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1

Yao, Yong Zhao, Yukari Ishikawa, Yoshihiro Sugawara, Koji Sato, Katsunori Danno, Takayuki Shirai, Kazuaki Sato, et al. "Dislocations in SiC Revealed by NaOH Vapor Etching and a Comparison with X-Ray Topography Taken with Various g-Vectors." Materials Science Forum 858 (May 2016): 389–92. http://dx.doi.org/10.4028/www.scientific.net/msf.858.389.

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Threading dislocations (TDs) in 4H-SiC have been studied by comparing etch pits formed by NaOH vapor etching with results of synchrotron monochromatic-beam X-ray topography (XRT) taken under different g-vectors. Burgers vectors determined based on XRT results were utilized to investigate the etch pit characteristics of edge (TED), screw (TSD) and mixed (Burgers vector b=c+a, TMD) threading dislocations. It has been found that pit formation by NaOH vapor etching was very different to that by conventional molten KOH etching. We discuss the possibility of using NaOH vapor etching to distinguish TMDs from TSDs, and report a variety of characteristic etch pits formed by this method and their correlations to dislocation behavior.
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2

Cheon, J., F. Hong, T. Hidaka, H. Koshikawa, and H. Tsuno. "Microbial population dynamics in a thermophilic methane digester fed with garbage." Water Science and Technology 55, no. 10 (May 1, 2007): 175–82. http://dx.doi.org/10.2166/wst.2007.320.

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The diversity of microbial communities in three full-scale thermophilic anaerobic digesters which treated garbage, sewage sludge and livestock wastes (hereafter called TGD, TSD and TLD, respectively) was investigated using 16S rDNA clone libraries in triplicate. The population dynamics of TGD were also studied. The purposes were to show the microbial diversity in each reactor and to suggest which key microbes in a thermophilic methane digester fed with garbage, including a check of reproducibility and the suggestion of an error range in this molecular biology method. 736 clones were identified, and the maximum error was estimated to be around ±10% for the same OTU (operational taxonomic unit) and for most detected OTUs. The most frequently detected OTU shows a close relationship to Uncultured bacterium clone MBA08,Unidentified bacterium clone TUG22 and Uncultured archaeal symbiont PA204 in TGD, TSD and TLD, respectively. The microbial population dynamics in TGD were studied over a period of 90 days, and the occupying ratios of Bacillus infernus and Methanothermobacter wolfeii were shown to change with the change in VFA concentration. From the dynamic change and characteristics of the microbes, it is concluded that Bacillus infernus and Methanothermobacter wolfeii played an important role and were recommended as key microbes in TGD.
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3

Yao, Yong Zhao, Yukari Ishikawa, Yoshihiro Sugawara, Koji Sato, Katsunori Danno, Hiroshi Suzuki, Hidemitsu Sakamoto, Takeshi Bessho, Satoshi Yamaguchi, and Koichi Nishikawa. "Dislocation Revelation for 4H-SiC by Using Vaporized NaOH: A Possible Way to Distinguish Edge, Screw and Mixed Threading Dislocations by Etch Pit Method." Materials Science Forum 778-780 (February 2014): 346–49. http://dx.doi.org/10.4028/www.scientific.net/msf.778-780.346.

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In this paper, we report a newly developed dislocation-revealing etch pit method for 4H-SiC single crystal, which can distinguish edge (TED, Burgers vector b=a), elementary screw (TSD, b=1c) and mixed (TMD, b=c+a) threading dislocations. In this method, vaporized NaOH gas was used to etch the Si-face of a SiC wafer at substrate temperature around 950 °C. By a side-by-side comparison between the optical images of the etch pits and the X-ray topographic (XRT) images, it has been found that threading dislocations (TDs) in SiC could be revealed as hexagonal etch pits with distinct geometrical features (shape, size and facet orientation) depending on their Burgers vectors. Based on these results, we consider this etch pit method as an easily-operated and inexpensive technique to categorize TDs, and it may help to promote our understanding on the different roles that these types of TDs have played in the performance degradation of SiC power devices.
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4

Yamamoto, Kensaku, M. Nagaya, H. Watanabe, E. Okuno, T. Yamamoto, and S. Onda. "Influence of Threading Dislocations on Lifetime of Gate Thermal Oxide." Materials Science Forum 717-720 (May 2012): 477–80. http://dx.doi.org/10.4028/www.scientific.net/msf.717-720.477.

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The reliability of gate oxides is a fundamental issue for realizing SiC MOSFETs. Many reports said that crystal defects shorten the lifetime of the gate oxide. And, epi defects, the basal plane dislocations and threading screw dislocations (TSD) are considered killer defects. However, because of the high TSD density of commercial SiC wafers, the exact relationship between other kinds of dislocations with lifetime has not been revealed. On the other hand, RAF wafers that we developed have low TSD density, so it is easy to evaluate the relationship between other kinds of dislocations and lifetime. By using RAF wafers, in this study, we clarified the relationship between the lifetime of the gate oxide and crystal defects. We fabricated MOS diodes and measured their lifetimes by TDDB (Time Dependent Dielectric Breakdown) measurement. The breakdown points were defined by the photo-emission method. Finally, we classified the defects by TEM (Transmission Electron Microscopy). As the results, it was clarified that threading edge dislocation (TED) decreases the lifetime as does TSD, which earlier reports said. The lifetime of the gate oxide area, in which a TED is included, was shorter by one order of magnitude than a wear-out breakdown. And, the TSD was two orders.
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5

Kaur, Savreen. "Evaluation of Effectiveness of Three Different Behavioral Modification Techniques among 4–8-year-old Children." Current Trends in Dentistry 1, no. 1 (January 2024): 33–37. http://dx.doi.org/10.4103/ctd.ctd_7_24.

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Abstract Background: Dental anxiety being attributed by many as a major cause to avoid seeking dental care by children, so several communicative, advanced, and pharmacological interventions have been developed to manage children’s anxious and cooperative behaviors. Aim: To evaluate the effectiveness of tell–show–do (TSD), tell–play–do (TPD), and ask–tell–ask (ATA) behavioral modification techniques among 4–8 years old coming for a restorative treatment. Materials and Methods: Thirty children aged 4–8 years were enrolled in the study and randomly allocated to three groups, 10 children in each group. Group A: Those to receive restorative treatment by the behavior modification technique (BMT) of TSD; Group B: Those to receive restorative treatment by BMT of TPD; and Group C: Those to receive restorative treatment by BMT of ATA. Evaluation: Each child’s heart rate was monitored before, during, and after the entire treatment with a pulse oximeter. The oximeter was clipped to the thumb of the child’s left hand. Furthermore, Frankel Behavioral Rating Scale was to be monitored before, during, and after the procedure. Results: TPD technique is more efficient than TSD and ATA to control 4–8-year-old children’s anxiety and achieve cooperative behavior during dental treatment. Conclusion: TPD is a technique worth practicing in pediatric dentistry. The dentist should consider the cognitive development of the patient to communicate effectively for developing sound rapport and trust. Each dental visit should be designed to receive proper behavioral guidance techniques such as TPD, TSD, and modeling; these can help the child to develop a positive attitude toward oral health.
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6

Kurczewska, Ewa, Ewa Ferensztajn-Rochowiak, Anna Jasińska-Mikołajczyk, Maria Chłopocka-Woźniak, and Janusz K. Rybakowski. "Augmentation of Pharmacotherapy by Sleep Deprivation with Sleep Phase Advance in Treatment-Resistant Depression." Pharmacopsychiatry 52, no. 04 (September 10, 2018): 186–92. http://dx.doi.org/10.1055/a-0695-9138.

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Abstract Introduction The aim was to assess the efficacy of total sleep deprivation (TSD) with sleep phase advance (SPA) in treatment-resistant depression (TRD) and associated biochemical factors. Methods We studied nine males and 12 females, aged 49±14 years, with treatment-resistant unipolar or bipolar depression, receiving antidepressant and mood-stabilizing drugs. The four-day schedule included single TSD and three consecutive nights with SPA. Biochemical markers were measured on the day before and on 1st, 7th and 14th day after the TSD. Results Ten subjects met criteria for response, defined as a reduction of ≥50% in the Hamilton Depression Rating Scale, on the 14th day. Concentrations of cortisol at baseline were lower in responders, and they decreased during therapy in both groups. In responders, there was an increase of interleukin-10 (IL-10) and IL-1β on the 14th day. Discussion Our preliminary study demonstrated the efficacy of pharmacotherapy augmentation by TSD and SPA in half of the patients with TRD. The main biochemical factors related to clinical response included status of cortisol and increase in IL-10 and IL-1β levels.
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7

Kurczewska, Ewa, Ewa Ferensztajn-Rochowiak, Maria Chłopocka-Woźniak, and Janusz Rybakowski. "Sleep deprivation with sleep phase advance in treatment-resistant depression therapy in relation to features of circadian rhythm and temperament – a pilot study." Pharmacotherapy in Psychiatry and Neurology 34, no. 4 (January 8, 2019): 249–62. http://dx.doi.org/10.33450/fpn.2019.01.001.

