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Obstructive sleep apnea (OSA) has been associated with cognitive deficits as evidenced by neuropsychological testing in the domains of attention/working memory, verbal memory, processing speed, and executive function. OSA is often comorbid with hypertension and has been considered a risk factor for hypertension (Kareem et al., 2018; Tietjens et al., 2019). Both hypertension and OSA have been shown to be independent predictors of memory (Kinoshita et al., 2012). OSA and posttraumatic stress disorder (PTSD) are also frequently co-occurring, especially among veterans. In a group of veterans with a history of PTSD, we seek to explore the effects of sleep apnea and hypertension on cognitive functioning, particularly auditory learning/memory.
Participants and Methods:
One hundred and three male and female participants with comorbid OSA and PTSD symptomology were screened as part of a larger VA Palo Alto Health Care System study. Participants (age: x=56.3, a=13.8, 24-81 years; education: x=14.6, a=2.3, 8-20 years; 9.6% female, 89.6% male) completed a neuropsychological battery, including the CVLT-II and WMS-IV Logical Memory. Presence or absence of hypertension was dichotomously coded and AHI severity was categorically coded. An auditory learning/memory composite variable was created using the z-score transformation method (Dodge et al., 2020). Variables and covariates were entered into a hierarchical regression.
Results:
The initial regression model revealed hypertension and OSA severity to be independent predictors of performance on auditory learning/memory (hypertension: ß= -0.71, p<0.01; OSA: ß= -0.42, p<0.01), where presence of hypertension or increased severity of OSA resulted in worse performance on the auditory learning/memory composite.
Conclusions:
Results suggest that hypertension and OSA may independently and negatively affect performance on measures of auditory learning/memory in veterans with PTSD symptomology and OSA. Such findings underscore the importance of assessing and treating both hypertension and OSA among veterans with PTSD to improve not only physical health, but also cognitive health. Further research demonstrating similar findings is recommended along with studies investigating whether or not the treatment of hypertension and OSA can improve auditory learning/memory.
Both Apolipoprotein z4 (APOz4) and Brain-Derived Neurotropic Factor val66met (BDNF-met) have been implicated as cognitive risk polymorphisms and may signal a more rapid trajectory of cognitive decline (Boots et al., 2017; Lim et al., 2015). The presence of both risk alleles may additively result in greater cognitive difficulties (Cechova et al., 2020), specifically executive functioning (Sapkota et al., 2017). As executive functioning difficulties can be associated with Posttraumatic Stress Disorder (PTSD; Woon et al., 2017), individuals with PTSD who carry these polymorphisms may be at higher risk for decline in executive functioning. In this study, we examined the cross-sectional and longitudinal impact of these alleles on executive functioning performance in Veterans with PTSD.
Participants and Methods:
Seventy community-dwelling male Veterans were enrolled as part of a larger study at VAPAHCS and consented to genetic analysis. A current or lifetime history of PTSD (score > 40 on the CAPS-IV; Blake et al., 1995) was required for study participation. Trail Making Test B (TMT-B; Army Individual Test Battery, 1994) was used to assess executive functioning. TMT-B was part of a comprehensive neuropsychological battery administered at baseline and yearly over the following three years. Mean age and education were 61 years old (SD = 4.5; range = 55-78) and 14 years (SD = 2.3; range = 8-20), respectively.
The majority of the sample was White (71%) and were from the Korean and Vietnam War eras.
Results:
APOz4 and BDNF-met were present in 29% and 27% of the sample, respectively; both were present in six participants. Regression models were fitted separately for TMT-B raw time-to-complete and number of errors, both cross-sectionally at screening and then longitudinally. The presence of BDNF-met was a significant predictor of TMT-B time and number of errors in both models (Time: ß = 0.09, p = 0.03 and ß = 0.11, p < 0.01; Errors: IRR = 2.4, p = 0.01 and IRR = 1.9, p = 0.01), while APOz4 only predicted errors longitudinally (IRR = 1.8, p = 0.03). There was no significant allelic interaction; however, the presence of both alleles additively multiplied TMT-B errors by approximately 3.7 times at screening (IRR = 3.7; p = 0.01) and 3.3 times longitudinally (IRR = 3.3; p < 0.01).
