon is associated with a change in the behavior of the symmetric mode above a critical frequency.

Terahertz (THz)-transmission modulation through the Si substrate coated with four p-conjugated materials under various laser light irradiation conditions was investigated using THz time-domain spectroscopy. Two of the p-conjugated low molecules, the [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene), and two of the p-conjugated polymer materials, poly[5-(2-ethylhexyloxy)-2-methoxycyanoterephthalyliden] (MEH-CN-PPV) and poly(benzimidazobenzophenanthroline) (BBL), were investigated. Among these materials, PCBM and TIPS-pentacene showed higher modulation efficiencies and it was also shown that thermal annealing is quite effective in obtaining THz modulation efficiencies higher than those previously reported for copper phthalocyanine. Utilizing these solution-processable p-conjugated materials, various types of THz materials and devices could be fabricated by printing technologies. Our findings may open the way to fabricating various types of THz active devices.

A terahertz polarizer consisting of a laminated metal-slit array on a polymer film is presented. Here, the iterative design is efficiently performed with a mode-matching method; the proposed polarizer's characteristics are shown to be superior to those of conventional polarizers. To verify the proposed design, a copper metal-slit array was fabricated on a cyclo-olefin polymer film by sputtering and punching. Measurements confirm a high extinction ratio, below ?50 dB from 0.28 to 1.09 THz and below ?40 dB from 0.2 to 1.98 THz, with a TM-mode transmission power that averages 76% from 0.2 to 1.95 THz.

We show that a spectroscopic function can be achieved by an artificial combination of very thin metallic plates with modulated cut-through slit arrays by simulation using the finite-difference time-domain method. The novel function is based on the remarkable frequency dependences of optical phased array effects, i.e., the phase variations of optical waves threading through the slit arrays in multi-stacked metallic plates. We also present methods to enhance the phase shift.

We investigated the optical propagation properties of systems composed of two different metallic plates with cut-through slit arrays at artificially modulated intervals. Simulation studies using the finite-difference time-domain method showed that the phases of the light waves emitted from the slits can be changed by controlling the paths of the spoof surface plasmon polaritons (SPPs) in the air gap region sandwiched between the two arrays. Furthermore, by making use of the present optical phased array functions based on SPP-assisted optical transmission phenomena, the lens like effects of both convex and concave are demonstrated.

Super-fine ink-jet (SIJ) printing technology is applied to the fabrication of terahertz metamaterials. A silver film is fabricated using an SIJ printer with silver paste ink, and it is confirmed that the film behaves as a good conductor in the terahertz frequency region. Then, basic terahertz metamaterials such as metal wire-grid structures and split-ring resonators are printed on high-resistivity silicon substrates. The terahertz responses of the printed samples agree with those expected from their structures. SIJ printing is one of the ideal methods for fabricating terahertz metamaterials owing to its rapidity, simplicity, flexibility, and sufficient accuracy.