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Objectives. The efficacy of pharmacotherapy augmentation by total sleep deprivation (TSD) with sleep phase advance (SPA) was evaluated in patients with treatment-resistant depression (TRD). The study examined the relationship between chronotype, affective temperaments and clinical improvement resulting from the treatment. Material and methods. The study group comprised of 30 persons with treatment-resistant unipolar (n = 15) or bipolar (n = 15) depression aged 52 ± 12 years (17 women and 13 men). TSD and three consecutive nights with SPA were used during pharmacotherapy. Severity of depression was determined using the Hamilton Depression Rating Scale (HDRS). All patients were assessed using the Composite Scale of Morningness (CSM) and Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Auto-questionnaire (TEMPS-A). Results. Clinical response, defined as a reduction in the severity of depression by ≥ 50% in HDRS compared to the baseline score, lasting until the end of the study (14 days), was obtained in 16 out of 30 patients with TRD. There was found no significant correlation between clinical improvement, chronotype and affective temperaments. Conclusions. TSD with SPA proved to be an effective method of pharmacotherapy augmentation in over half of the patients with TRD. The relationship between chronotype, affective temperaments and the clinical response to chronotherapy of depression requires further research.
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8

Shin, Eun-Sun, Mi-Jeong Yang, Kyung Hwa Jung, Eun-Ju Kwon, Jae Sung Jung, Seur Kee Park, Jungho Kim, Han Dae Yun, and Hoon Kim. "Influence of the Transposition of the Thermostabilizing Domain of Clostridium thermocellum Xylanase (XynX) on Xylan Binding and Thermostabilization." Applied and Environmental Microbiology 68, no. 7 (July 2002): 3496–501. http://dx.doi.org/10.1128/aem.68.7.3496-3501.2002.

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ABSTRACT A xylanase gene, xynX, of Clostridium thermocellum had one thermostabilizing domain (TSD) between the signal peptide sequence and the catalytic domain (CD). The TSD of a truncated xylanase gene, xynX′TSD-CD, was transpositioned from the N terminus to the C terminus of the CD by overlapping PCRs, and a modified product, xynX′CD-TSD, was constructed. XynX′TSD-CD had a higher optimum temperature (70°C versus 65°C) and was more thermostable (residual activity of 68% versus 46% after a 20-min preincubation at 70°C) than the one without the TSD, XynX′CD. However, the domain-transpositioned enzyme, XynX′CD-TSD, showed a lower optimum temperature (30°C) and thermostability (20%) than XynX′CD. Both XynX′TSD-CD and XynX′CD-TSD showed significantly higher binding capacity toward xylan than XynX′CD, and the domain transposition did not cause any change in the binding ability. XynX′TSD-CD and XynX′CD-TSD also showed considerable binding to lichenan but not to carboxymethyl cellulose and laminarin. XynX′TSD-CD and XynX′CD-TSD had higher activities for insoluble xylan than XynX′CD, while XynX′CD was more active against soluble xylan than XynX′TSD-CD and XynX′CD-TSD. These results indicate that the TSD of XynX has dual functions, xylan binding and thermostabilization, and the domain should also be classified as a xylan-binding domain (XBD). The binding capacity of the XBD was not affected by domain transpositioning within the gene.
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9

Lian, Jie, Lin Xu, Tao Song, Ziyi Peng, Zheyuan Zhang, Xin An, Shufang Chen, Xiao Zhong, and Yongcong Shao. "Reduced Resting-State EEG Power Spectra and Functional Connectivity after 24 and 36 Hours of Sleep Deprivation." Brain Sciences 13, no. 6 (June 14, 2023): 949. http://dx.doi.org/10.3390/brainsci13060949.

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Total sleep deprivation (TSD) leads to cognitive decline; however, the neurophysiological mechanisms underlying resting-state electroencephalogram (EEG) changes after TSD remain unclear. In this study, 42 healthy adult participants were subjected to 36 h of sleep deprivation (36 h TSD), and resting-state EEG data were recorded at baseline, after 24 h of sleep deprivation (24 h TSD), and after 36 h TSD. The analysis of resting-state EEG at baseline, after 24 h TSD, and after 36 h TSD using source localization analysis, power spectrum analysis, and functional connectivity analysis revealed a decrease in alpha-band power and a significant increase in delta-band power after TSD and impaired functional connectivity in the default mode network, precuneus, and inferior parietal lobule. The cortical activities of the precuneus, inferior parietal lobule, and superior parietal lobule were significantly reduced, but no difference was found between the 24 h and 36 h TSD groups. This may indicate that TSD caused some damage to the participants, but this damage temporarily slowed during the 24 h to 36 h TSD period.
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10

Derardja, Ala eddine, and Malika Barkat. "Effect of traditional sun-drying and oven-drying on carotenoids and phenolic compounds of apricot (Prunus armeniaca L.)." North African Journal of Food and Nutrition Research 3, no. 6 (October 10, 2019): 186–94. http://dx.doi.org/10.51745/najfnr.3.6.186-194.

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Background: The indubitable role of phytochemicals such as carotenoids and phenolic compounds in human health has prompted the researchers to study the factors affecting the stability and the availability of these compounds. Aims: This study investigates the effect of two drying processes; oven-drying (OD) and traditional sun-drying (TSD) on carotenoids and phenolic compounds of apricots. Material and Methods: OD was performed at 65°C, and TSD was performed by direct exposure of apricot to sunlight at daytime temperatures around 40°C and relative humidity between 25 and 35%, following an Algerian traditional method of drying. Carotenoids and phenolic compounds were extracted, and then total carotenoids (TC), total phenolic compounds (TPC), total flavonoids (TF) and total tannins (TT) were spectrophotometrically quantified. The free radical scavenging activity (FRSA) of the phenolic extracts was measured by the DPPH method. Results: Carotenoids and phenolic compounds were significantly affected by both drying methods. OD decreased TC and TT by 44% and 12%, respectively, and increased TPC and TF by 4%. TDS affected negatively all the measured components, where TC, TPC, TF, and TT decreased by 67%, 15%, 43%, and 36%, respectively. However, the highest FRSA was reported for the TSD apricots (40%) followed by OD apricots (36%), and fresh apricots (32%). Conclusions: The effect of drying on apricot antioxidants depends on the applied drying method and the studied component. The direct sunlight exposure and the duration of drying condemned TSD to be more harmful on carotenoids and phenolic compounds compared to OD, where carotenoids where more fragile during TSD. In addition, OD improved the content of phenolic compounds by improving their extractability. However, TSD apricots seem to be a better source of free radical scavenging compounds. Keywords: Apricot, traditional sun-drying, oven-drying, carotenoids, phenolic compounds.
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11

Pasetes, Lauren, Kathleen Rosendahl-Garcia, and Namni Goel. "0173 Baseline Actigraphic Sleep Measures Predict Cardiovascular Responses to Sleep Deprivation and Psychological Stress." SLEEP 47, Supplement_1 (April 20, 2024): A74—A75. http://dx.doi.org/10.1093/sleep/zsae067.0173.