Conclusions:
Altogether, these results are suggestive of an adverse, additive, effect of the APOz4 and BDNF-met polymorphisms on executive functioning, in particular error-proneness, with their combined presence tripling the errors made on TMT-B cross-sectionally and longitudinally. Consistent with previous research, the TMT-B error analysis increases detection of cognitive impairment, similar to other clinical samples (Varjacic et al., 2018). While TMT-B errors are typically interpreted qualitatively, the strong effect of these established risk alleles on error rates further support this metric as a clinically useful indicator of executive dysfunction in a PTSD population. In keeping with the Boston Process approach, these findings support the importance of error analysis in clinical interpretation of neuropsychological performance.
During the COVID-19 pandemic, the use of telemedicine as a way to reduce COVID-19 infections was noted and consequently deregulated. However, the degree of telemedicine regulation varies from country to country, which may alter the widespread use of telemedicine. This study aimed to clarify the telepsychiatry regulations for each collaborating country/region before and during the COVID-19 pandemic.
Methods
We used snowball sampling within a global network of international telepsychiatry experts. Thirty collaborators from 17 different countries/regions responded to a questionnaire on barriers to the use and implementation of telepsychiatric care, including policy factors such as regulations and reimbursement at the end of 2019 and as of May 2020.
Results
Thirteen of 17 regions reported a relaxation of regulations due to the pandemic; consequently, all regions surveyed stated that telepsychiatry was now possible within their public healthcare systems. In some regions, restrictions on prescription medications allowed via telepsychiatry were eased, but in 11 of the 17 regions, there were still restrictions on prescribing medications via telepsychiatry. Lower insurance reimbursement amounts for telepsychiatry consultations v. in-person consultations were reevaluated in four regions, and consequently, in 15 regions telepsychiatry services were reimbursed at the same rate (or higher) than in-person consultations during the COVID-19 pandemic.
Conclusions
Our results confirm that, due to COVID-19, the majority of countries surveyed are altering telemedicine regulations that had previously restricted the spread of telemedicine. These findings provide information that could guide future policy and regulatory decisions, which facilitate greater scale and spread of telepsychiatry globally.
We analysed associations between exposure to nightlife businesses and severe acute respiratory syndrome coronavirus 2 PCR test results at a tertiary hospital in Tokyo between March and April 2020. A nightlife group was defined as those who had worked at or visited the businesses. We included 1517 individuals; 196 (12.9%) were categorised as the nightlife group. After propensity score matching, the proportion of positive PCR tests in the nightlife group was significantly higher than that in the non-nightlife group (nightlife, 63.8%; non-nightlife, 23.0%; P < 0.001). An inclusive approach to mitigate risks related to the businesses needs to be identified.
A magnetic field configuration of an island divertor for a quasi-axisymmetric stellarator (CFQS) is proposed. The configuration incorporates large islands surrounding the core confinement region. The interface between the core region and the peripheral region of the island divertor is a clear magnetic separatrix similar to a tokamak divertor. The structure of divertor magnetic field lines is very regular without stochasticity and the connection length is sufficiently long for good divertor performance. Such a divertor configuration is produced in the magnetic field configuration for the CFQS device, which is now under construction in China.
The corpus callosum (CC) is the largest interhemispheric white matter commissure connecting the cerebral hemispheres and plays a crucial role in interhemispheric communication and cognitive processes. The subdivisions of the CC were attempted to define corresponding areas of the cortex from which the fibers originate. Previous neuroanatomic studies of the CC provide impetus for investigating its role in obsessive-compulsive disorder (OCD).
Methods:
In this study diffusion tensor imaging (DTI) was employed to microstructural abnormalities of white matter of the CC in OCD patients. Nine patients with OCD and matched control subjects underwent DTI. Fractional anisotropy (FA), an index of the integrity of white matter tracts, was determined in the seven subdivisions of the CC.
Results:
Significant reduction in FA was found in the rostrum of the CC of patients with OCD compared with one of controls. FA of the other subdivisions except the rostrum in OCD patients did not differ compared with control subjects. Higher FA in the rostrum correlated with lower Y-BOCS scores (r = -0.852, p = 0.004).
Conclusions:
The rostrum contains fibers from inferior premotor as well as medial and caudate/orbital prefrontal regions. These results supported the theory of dysfunction of prefrontal cortex and striatal circuits in OCD and suggested the implication of the orbitofrontal circuit for symptom severity in the OCD patients.