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Abstract Introduction We determined whether baseline sleep measures the night before total sleep deprivation (TSD) predicted cardiovascular (CV) responses to TSD and to TSD and psychological stress. Methods We conducted a five-day experiment under controlled conditions in thirty-two healthy adults (ages 27-53; 14 females). During this experiment, CV measures were collected via echocardiography or blood pressure monitor at four assessment time points: 1) after two baseline 8h time in bed (TIB) nights (B1, B2); 2) in the morning of TSD (TSD AM; after 25h of TSD); 3) in the evening of TSD following a modified Trier Social Stress Test, which induced psychological stress (TSD PM; after 34h of TSD); and 4) after two recovery nights of 8-10h TIB. Seated stroke volume (SV), heart rate (HR), cardiac index (CI), left ventricular ejection time (LVET), systemic vascular resistance index (SVRI), mean arterial pressure (MAP), and systolic and diastolic blood pressure (SBP and DBP) were collected. Wrist actigraphy (Actiwatch Spectrum) assessed sleep indices during the second baseline night (B2) including sleep duration, sleep onset latency (SOL), wake after sleep onset (WASO), sleep efficiency (SE), percent sleep, and the timing of sleep onset, offset, and midpoint. Pearson’s correlations assessed relationships between B2 sleep metrics and TSD AM and TSD PM CV responses (p≤0.05 was significant). Results Higher WASO during baseline was significantly associated with lower SV (r=−0.374; r2=0.140) and higher SVRI (r=0.358; r2=0.128) during the TSD evening. By contrast, there were inverse relationships for percent sleep and SE during baseline, whereby these metrics were significantly associated with higher SV and lower SVRI during the TSD evening (r:−0.398-0.387; r2:0.126-0.159). In addition, a later sleep offset during baseline was significantly associated with higher MAP, SBP, and DBP during the morning and the evening of TSD (r:0.391-0.453; r2:0.153-0.205). Conclusion Our novel results found that actigraphic sleep metrics the night before TSD predicted CV responses in healthy adults, particularly during TSD and psychological stress in the evening. Thus, WASO, percent sleep, SE, and sleep offset timing during fully rested conditions are possible predictors and biomarkers for assessing the adverse cardiovascular responses to TSD and psychological stress. Support (if any) NASA grants NNX14AN49G and 80NSSC20K0243 (NG)
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Cheng, Qian Yu, Ya Fei Liu, Ze Yu Chen, Shan Shan Hu, Balaji Raghothamachar, Michael Dudley, Vladimir Pushkarev, et al. "Investigating Dislocation Arrays Induced by Seed Scratches during PVT 4H-SiC Crystal Growth Using Synchrotron X-Ray Topography." Defect and Diffusion Forum 434 (August 22, 2024): 71–80. http://dx.doi.org/10.4028/p-irzu7d.

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The influence of seed preparation on crystal defect generation is studied by investigating the effect of damage from surface scratches not completely removed during polishing on the seed crystal on the nucleation and evolution of dislocation arrays. Synchrotron X-ray topography is conducted on several wafers sliced from a PVT-grown 4H-SiC boule. Topographic results in conjunction with ray tracing simulation reveal the generation of TSD/TMD and TED arrays associated with the scratches in the newly grown wafer adjacent to the seed. Configuration transformation of those arrays is observed as these opposite-signed dislocation pairs composing the arrays were affected by the overgrowth of macro-steps when propagating into the newly grown crystal.
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13

Isshiki, Toshiyuki, and Masaki Hasegawa. "Study on Formation of Dislocation Contrast in 4H-SiC Wafer in Mirror Projection Electron Microscopy Image." Materials Science Forum 821-823 (June 2015): 307–10. http://dx.doi.org/10.4028/www.scientific.net/msf.821-823.307.

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A mirror projection electron microscopy (MPJ), non destructive, high spatial resolution and high throughput method, is useful for defect inspection in silicon carbide (SiC) wafer. Previously, it was demonstrate that three type of typical dislocations in 4H-SiC, threading screw dislocation (TSD), threading edge dislocation (TED) and basal plane dislocations (BPD) can be identified in MPJ image. Origin of the contrast of dislocations in MPJ image was revealed by observation of the same wafer at as-grown and after CMP processing. Streak of TSD spot is due to surface morphology, and the contrast of BPD isn’t due to surface morphology but due to charging on dislocation line.
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14

Yin, DengKe, ZhuQing Liu, DaiYin Peng, Ye Yang, XiangDong Gao, Fan Xu, and Lan Han. "Serum Containing Tao-Hong-Si-Wu Decoction Induces Human Endothelial Cell VEGF Production via PI3K/Akt-eNOS Signaling." Evidence-Based Complementary and Alternative Medicine 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/195158.

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Tao-Hong-Si-Wu decoction (TSD) is a famous traditional Chinese medicine (TCM) and widely used for ischemic disease in China. TSD medicated serum was prepared after oral administration of TSD (1.6 g/kg) twice a day for 3 days in rats. TSD medicated serum induced human umbilical vein endothelial cells (HUVECs) proliferation, VEGF secretion, and nitric oxide (NO) production. These promoted effects of TSD were partly inhibited by treatment with PI3K inhibitor (LY294002) or eNOS inhibitor (L-NAME), respectively, and completely inhibited by treatment with LY294002 and L-NAME simultaneously. Western blot analysis findings further indicated that TSD medicated serum upregulated p-Akt and p-eNOS expressions, which were significantly inhibited by LY294002 or L-NAME and completely inhibited by both LY294002 and L-NAME; these results indicated that TSD medicated serum induced HUVECs VEGF expression via PI3K/Akt-eNOS signaling. TSD medicated serum contains hydroxysafflor yellow A, ferulic acid, and ligustilide detected by UPLC with standards, so these effect of TSD medicated serum may be associated with these three active compounds absorbed in serum.
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15

Shrestha, Shivesh, Samer W. Katicha, Gerardo W. Flintsch, and Senthilmurugan Thyagarajan. "Application of Traffic Speed Deflectometer for Network-Level Pavement Management." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 40 (April 20, 2018): 348–59. http://dx.doi.org/10.1177/0361198118758675.

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In this paper, the traffic speed deflectometer (TSD), a device used for network level structural evaluation, is assessed. TSD testing was performed in nine states on a total of 5,928 miles (some repeated) during three time periods: November 2013, May to July 2014, and June to September 2015. This paper presents (1) the results of repeatability and comparison of the TSD with the falling weight deflectometer (FWD), (2) the results of the comparison of TSD measurements with typical pavement management system (PMS) data, and (3) an approach that can be implemented by State Highway Agencies (SHAs) to incorporate indices derived from TSD data into their PMS decision-making process. The results show that repeated TSD measurements follow similar trends and the TSD measurements and FWD measurements on the same pavement sections follow similar trends as well. Comparing TSD measurements with PMS surface condition data confirmed that the TSD provided valuable information about the structural condition of the tested pavement sections that cannot be derived from the already available pavement surface condition as part of an agency’s PMS. An example of how TSD information can be used to refine the triggered maintenance treatment category as part of a network-level PMS analysis is presented for a roughly 75-mile section of I-81 south in Virginia.
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Péntek, Máté, Andreas Riedl, Kai-Uwe Bletzinger, and Felix Weber. "Investigating the Vibration Mitigation Efficiency of Tuned Sloshing Dampers Using a Two-Fluid CFD Approach." Applied Sciences 12, no. 14 (July 12, 2022): 7033. http://dx.doi.org/10.3390/app12147033.

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The efficiency of a Tuned Sloshing Damper (TSD) when mitigating wind-induced structural vibrations is investigated. We assessed the performance in terms of peak structural displacements and accelerations, compared to that of the Tuned Mass Damper (TMD). One load scenario considers oncoming gusts due to natural turbulence, whereas the other assumes predominant vortex shedding at a low turbulence intensity. The known optimum tuning rules for TSDs and TMDs were adopted. We combined numerical models for fluids and structures to simulate the dynamic effects caused by wind loading. A two-fluid Computational Fluid Dynamics (CFD) approach was used for the realistic simulation of the TSD. The interaction between the flow, the structural behavior and the added devices was captured. All of these computational methods and respective models represent the necessary components of a modular and flexible simulation environment. The study demonstrates that this workflow is suited to model the inclusion of TSDs and TMDs, as well as to capture the effect of transient wind at full scale. We specifically used it to quantify the efficiency of added dampers. The process highlights challenges in properly tuning a TSD and its reduced efficiency compared to that of a TMD. Such an outcome is attributed to the water mass and potential added damping only being partially activated. The computational framework promises the ability to improve such designs by enabling numerical optimization for better efficiency.
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Pasetes, Lauren, Kathleen Rosendahl-Garcia, and Namni Goel. "0179 Cardiovascular Responses to Sleep Deprivation and Psychological Stress Predict Actigraphic Sleep During Recovery." SLEEP 47, Supplement_1 (April 20, 2024): A77. http://dx.doi.org/10.1093/sleep/zsae067.0179.

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Abstract Introduction We assessed whether cardiovascular (CV) responses to total sleep deprivation (TSD) and to TSD and psychological stress predicted sleep measures during that night’s recovery. Methods Thirty-two healthy adults (ages 27-53; 14 females) participated in a five-day experiment under controlled conditions. During this experiment, CV measures were collected via blood pressure monitor or echocardiography at four assessment time points: 1) after two baseline 8h time in bed (TIB) nights; 2) in the morning of TSD (TSD AM; after 25h of TSD); 3) in the evening of TSD following a modified Trier Social Stress Test, which induced psychological stress (TSD PM; after 34h of TSD); and 4) after two recovery nights (R1=10h TIB; R2=8h TIB). Seated heart rate (HR), cardiac index (CI), stroke volume (SV), systemic vascular resistance index (SVRI), left ventricular ejection time (LVET), systolic and diastolic blood pressure (SBP and DBP), and mean arterial pressure (MAP) were collected. Wrist actigraphy (Actiwatch Spectrum) assessed sleep measures during the first recovery night (R1) including the timing of sleep onset, offset, and midpoint, sleep duration, wake after sleep onset (WASO), sleep efficiency (SE), percent sleep, and sleep onset latency (SOL). Pearson’s correlations assessed relationships between TSD AM and TSD PM CV responses and R1 sleep indices (p< 0.05 was significant). Results Longer LVET in the morning and in the evening of TSD were significantly associated with longer sleep duration and later sleep offset during recovery (r: 0.386-0.471; r2: 0.149-0.222). In addition, longer LVET in the evening of TSD was significantly associated with higher WASO during recovery (r=0.385; r2=0.148). By contrast, lower HR in the morning (r=−0.449; r2=0.202) and in the evening (r=−0.499; r2=0.249) of TSD were significantly related to a later sleep offset during recovery. Conclusion To the best of our knowledge, this is the first demonstration that CV responses to TSD and to TSD and psychological stress, are reflected in the duration, quality, and timing of actigraphic sleep during the immediate recovery night in healthy adults. Overall, LVET and HR during sleep deprivation may be unique biomarkers for determining sleep responses during recovery that night. Support (if any) NASA grants NNX14AN49G and 80NSSC20K0243 (NG)
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Březina, František, Zdeněk Šindelář, Richard Pastorek, and Jan Lasovský. "Coordination compounds of nickel and cobalt with the Schiff base derived from thiosemicarbazide and diacetylmonooxime." Collection of Czechoslovak Chemical Communications 54, no. 12 (1989): 3238–44. http://dx.doi.org/10.1135/cccc19893238.

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Coordination compounds with the compositions [Ni(H2TSD)2]Cl2, [Co(H2TSD)2]Cl2, [NiH2O(TSD)], [CoH2O(TSD)] and [Co(TSD)(HTSD)].2H2O were prepared, where H2TSD = HON=C(CH3)C(CH3)=N.NH.CS.NH2. Cyclic voltammetry indicated that [NiH2O(TSD)] can be oxidized and reaction of this compound with bromine yielded the nickel compound with the composition [Ni(TSD)Br]. The properties of the ligand that make it useful for stabilizing the higher oxidation states of nickel are discussed.
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Yamazaki, E. M., K. M. Rosendahl-Garcia, L. E. MacMullen, A. J. Ecker, J. N. Kirkpatrick, and N. Goel. "0041 Heart Rate Variability Differs in Resilient vs. Vulnerable Adults from Total Sleep Deprivation and Psychological Stress and Predicts Cognitive Performance." Sleep 43, Supplement_1 (April 2020): A16—A17. http://dx.doi.org/10.1093/sleep/zsaa056.040.

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Abstract Introduction There are substantial individual differences (resilience and vulnerability) in neurobehavioral performance from psychosocial stress and sleep loss. However, the time course of heart rate variability (HRV) across baseline, total sleep deprivation (TSD), the combination of TSD + psychological stress, and recovery has not been investigated; in addition, it remains unknown whether HRV and blood pressure (BP) differ in resilient vs. vulnerable individuals and predict individual differences in cognitive performance. Methods Thirty-one healthy adults (ages 27–53; mean±SD, 35.4±7.1y; 14 females) participated in a five-day experiment consisting of two 8h time-in-bed (TIB) baseline nights, 39h TSD, and two 8h-10h TIB recovery nights. A modified Trier Social Stress Test (TSST) induced psychological stress on the TSD day. Systolic and diastolic BP and HRV (derived from echocardiographic R-R interval) were obtained at six time points (pre-study, baseline, during TSD, during TSD after the TSST, after recovery, and post-study). Cognitively resilient (n=15) and vulnerable (n=16) groups were defined by a median split on 10-minute Psychomotor Vigilance Test (PVT) TSD performance [total lapses (>500ms response time) and errors]. Repeated measures ANOVA and post-hoc comparisons corrected for multiple testing, examined BP and HRV across time points between groups. Results HRV showed a significant time*group interaction: while resilient individuals had significantly lower HRV at pre-study compared to vulnerable individuals, their HRV increased above that of vulnerable individuals with TSD and with TSD + psychological stress. By contrast, systolic and diastolic BP did not show significant time*group interactions and did not predict cognitive vulnerability during TSD. Conclusion HRV differed between resilient and vulnerable individuals across TSD, psychological stress and recovery sleep and predicted individual differences in cognitive performance, whereby lower HRV during full-rested conditions predicted resilience to TSD and TSD + psychological stress. HRV, but not BP, is a reliable biomarker of sleep deprivation, psychological stress, and neurobehavioral vulnerability. Support NASA NNX14AN49G.
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Goel, N., E. M. Yamazaki, L. E. MacMullen, and A. J. Ecker. "0265 Cortisol and C-Reactive Protein Fail to Predict Individual Differences in Neurobehavioral Performance Responses to Total Sleep Deprivation and Psychological Stress." Sleep 43, Supplement_1 (April 2020): A101. http://dx.doi.org/10.1093/sleep/zsaa056.263.

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Abstract Introduction Individuals show marked differential vulnerability in neurobehavioral deficits from psychosocial stress and sleep deprivation. Although changes in salivary cortisol and C-reactive protein (CRP) typically occur across total sleep deprivation (TSD) and recovery sleep, whether these biological markers during fully rested conditions predict individual differences in cognitive performance during TSD and stress remains unknown. Methods Thirty-one healthy adults (ages 27–53; mean ± SD, 35.4 ± 7.1y; 14 females) participated in a five-day experiment consisting of two 8h time-in-bed (TIB) baseline nights, followed by 39h TSD, and two 8h-10h TIB recovery nights. A modified Trier Social Stress Test (TSST) was conducted on the day of TSD to induce psychological stress. Salivary cortisol and CRP from blood were obtained at six time points during the study (pre-study, baseline, during TSD, during TSD after the TSST, after recovery, and post-study). A median split of TSD performance [total lapses (>500 ms response time) and errors] on the 10-minute Psychomotor Vigilance Test (PVT) defined cognitively resilient (n=15) and cognitively vulnerable (n=16) groups. Repeated measures ANOVA and post-hoc comparisons corrected for multiple testing, examined cortisol and CRP across time points between groups. Results In both cognitively resilient and vulnerable individuals, cortisol increased with TSD compared to baseline in the morning and decreased with TSD + psychological stress in the afternoon compared to TSD alone. By contrast, there were no significant changes in CRP levels throughout the experiment. In addition, there were no significant time*group interactions in cortisol or CRP levels. Conclusion Salivary cortisol increased with TSD compared to baseline and showed a time-of-day effect with stress during TSD. Notably, cortisol and CRP did not differ between cognitively resilient and vulnerable individuals across TSD, psychological stress or recovery sleep and thus are not reliable biomarkers for predicting performance under these conditions. Support NASA NNX14AN49G.
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Goel, Namni, and Lauren Pasetes. "0172 Predictive Relationships Between Baseline and Recovery Sleep and Neurobehavioral Measures During Sleep Deprivation." SLEEP 47, Supplement_1 (April 20, 2024): A74. http://dx.doi.org/10.1093/sleep/zsae067.0172.

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Abstract Introduction We investigated whether baseline sleep measures derived from actigraphy the night before total sleep deprivation (TSD) predicted cognitive performance and subjective sleepiness and fatigue during TSD. We also investigated whether these measures during TSD predicted that night’s recovery sleep. Methods Thirty-two adults (ages 27-53;14 females) participated in a five-day experiment under controlled conditions comprised of two baseline 8h time in bed (TIB) nights (B1, B2), approximately 39h of TSD, and two recovery nights of 8-10h TIB (R1=10h, R2=8h). Neurobehavioral measures including the Digit Symbol Substitution Test (DSST), Digit Span (DS), the 10-minute Psychomotor Vigilance Test (PVT), the Karolinska Sleepiness Scale, and the Profile of Mood States Fatigue scale were collected at 0400h, 1130h, and 1730h during TSD. During the second baseline night (B2) and the first recovery night (R1), wrist actigraphy (Actiwatch Spectrum) assessed sleep indices including sleep duration, sleep onset latency (SOL), wake after sleep onset (WASO), sleep efficiency (SE), percent sleep, and the timing of sleep onset, offset, and midpoint. Pearson’s correlations determined relationships between B2 sleep and TSD neurobehavioral measures and between TSD neurobehavioral and R1 sleep measures (p< 0.05 was significant). Results Greater SE at baseline was significantly associated with less subjective sleepiness during TSD (r=−0.415;r2=0.172), and a later sleep onset (r=−0.409;r2=0.167) and a later midpoint (r=−0.376; r2=0.142) were significantly correlated with less subjective fatigue during TSD. Higher DSST scores during TSD were significantly associated with shorter duration, greater SOL, and a later sleep onset during recovery (r:−0.473-0.547; r2:0.172-0.299). Similarly, higher DS scores significantly correlated with later sleep onset (r=0.370; r2=0.137). Fewer PVT lapses during TSD were significantly associated with shorter duration, higher SE, lower WASO, higher percent sleep, and an earlier sleep offset during recovery (r:−0.417-0.489; r2:0.136-0.239). Conclusion Our novel findings demonstrated that measures of sleep continuity and timing the night before TSD predicted resilience to subjective sleepiness and fatigue, but not cognitive performance during TSD. By contrast, cognitive but not subjective performance resilience during TSD predicted that night’s recovery sleep duration, continuity, and timing. Thus, actigraphic measures uniquely predict subjective responses to TSD and reflect cognitive performance responses during sleep loss. Support (if any) NASA grants NNX14AN49G and 80NSSC20K0243 (NG)
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Martin, Dianna C., Brian L. Mark, Barbara L. Triggs-Raine, and Marvin R. Natowicz. "Evaluation of the Risk for Tay-Sachs Disease in Individuals of French Canadian Ancestry Living in New England." Clinical Chemistry 53, no. 3 (March 1, 2007): 392–98. http://dx.doi.org/10.1373/clinchem.2006.082727.