Variability in antidepressant response is due to genetic and environmental factors. Among genetic factors, the ones controlling for availability of the drug at the target site are interesting candidates. Rs6295C/G SNP for 5-HT1A gene (HTR1A) has been found to effect the expression and function of HTR1A In fact rs6295C/G was in strong linkage disequilibrium with other polymorphisms of HTR1A suggesting that those functional effects could be associated with polymorphisms other than the synonymous rs6295C/G. In the present study we examine the possible association of a panel of markers in strong linkage disequilibrium of the HTR1A with SSRI/SNRI response in 137 Japanese major depression sample followed for 6 weeks. We observed the significant association of better response to antidepressant with rs10042486C/C (p<0.0001), rs6295G/G (p<0.0001) and rs1364043T/T (p=0.018) genotype carriers, that is mutant allele homozygote, independently from clinical variables. Furthermore mutant allele homozygote carriers in all these 3 SNPs was associated more solidly with treatment response by various assessment such as HAM-D score change over time (p=0.001), week 2 (p<0.0001), 4(p=0.007), and 6(p=0.048) as well as response rate (p=0.0005) and remission rate (p=0.004).
In conclusion, this is the first study that reports the significant association of antidepressant response with rs10042486C/T and rs1364043G/T variants of HTR1A and also with rs10042486-rs6295-rs1364043 combination. This finding adds an important piece of information for the pathway of detecting the genetics of antidepressant response even if results must be verified on larger samples.
Altered levels of phenylalanine and its metabolites in blood and cerebrospinal fluid have previously been reported in schizophrenia. This study attempted to examine whether phenylalanine kinetics is altered in schizophrenia using the 13C-phenylalanine breath test (13C-PBT).
Methods
Subjects were 20 patients with schizophrenia and the same number of controls. 13C-phenylalanine was administered and then 13CO2 concentration in breath was monitored for 120 minutes. The Δ 13CO2 at each collecting time, the maximal Δ 13CO2 (Cmax), the time to reach Cmax (Tmax), the area under the curve of time course of Δ13CO2 (AUC), the cumulative recovery rate (CRR) at each collecting time of the 13C-PBT were calculated for each subject.
Results
Body weight (BW) and diagnostic status were significant predictors for Cmax. BW, age and diagnostic status were significant predictors for AUC and CRR at 120 minutes (CRR0-120). A repeated measures ANCOVA controlling for age and BW revealed a different pattern of change in CRR over time between the patients and controls and that Δ13CO2 in schizophrenia were lower than that in healthy control at all sampling point during 120 min, with an overall significant differences between healthy control and schizophrenia. The ANCOVA controlling for age and BW, showed that Cmax, AUC and CRR0-120 were significantly lower in schizophrenics than in controls.
Conclusions
Our data indicate the different change of Δ13CO2 and CRR over time and the decreased Cmax, AUC and CRR0-120 of 13C-PBT in schizophrenia patients compared to healthy controls, suggesting the altered phenylalanine kinetics in schizophrenia.
Smoking rates in schizotypic individuals are shown to be elevated, as in patients with schizophrenia, although findings on the association of smoking with different symptomatology of schizotypy have been mixed. Moreover, possible moderating effects of schizotypy on the relationship between smoking and cognition have not been well documented.
Subjects and methods
The Schizotypal Personality Questionnaire (SPQ) and the full version of the Wechsler Memory Scale-Revised (WMS-R) were administered to 501 healthy adults. Subjects were divided into smokers (n = 85) and non-smokers (n = 416) based on the presence/absence of current smoking.
Results
The analysis of covariance (ANCOVA) on the three factor scores as well as the total score of the SPQ, controlling for age and gender, revealed that cognitive-perceptual factor was significantly associated with an increased rate of smoking (P = 0.048). The ANCOVA on the WMS-R indices, with smoking group as a fixed factor and age, gender and total SPQ score as covariates, revealed that the schizotypy-by-smoking interaction was significant for attention/working memory (P = 0.029).
Discussion and conclusion
Positive schizotypy may be associated with more smoking. Schizotypy and smoking could interact with each other to negatively affect attention/working memory.
It has been reported that cognitive functioning in major depressive disorder (MDD) can be affected by various factors, such as symptom severity, personality dimensions and stress hormone activity. However, the relative role of each is largely unknown.
Methods
Seventy-six non-remitted patients with MDD were recruited. Symptomatology was assessed by the 21-item version of the Hamilton Rating Scale for Depression and the Hopkins Symptom Checklist (HSCL). Personality was assessed by the Temperament and Character Inventory (TCI). Neurocognitive functions, including verbal and visual memory, delayed recall and attention/working memory were measured by the full version of the Wechsler Memory Scale-Revised. Neuroendocrine function was determined by the reactivity of cortisol and dehydroepiandrosterone-sulfate (DHEAS) to the combined dexamethasone/corticotropin releasing hormone test. To quantify cognitive impairments in patients, age-, sex- and education- matched 187 healthy controls were also recruited and administered the same neuropsychological test.