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Abstract Background: The assessment of risk for Tay-Sachs disease (TSD) in individuals of French Canadian background living in New England is an important health issue. In preliminary studies of the enzyme-defined carrier frequency for TSD among Franco-Americans in New England, we found frequencies (1:53) higher than predicted from the incidence of infantile TSD in this region. We have now further evaluated the risk for TSD in the Franco-American population of New England. Methods: Using a fluorescence-based assay for β-hexosaminidase activity, we determined the carrier frequencies for TSD in 2783 Franco-Americans. DNA analysis was used to identify mutations causing enzyme deficiency in TSD carriers. Results: We determined the enzyme-defined carrier frequency for TSD as 1:65 (95% confidence interval 1:49 to 1:90). DNA-based analysis of 24 of the enzyme-defined carriers revealed 21 with sequence changes: 9 disease-causing, 4 benign, and 8 of unknown significance. Six of the unknowns were identified as c.748G>A p.G250S, a mutation we show by expression analysis to behave similarly to the previously described c.805G>A p.G269S adult-onset TSD mutation. This putative adult-onset TSD c.748G>A p.G250S mutation has a population frequency similar to the common 7.6 kb deletion mutation that occurs in persons of French Canadian ancestry. Conclusions: We estimate the frequency of deleterious TSD alleles in Franco-Americans to be 1:73 (95% confidence interval 1:55 to 1:107). These data provide a more complete data base from which to formulate policy recommendations regarding TSD heterozygosity screening in individuals of French Canadian background.
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Moritani, Tatsuru, Hayato Usui, Tadahiko Morinaga, Hideyuki Sato, and Satomi Onoue. "Cyclosporine A-Loaded Ternary Solid Dispersion Prepared with Fine Droplet Drying Process for Improvement of Storage Stability and Oral Bioavailability." Pharmaceutics 15, no. 2 (February 8, 2023): 571. http://dx.doi.org/10.3390/pharmaceutics15020571.

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This study aimed to develop a cyclosporine A (CsA)-loaded ternary solid dispersion (tSD/CsA) to improve the storage stability of a solid dispersion (SD) system and the oral absorbability of CsA. Hydroxypropyl cellulose (HPC) and hydroxypropyl methylcellulose acetate succinate (HPMCAS) were selected as carrier materials of tSD, and tSD/CsA was prepared with a fine droplet drying process, a powderization technology that employs an inkjet head. The physicochemical properties of tSD/CsA were evaluated in terms of morphology, storage stability, dissolution behavior, and mucoadhesive property. After the oral administration of CsA samples (10 mg-CsA/kg) to rats, the plasma concentration of CsA was monitored to estimate oral absorbability. tSD/CsA comprised uniform shriveled particles with a diameter of 3.4 mm and span factor of 0.4, which is a parameter to estimate the particle size distribution. Although HPC-based binary SD showed marked aggregation of the particles after storage under 40 °C/75% relative humidity, there were no significant aggregations of tSD/CsA, due to the relatively low hygroscopic property of HPMCAS. The pH-dependent release of CsA with improved dissolution was observed in tSD/CsA. In the in vitro mucoadhesive evaluation using a mucin disk, tSD/CsA exhibited a better mucoadhesive property than HPC-based SD, possibly leading to prolonged retention of tSD particles in the gastrointestinal tract after oral administration. Orally-dosed tSD/CsA in rats resulted in significantly improved oral absorption of CsA, as evidenced by a 27-fold higher bioavailability than amorphous CsA. tSD/CsA may be a promising dosage option to improve the storage stability of a SD system and the biopharmaceutical properties of CsA.
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Nielsen, Christoffer P. "Visco-Elastic Back-Calculation of Traffic Speed Deflectometer Measurements." Transportation Research Record: Journal of the Transportation Research Board 2673, no. 12 (July 23, 2019): 439–48. http://dx.doi.org/10.1177/0361198118823500.

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The traffic speed deflectometer (TSD) has proven a valuable tool for network level structural evaluation. At the project level, however, the use of TSD data is still quite limited. An obstacle to the use of TSD at the project level is that the standard approaches to back-calculation of pavement properties are based on the falling weight deflectometer (FWD). The FWD experiment is similar, but not equivalent, to the TSD experiment, and therefore it is not straightforward to apply the traditional FWD back-calculation procedures to TSD data. In this paper, a TSD-specific back-calculation procedure is presented. The procedure is based on a layered linear visco-elastic pavement model and takes the driving speed of the vehicle into account. This is in contrast to most existing back-calculation procedures, which treat the problem as static and the pavement as purely elastic. The developed back-calculation procedure is tested on both simulated and real TSD data. The real TSD measurements exhibit significant effects of damping and visco-elasticity. The back-calculation algorithm is able to capture these effects and yields model fits in excellent agreement with the measured values.
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Lian, Jie, Lin Xu, Tao Song, Ziyi Peng, Xinxin Gong, Jie Chen, Xiao Zhong, Xin An, Shufang Chen, and Yongcong Shao. "Decreased Functional Connectivity of Brain Networks in the Alpha Band after Sleep Deprivation Is Associated with Decreased Inhibitory Control in Young Male Adults." International Journal of Environmental Research and Public Health 20, no. 5 (March 6, 2023): 4663. http://dx.doi.org/10.3390/ijerph20054663.

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Sleep deprivation leads to reduced inhibitory control in individuals. However, the underlying neural mechanisms are poorly understood. Accordingly, this study aimed to investigate the effects of total sleep deprivation (TSD) on inhibitory control and their neuroelectrophysiological mechanisms from the perspective of the time course of cognitive processing and brain network connectivity, using event-related potential (ERP) and resting-state functional connectivity techniques. Twenty-five healthy male participants underwent 36 h of TSD (36-h TSD), completing Go/NoGo tasks and resting-state data acquisition before and after TSD; their behavioral and electroencephalogram data were recorded. Compared to baseline, participants’ false alarms for NoGo stimuli increased significantly (t = −4.187, p < 0.001) after 36-h TSD. ERP results indicated that NoGo-N2 negative amplitude increased and latency was prolonged (t = 4.850, p < 0.001; t = −3.178, p < 0.01), and NoGo-P3 amplitude significantly decreased and latency was prolonged (t = 5.104, p < 0.001; t = −2.382, p < 0.05) after 36-h TSD. Functional connectivity analysis showed that the connectivity of the default mode and visual networks in the high alpha band was significantly reduced after TSD (t = 2.500, p = 0.030). Overall, the results suggest that the negative amplitude increase in N2 after 36-h TSD may reveal that more attention and cognitive resources are invested after TSD; the significant decrease in P3 amplitude may indicate the impairment of advanced cognitive processing. Further functional connectivity analysis indicated impairment of the brain’s default mode network and visual information processing after TSD.
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Prence, Elizabeth M., Cheryl A. Jerome, Barbara L. Triggs-Raine, and Marvin R. Natwicz. "Heterozygosity for Tay-Sachs and Sandhoff Diseases among Massachusetts Residents with French Canadian Background." Journal of Medical Screening 4, no. 3 (September 1997): 133–36. http://dx.doi.org/10.1177/096914139700400304.

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Objectives— The frequency of Tay-Sachs disease (TSD) heterozygosity is increased among French Canadians in eastern Quebec. A large proportion of the New England population has French Canadian heritage; thus, it is important to determine if they too are at increased risk for TSD heterozygosity. This prospective study was designed to assess the TSD heterozygote frequency among people with French Canadian background living in Massachusetts. A simultaneous screen for heterozygosity for Sandhoff disease, a related genetic disorder, was also undertaken. Methods— 1260 non-pregnant subjects of French Canadian background were included in the study, β hexosaminidase activity was measured in blood samples, and results were evaluated for TSD and Sandhoff disease heterozygosity. Samples from the TSD heterozygotes were also subjected to mutation analysis. Results— Of the 1260 samples studied, 22 (1 in 57; CI 1 in 41, 1 in 98) were identified as TSD heterozygotes by enzymatic analyses and 11 subjects (1 in 114; CI 1 in 72,1 in 280) were identified as Sandhoff disease heterozygotes. Three of the 22 TSD heterozygotes were found to have benign pseudodeficiency mutations, resulting in a maximum TSD heterozygote frequency of 19 in 1260 (1 in 66; CI 1 in 46, 1 in 120). Together, these data provide a maximum frequency of heterozygosity for TSD or Sandhoff disease of 30 in 1260 (1 in 42; CI 1 in 31, 1 in 64) in this population. Conclusions— Simultaneous screening for TSD and Sandhoff disease heterozygosity by assay of β hexosaminidases A and B activities provides a possible method for use with subjects of French Canadian background. The relevance of some of the novel mutations identified in this group needs further study. However, the comparatively high combined frequency of TSD and Sandhoff disease heterozygosity indicates a need for discussion regarding the appropriateness of carrier testing for these disorders for persons of French Canadian background in Massachusetts.
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Yamazaki, E. M., K. M. Rosendahl-Garcia, L. E. MacMullen, A. J. Ecker, J. N. Kirkpatrick, and N. Goel. "0042 Stroke Volume and Cardiac Index are Differentially Altered by Total Sleep Deprivation and Psychological Stress in Resilient vs. Vulnerable Individuals and Predict Cognitive Performance." Sleep 43, Supplement_1 (April 2020): A17. http://dx.doi.org/10.1093/sleep/zsaa056.041.

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Abstract Introduction Individuals show robust resilience and vulnerability in neurobehavioral performance to sleep loss and stress. For the first time, we investigated the time course of two cardiovascular measurements, stroke volume (SV) and cardiac index (CI), both derived from echocardiography, across baseline, total sleep deprivation (TSD), the combination of TSD+psychological stress, and recovery. We also determined whether these variables differ in resilient vs. vulnerable individuals and whether they predict differential vulnerability in cognitive performance. Methods Thirty-one healthy adults (ages 27–53; mean±SD, 35.4±7.1y; 14 females) participated in a five-day experiment consisting of two 8h time-in-bed (TIB) baseline nights, 39h TSD, and two 8h-10h TIB recovery nights. A modified Trier Social Stress Test (TSST) was conducted on the TSD day to induce psychological stress. Echocardiographic measures of SV and CI were obtained at six time points (pre-study, baseline, during TSD, during TSD after the TSST, after recovery, and post-study). A median split of TSD performance [total lapses (&gt;500 ms response time) and errors] on the 10-minute Psychomotor Vigilance Test (PVT), defined cognitively resilient (n=15) and vulnerable (n=16) groups. Repeated measures ANOVA and post-hoc comparisons corrected for multiple testing, examined SV and CI across time points between groups. Results There was a significant time*group interaction for SV: cognitively resilient individuals had greater SV during the five-day experiment. In addition, in both resilient and vulnerable individuals, SV increased with TSD and with TSD+psychological stress compared with baseline. Like SV, there was a significant time*group interaction for CI: resilient individuals had greater CI at all points of the experiment. Conclusion SV and CI differed between resilient and vulnerable individuals across TSD, psychological stress and recovery sleep. Greater SV and greater CI at baseline predicted resilience to TSD and TSD+psychological stress. CI and SV are novel physiological biomarkers of sleep loss, stress, and individual differences in cognitive performance. Support NASA NNX14AN49G.
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Skeiky, Lillian, Kirsie Lundholm, Sean Hovland, Paul Whitney, John Hinson, Hans Van Dongen, and Courtney Kurinec. "0064 Sleep Loss Affects Item and Source Memory Differentially as a Function of Serotonin Transporter (5-HTTLPR) Genotype." SLEEP 47, Supplement_1 (April 20, 2024): A29. http://dx.doi.org/10.1093/sleep/zsae067.0064.

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Abstract Introduction Remembering relationships between items (information) and the contexts (sources) in which they are framed is crucial for everyday functioning. Total sleep deprivation (TSD) impairs this ability, with evidence suggesting that TSD affects source memory even when items are remembered. Source memory deficits imply problems with associative memory, which relies on hippocampal functioning, known to be altered by TSD. Serotonin is highly expressed in the hippocampus, is influenced by TSD, and may be part of a mechanism by which TSD degrades source memory. We investigated the association between 5-HTTLPR, a functional length polymorphism of the human serotonin transporter gene (SLC6A4), and item and source memory during TSD. Methods N=34 healthy adults (ages 27.3±4.9y; 18 female) participated in a 4-day/3-night laboratory TSD study. Participants underwent 38h TSD, preceded and followed by 10h sleep opportunities. At baseline and 24h later during TSD, they completed an item/source memory task. Participants listened to a list of 60 words each presented by a male or female speaker (study phase). They were then tested for recognition of the words (items) out of 60 old and 60 new words presented visually, and were asked to identify the corresponding speakers (sources, male or female). Results The genotype distribution was in Hardy-Weinberg equilibrium (P=0.34), with 35.3% long/long, 41.2% long/short, 23.5% short/short. Mixed-effects ANOVA showed a significant adverse effect of TSD for both item recognition (P&lt; 0.001) and source recognition (P&lt; 0.001), where TSD degraded source memory even when item recognition was accurate. There were no 5-HTTLPR genotype effects on item memory. However, there was a significant main effect for genotype on source memory (P=0.019), and a genotype by TSD interaction (P=0.018). For accurately recognized items, source memory was largely preserved for the short/short genotype but impaired for carriers of the long allele, and especially the long/long genotype. Conclusion 5-HTTLPR genotype predicted source memory deficits from TSD, distinct from item memory deficits unaffected by genotype, which confirms that item and source memory deficits due to TSD are dissociable. Furthermore, TSD’s impact on binding of items and sources in memory may be mediated by hippocampal serotonin. Support (if any) NIH R21CA167691, WSU Anthony Marchionne and Foundry10 Bridge fellowships
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Gordijn, M. C. M., D. G. M. Beersma, A. L. Bouhuys, H. J. Korte, and R. H. van den Hoofdakker. "A longitudinal study of sleep deprivation responses in depression; The variability is highly related to diurnal mood variability." Acta Neuropsychiatrica 7, no. 2 (June 1995): 58–60. http://dx.doi.org/10.1017/s0924270800037583.

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Unequivocal results demonstrating a causal relationship between a disturbance in circadian rhythms and depression have not yet been reported (reviews). However, acute mood changes, such as the antidepressive effect of sleep deprivation, diurnal variations of mood and their interrelationship, are commonly put forward as evidence of the importance of circadian dysregulations in affective disorders. The purpose of the present study is to obtain more insight in the mechanisms underlying these mood changes. The results will be discussed in the context of a recently postulated non-chronobiological explanation.Earlier studies have suggested that the relationship between diurnal variation of mood and the response to total sleep deprivation (TSD) is clear and unambiguous: improvement of mood during the day prior to TSD (a positive diurnal variation) is followed by a positive response (mood improvement) to TSD, while no improvement or deterioration of mood during the day prior to TSD (a negative diurnal variation) may result in no, or even a negative, TSD response (for references see Van den Hoofdakker). However, these conclusions were based on the results from cross-sectional studies, comparing single TSD effects across individuals. Comparison of sleep deprivation effects within individuals, however, revealed that the course of mood during the day prior to TSD is irrelevant for the TSD response. Accordingly, a favourable response to TSD appeared to be related to the patient's propensity to show diurnal mood variations per se, irrespective of their direction.
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Xie, Zihuang, Yimin Zhu, Yijia Hu, Yao Ha, and Zhong Zhong. "A Statistical Prediction Model for Summer Precipitation in China Based on TSD Method and EOF Modes’ Time Coefficients." Sustainability 15, no. 14 (July 12, 2023): 10928. http://dx.doi.org/10.3390/su151410928.