Results
MDD patients performed significantly worse than controls on visual memory and delayed recall. A stepwise multiple regression analysis predicting performance of each cognitive domain from five HSCL dimensions, seven TCI dimensions and hormonal variables, controlling for age, gender and education, revealed that higher cooperativeness was the only significant predictor towards better verbal memory, that less somatization symptoms and lower self-directedness were significant predictors towards better visual memory, and that lower age, less anxiety symptoms and lower DHEAS levels after dexamethasone administration were significant predictors towards better delayed recall.
Conclusions
Besides symptomatology, some personality dimensions and neuroendocrine function may, at least partly independently, contribute to memory impairment in MDD.
The mode of onset and the course of schizophrenia illness exhibit substantial individual variations. Previous studies have pointed out that the mode of onset affects the duration of untreated psychosis (DUP) and clinical outcomes, such as cognitive and social functioning. This study attempted to clarify the association between the DUP and clinical features, taking the different modes of onset into consideration, in a prospective longitudinal study examining patients with first-episode schizophrenia.
Methods
This study was conducted in six areas of Japan. Patients with first-episode schizophrenia were followed for over 18 months. Cognitive function, psychopathology, and social functioning were assessed at baseline and at 6, 12, and 18-month follow-up points.
Results
We identified 168 patients and sufficient information was available to determine the DUP and the mode of onset for 156 patients (92.9%): 79 had an acute onset, and 77 had an insidious onset. The DUP was significantly associated with quality of life (QOL), social functioning, and cognitive function at most of the follow-up points in the insidious-onset group. The DUP and negative symptoms at baseline were significant predictors of cognitive function at the 18-month follow-up in the insidious-onset group.
Conclusions
The present results further support the hypothesis that the DUP affects QOL, social functioning, and cognitive function over the course of illness, especially in patients with an insidious onset. Effective strategies for detecting and caring for individuals with insidious onset early during the course of schizophrenia will be essential for achieving a full patient recovery.
Large variation in basic memory properties is a serious issue that hinders the practical use of ReRAM. This study revealed that one of the main factors causing variation is the presence of multiple filaments which have distinct set voltages in each memory cell. An operating filament switches to another filament having the smallest set voltage at each instant of switching. We propose a resistive switching model that takes the presence of multiple filaments into consideration. A Monte Carlo simulation based on the resistive switching model reproduces the set voltage distribution. Improvement of accuracy of the simulation can be also expected considering the fact that Vset increases at a certain probability at each instant of set switching.
We propose a parallel resistance model (PRM) in which total resistance (Rtotal) is given by the parallel connection of resistance of a filament (Rfila) and that of a film excluding the filament (Rexcl)—that is, 1/Rtotal = 1/Rfila + 1/Rexcl—to understand direct current (dc) electric properties of resistive random-access memory (ReRAM). To prove the validity of this model, the dependence of the resistance on temperature, R(T), and the relative standard deviation (RSD) of RHRS of Pt/NiO/Pt on the area of a top electrode, S, are investigated. It is clarified that both the R(T) and RSD depended on S, and all such dependencies can be explained by the PRM. The fact that Rtotal is decided by the magnitude relation between Rfila and Rexcl makes transport properties S-dependent and hinders the correct understanding of ReRAM. Smaller S is essential to observe the intrinsic transport properties of ReRAM filaments.
This study examined the prevalence of HIV and other sexually transmitted infections (STIs) in pregnant women in Kinshasa, the Democratic Republic of the Congo (DRC). Between April and July 2004, antenatal attendees at two of the largest maternity clinics in Kinshasa were tested to identify HIV status, syphilis, Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). HIV seroprevalence was 1·9% in 2082 women. With PCR techniques, CT and NG infections were also uncommon in the first 529 women (1·7% and 0·4%, respectively). No active syphilis infection case was identified by Treponema pallidum haemagglutination assay (TPHA) and rapid plasma reagin test (RPR). A woman's risk of HIV infection was significantly associated with her reporting a male partner having had other female sexual partners (OR 2·7, 95% CI 1·2–6·2). The continuing low seroprevalence of HIV in pregnant women from Kinshasa was confirmed. Understanding factors associated with this phenomenon could help prevent a future HIV epidemic in low HIV transmission areas in Africa.