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It is a challenge to improve the skill of seasonal precipitation prediction, because there are many factors affecting summer precipitation in China, which are found on different time scales and have complex interactions with each other. For these reasons, we establish a prediction model with the time-scale decomposition (TSD) method to investigate whether the TSD has an improving effect on the prediction skill of summer precipitation in China. Using this statistical model, the predictors and predictands will be separated into interannual and interdecadal time scales, after which Empirical Orthogonal Function (EOF) decomposition is performed on these two components, and their time coefficients are predicted, respectively. The hindcast cross-validation results show that the model without TSD has prediction skills only in some regions of East China and South China. Compared with the model without TSD, surprisingly, the model with TSD can significantly improve the prediction performance in more regions in China, such as Xinjiang Province and Northeast China. The anomaly correlation coefficients (ACC) between hindcast precipitation with TSD and observation are higher in most years than that without TSD. The results of the independent sample test show that the forecast model with TSD has a stable and gratifying prediction skill, and the averaged ACC is increased by more than 0.1.
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Rasemi Widayanti, Marcellina, and Irine Yunila Prastyawati. "Korelasi Usia Dengan Tekanan Darah Sistolik-Diastolik, Indeks Massa Tubuh, Kadar Kolestrol Pada Lansia." JURNAL KESEHATAN MERCUSUAR 6, no. 1 (April 30, 2023): 20–25. http://dx.doi.org/10.36984/jkm.v6i1.352.

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Penyakit degeneratif masih menjadi tantangan karena perkembangan lansia terus meningkat setiap tahunnya. Tujuan penelitian ini adalah mengetahui hubungan usia dengan tekanan darah sistolik-diastolik, indeks massa tubuh, kadar kolesterol di RT 3 RW 12 Kedung Anyar Surabaya. Desain penelitian adalah observasional analitik dengan pendekatan cross sectional, jumlah sampel 44 responden lansia Kedung Anyar Surabaya dan diuji menggunakan Pearson. Hasil menunjukkan jenis kelamin 68% perempuan. Usia rata-rata responden 53,66 tahun. Rata-rata Tekanan Darah Sistolik (TDS) responden adalah 133 mmHg. Nilai rata-rata Tekanan Darah Diastolik (TDD) adalah 84,95 mmHg. Indeks Massa Tubuh (IMT) rata-rata adalah 23,15 kg/m2. Kadar kolesterol rata-rata 185,86 mg/dl. Uji korelasi menunjukkan tidak ada hubungan antara umur dengan TSD, TDD, IMT dan kadar kolesterol. Saran dari penelitian ini adalah agar dilakukan observasi lanjutan secara berkala untuk mendeteksi masalah sindrom metabolik, sehingga dapat mengurangi masalah degeneratif dan meningkatkan kapasitas seseorang dengan memberikan edukasi tentang masalah kesehatan degeneratif.
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Finlay, Myles, Devon Hansen, Lillian Skeiky, and Hans Van Dongen. "332 Non-REM EEG Spectral Power at Baseline and After Total Sleep Deprivation in Individuals with Sleep-Onset Insomnia." Sleep 44, Supplement_2 (May 1, 2021): A133. http://dx.doi.org/10.1093/sleep/zsab072.331.

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Abstract Introduction The baseline non-REM sleep EEG of individuals with insomnia has been found to display increased spectral power at frequencies &gt;14Hz, which may reflect hyperarousal. There is some evidence in this population of reduced slow wave activity after total sleep deprivation (TSD), potentially indicating altered sleep homeostasis. We investigated non-REM sleep EEG spectra at baseline and after TSD in individuals with sleep-onset insomnia. Methods 10 individuals with sleep-onset insomnia and 5 healthy controls (ages 22-40y, 11 females) completed a 5-day laboratory study with an adaptation night, baseline night, assignment to 38h TSD (n=5 insomnia, n=5 control) or equivalent non-TSD control (n=5 insomnia), and recovery night. Sleep periods were 10h (22:00-08:00) with digital polysomnography (250Hz; Nihon Kohden). Following artifact rejection, 5s subepochs of the non-REM (stages N2, N3) sleep EEG (C3-M2 derivation) in baseline and recovery nights were subjected to spectral analysis. Spectra (0.2Hz bins) were averaged over subepochs in 30s epochs. Repeated-measures ANOVA compared baseline spectra between insomnia and controls, and baseline-recovery difference spectra between TSD insomnia, non-TSD insomnia, and TSD controls. Results Average non-REM sleep amount was 5.9 at baseline, increasing by 1.1h after TSD, with no differences between groups (p≥0.20). At baseline, the insomnia group showed increased power in theta/alpha (~4–12Hz), reaching significance in the lower spindle range, compared to controls (p&lt;0.05). As anticipated, no differences emerged between baseline and recovery nights in the non-TSD insomnia group. However, the TSD insomnia group showed increased delta (~1–3Hz) and theta/alpha (~6–10Hz) power (p&lt;0.05) during recovery. Healthy controls showed expected power increases in delta and lower spindle range, and decreases in upper spindle range (~14–15Hz), after TSD (p&lt;0.05). Conclusion Compared to healthy controls, individuals with sleep-onset insomnia showed increased non-REM sleep EEG power in the theta/alpha bands and low spindle frequency range, with further significant increases in theta/alpha in addition to delta power following TSD, despite small sample size. The increase in delta power following TSD was equivalent to that in healthy controls, suggesting no sleep homeostasis abnormality. Whether the elevated theta/alpha power may be related to hyperarousal is unclear. Support (if any) ONR grant N00014-13-C-0063
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Ellison, Alexandre, Erik Sörman, Björn Sundqvist, Björn Magnusson, Yu Yang, Jian Qiu Guo, Ouloide Goue, Balaji Raghothamachar, and Michael Dudley. "Mapping of Threading Screw Dislocations in 4H n-Type SiC Wafers." Materials Science Forum 858 (May 2016): 376–79. http://dx.doi.org/10.4028/www.scientific.net/msf.858.376.

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X-ray topography shows that selective KOH etching after CVD growth of n-type epilayers on highly N doped 4H SiC substrates can be used to reliably map pure and mixed Threading Screw Dislocations (TSD). The influence of the mapping grid density and the wafer position in the crystal on the average TSD density are investigated. A reliable mapping of TSD contributed to the development of 100mm SiC wafers with average TSD density down to 200 cm-2.
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Kant, Shashi. "The marginal cost of structural diversity of mixed uneven-aged hard maple forests." Canadian Journal of Forest Research 32, no. 4 (April 1, 2002): 616–28. http://dx.doi.org/10.1139/x02-001.

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Theoretical concepts pertaining to the marginal cost (MC) of the structural diversity of a forest stand are developed. A matrix growth model is estimated for mixed uneven-aged forest stands of hard maple (Acer saccharum Marsh.) from southern Ontario. The estimated growth model is used to derive the MC equations for the Shannon and the Simpson indices of total structural diversity (TSD), species diversity (SD), and tree-size diversity (TD). The effects of exclusion and inclusion of the opportunity cost (OC) on the MC of the TSD are compared. The contributions of SD and TD to the MC of the TSD are disaggregated. The MCs of TSD, SD, and TD for the Shannon and the Simpson indices are iso-elastic. The elasticity of the MC of the TSD for the inclusion of OC is greater than the elasticity of MC of the TSD for the exclusion of OC. The elasticities of MC of TSD, SD, and TD for the Shannon index are greater than the elasticities of MC of TSD, SD, and TD, respectively, for the Simpson index. The elasticities of MC of SD are smaller than the elasticities of MC of TD, for both indices. However, these results are specific to the hard maple forests of southern Ontario and cannot be generalized. Some general features of MC equations of structural diversity are discussed.
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Yin, Ying, Shufang Chen, Tao Song, Qianxiang Zhou, and Yongcong Shao. "Cognitive Load Moderates the Effects of Total Sleep Deprivation on Working Memory: Evidence from Event-Related Potentials." Brain Sciences 13, no. 6 (June 1, 2023): 898. http://dx.doi.org/10.3390/brainsci13060898.

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Purpose: The function of working memory (WM) is impaired by total sleep deprivation (TSD) and cognitive load. However, it is unclear whether the load modulates the effect of TSD on WM. We conducted a pilot study to investigate the effects of 36 h of TSD on WM under different load levels. Materials and methods: Twenty-two male students aged 18–25 years were enrolled, who underwent two types of sleep conditions (baseline and 36 h TSD), where they performed two N-back WM tasks (one-back task and two-back task) with simultaneous electroencephalography recordings. Results: Repeated measures analysis of variance (ANOVA) indicated that, with the increasing load, the reaction time increased and the accuracy decreased. After TSD, the correct number per unit time decreased. The significant interaction effect of the P3 amplitudes between the load level and the sleep condition showed that the reduction in the amplitude of P3 in the two-back task due to TSD was more obvious than that in the one-back task. Conclusions: Our results provided evidence for the moderation of load on the impairment of TSD on WM. The degree of TSD-induced impairment for a higher load was greater than that for a lower load. The current study provides new insights into the mechanisms by which sleep deprivation affects cognitive function.
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Johnsen, Clark, and Helen T. Ding. "Therapist self-disclosure: Let’s tackle the elephant in the room." Clinical Child Psychology and Psychiatry 26, no. 2 (February 11, 2021): 443–50. http://dx.doi.org/10.1177/1359104521994178.