Phase-change memory is promising because it has a simple structure and has scalability that originates from its unique operating mechanism. However, the programming current should be reduced in accordance with the scaling of cell size [1,2]. We previously reported PCM (Phase Change Memory) cells that operate under 1.5-V/100-μA writing pulses [3, 4]. This PCM had a cell structure composed of 180-nm-W (tungsten) bottom contact to an O-GST (Oxygen-doped GeSbTe) film. Its low-power characteristic is suitable for 0.13-μm generation embedded applications. In the present study, we introduced a new W/O-GST/TaO/W cell structure and found further decrease of programming current the improved stability in the fabrication process. We analyzed the mechanism by which oxygen in GST and the additional TaO layer reduce the power consumption during SET/RESET operations.
We systematically investigated the optimum growth condition of wide-bandgap quaternary InAlGaN for ultraviolet (UV) light-emitting diodes (LEDs) grown on SiC by metal organic vapor phase epitaxy (MOVPE). We obtained intense UV emission in the wavelength of 315-370 nm from quaternary InAlGaN, which was as high as blue emission from InGaN. We found that the optimized growth temperature of quaternary InAlGaN is shifted from 790 to 870 °C as the emission peak wavelength is changed from 370-315 nm. The strongest PL was obtained with the wavelength around 330 nm. The growth condition for intense PL is found to be decided by two factors, i.e., the carrier confinement in In segregation region and crystalline quality. We also found that the small In mole fraction of 2-5 % is enough to obtain maximally PL intensity for InAlGaN, which is much smaller value than that for InGaN, due to the large carrier confinement with small In fluctuation.
Optical and electrical properties of 340 nm-band bright UV-light emitting diodes (LEDs) were compared between In0.03Al0.20Ga0.77N and other active regions. Single peaked and high efficiency ultraviolet (UV) emission at 345 nm from In0.03Al0.20Ga0.77N LEDs is achieved under continuous current injection conditions. Any significant broadening and peak shift of the electroluminescence (EL) spectrum were not observed. We attribute such a good properties to using of high quality InAlGaN-quaternary active layer. The EL intensity of the InAlGaN quaternary-based LED showed more one order of magnitude higher intensity than that of AlGaN and GaN based LEDs. Additionally, The I-L characteristics of the InAlGaN quaternary-based LED showed a linearly increasing of intensity with increasing of injection current density, that is also observed for InGaN based LEDs. This shows the recombination efficiency of the InAlGaN-based LED is as much as that of InGaN based LEDs. From these results InAlGaN quaternary is expected to be a promising material for UV LEDs and LDs.
Optical and electrical properties of 340 nm-band bright UV-light emitting diodes (LEDs) were compared between In0.03Al0.20Ga0.77N and other active regions. Single peaked and high efficiency ultraviolet (UV) emission at 345 nm from In0.03Al0.20Ga0.77N LEDs is achieved under continuous current injection conditions. Any significant broadening and peak shift of the electroluminescence (EL) spectrum were not observed. We attribute such a good properties to using of high quality InAlGaN-quaternary active layer. The EL intensity of the InAlGaN quaternary-based LED showed more one order of magnitude higher intensity than that of AlGaN and GaN based LEDs. Additionally, The I-L characteristics of the InAlGaN quaternary-based LED showed a linearly increasing of intensity with increasing of injection current density, that is also observed for InGaN based LEDs. This shows the recombination efficiency of the InAlGaN-based LED is as much as that of InGaN based LEDs. From these results InAlGaN quaternary is expected to be a promising material for UV LEDs and LDs.
We have succeeded in the synthesis of strong Cu(111) textured films by means of the novel ion plating method(URT-IP). This URT-IP method combines the Cu deposition with the surface cleaning (self-cleaning). In the Cu film synthesis, the cations play a main role: the self-cleaning of underlying Cu seed and TaN barrier surfaces at the first stage of Cu deposition and the promotion of (111) texture. The two growth processes dependent on underlying materials cause the strong (111) orientation; the epitaxial growth on the same (111) oriented underlayer and the promotion of thermodynamically stable (111) texture on the amorphous underlayer. The in-situ Ar+ cleaning of underlayer surfaces by the URT-IP improves the (11) orientation to be much stronger. The URT-IP method is applied also to the synthesis of strong Pt(111) textured films with the same fcc system.