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Therapist Self-Disclosure (TSD), the revealing of a therapist’s feelings, thoughts or personal information to a client, is an inevitable aspect of therapeutic relationships. However, despite its prevalence in clinical settings, we believe there is insufficient recognition and exploration of TSD in our work with children and adolescents. Because TSD is not often formally addressed during training, therapists across the spectrum of clinical child psychology and psychiatry are often left with the belief that disclosures are rare or inherently negative occurrences that should be avoided. As a byproduct, therapists often develop a blind spot to many disclosures that they make and are thus underprepared to navigate the complex decision-making process that surrounds TSD. In our article, we address the elephant in the room: that most therapists disclose in some form or other. In addressing this topic, we hope to encourage replacement of avoidance and silence with discourse and reflection around TSD occurrences. We explore developmental considerations pertinent to child and adolescent clients as well as suggest a framework for TSD decisions. We feel that improved supervision and clinical practice around TSD is a worthy and achievable aim that merits further recognition, consideration and educational focus.
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Miró, Elena, Carmen Cano, and Gualberto Buela-Casal. "Effects of Total Sleep Deprivation on Cardiovascular Parameters: An Absence of Biologically Significant Findings?" Journal of Psychophysiology 16, no. 2 (January 2002): 119–26. http://dx.doi.org/10.1027//0269-8803.16.2.119.

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Abstract The present study analyzes the variations of heart rate (HR) and systolic and diastolic blood pressure (SBP and DBP) during 60 h of total sleep deprivation (TSD). All variables were evaluated every 2 h in a resting condition, during the performance of a vigilance task. Thirty healthy volunteers (15 men and 15 women) from 18 to 24 years old participated in the experiment. The analyses of variance (ANOVAS) with repeated measures showed some modifications of HR and SBP mean values mainly marked by circadian oscillations. The circadian oscillations had a smaller amplitude for SBP than for HR. HR showed a slight decrease on the second night of TSD and a slight increase on the third day of TSD. SBP decreased during the first 24 h of TSD and after that maintained its values without significant changes. DBP did not show any significant variations during TSD. In addition, there were no differences in function of gender for the TSD effect on the studied variables. All these statistically significant findings, however, seem to have no biological or clinical relevance. These aspects as well as the possible relationships between our results and activation or stress levels during TSD are discussed.
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Han, Lan, Zhaojie Ji, Weidong Chen, Dengke Yin, Fan Xu, Shanshan Li, Fangfang Chen, Guangyu Zhu, and Daiyin Peng. "Protective Effects of Tao-Hong-Si-Wu Decoction on Memory Impairment and Hippocampal Damage in Animal Model of Vascular Dementia." Evidence-Based Complementary and Alternative Medicine 2015 (2015): 1–12. http://dx.doi.org/10.1155/2015/195835.

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Tao-Hong-Si-Wu decoction (TSD) as a traditional chinese medicine (TCM) has been developed to treat thrombotic diseases for hundreds of years, and vascular dementia (VD) is a cognitive dysfunction syndrome caused by cerebral embolism. In this study, the protective effect of TSD on memory impairment and brain damage in rat model of VD induced by middle cerebral artery occlusion (MCAO) was investigated. The study showed that rats in MCAO treatment with TSD for 14 days significantly improved behavioral function, increased densities of neuron, and induced angiogenesis in the brain compared with model rats. TSD also adjusted the neurotransmitter levels, reduced the content of endothelin-1 (ET-1), and induced the activities of vascular endothelial growth factor (VEGF) in hippocampus. Moreover, the immunohistochemical staining and western blotting results also revealed that TSD decreased apoptosis via upregulated B-cell lymphoma-2 (Bcl-2)/Bcl-2 associated X protein (Bax) ratio. These results demonstrated TSD possesses neuroprotective and antidementia properties by preventing the loss of neural cells, adjusting brain neurotransmitter, promoting cerebral blood circulation, and decreasing apoptosis. These results suggested that TSD might be developed as an effective drug for the prevention of VD.
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Tang, Zhi, Ming Yin, Yuxing Guo, Wei Li, Fei Sun, Yonglin Guo, Zhenzhong Chen, and Biao Zhou. "Taohong Siwu Decoction Promotes Osteo-Angiogenesis in Fractures by Regulating the HIF-1α Signaling Pathway." Evidence-Based Complementary and Alternative Medicine 2022 (September 20, 2022): 1–10. http://dx.doi.org/10.1155/2022/6777447.

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Background. Vascular damage is a major consequence of bone fracture. Taohong Siwu decoction (TSD) can raise the expression of vascular endothelial growth factor (VEGF) in fracture healing. However, its molecular mechanism in promoting angiogenesis is still unknown. The aim of this study was to investigate the potential mechanisms of TSD in the regulation of osteo-angiogenesis in fracture healing. Methods. A rat tibial fracture model was established. After low- (4.5 g·kg−1), medium- (9 g·kg−1), and high-dose TSD (18 g·kg−1) and panax notoginsenoside (25 mg kg−1) treatment, hematoxylin-eosin staining was employed to visualize pathological changes in bone tissues. The levels of cytokines (interleukin (IL)-2, tumor necrosis factor-α (TNF-α), IL-6, and IL-1β), thromboxane B2 (TXB2), and 6 ketone prostaglandin F1α (6-Keto-PGF1α) were quantified by enzyme-linked immunosorbent assay (ELISA). Immunofluorescence was used to identify the rat aortic endothelial cells (RAECs). Control serum, 10% TSD-containing serum, and 10% TSD-containing serum combined with hypoxia-inducible factor-1α (HIF-1α) inhibitor were used to treat the RAECs and rat osteoblasts. Transwell migration assay was utilized to examine the migration of the RAECs. The Matrigel tubulogenesis assay was used for the assessment of angiogenesis. The expression of angiogenesis- (von Hippel-Lindau tumor suppressor (VHL), HIF-1α, VEGF, angiopoietin-2 (Ang-2), and pVHL) and osteogenesis-related (alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), and osteopontin-1 (OPN-1)) protein and gene was detected by western blot and quantitative real-time PCR (qRT-PCR). Results. Compared with the model group, TSD increased the trabecular bone areas, numbers, and thicknesses in fractured rats. In the plasma, the levels of cytokines and TXB2 in the middle- and high-dose TSD group were significantly lower than those in the model group ( P < 0.01 ). The 6-keto-PGF1α content was increased by middle- and high-dose TSD intervention ( P < 0.01 ). Compared to the control serum group, the angiogenesis and migration of the RAECs were enhanced in the TSD group ( P < 0.001 ). The expression of HIF-1α, VEGF, and Ang-2 in the TSD group upregulated significantly ( P < 0.001 ). VHL and pVHL were inhibited under TSD-containing serum treatment ( P < 0.001 ). ALP, Runx2, and OPN-1 were increased obviously in the TSD group ( P < 0.001 ). Nevertheless, the HIF-1α inhibitor reversed these changes ( P < 0.001 ). Conclusion. TSD promotes angiogenesis and osteogenesis by regulating the HIF-1α signaling pathway. Meanwhile, it can effectively reduce the risk of inflammation and improve blood circulation.
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Carter, Jason R., John J. Durocher, Robert A. Larson, Joseph P. DellaValla, and Huan Yang. "Sympathetic neural responses to 24-hour sleep deprivation in humans: sex differences." American Journal of Physiology-Heart and Circulatory Physiology 302, no. 10 (May 15, 2012): H1991—H1997. http://dx.doi.org/10.1152/ajpheart.01132.2011.

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Sleep deprivation has been linked to hypertension, and recent evidence suggests that associations between short sleep duration and hypertension are stronger in women. In the present study we hypothesized that 24 h of total sleep deprivation (TSD) would elicit an augmented pressor and sympathetic neural response in women compared with men. Resting heart rate (HR), blood pressure (BP), and muscle sympathetic nerve activity (MSNA) were measured in 30 healthy subjects (age, 22 ± 1; 15 men and 15 women). Relations between spontaneous fluctuations of diastolic arterial pressure and MSNA were used to assess sympathetic baroreflex function. Subjects were studied twice, once after normal sleep and once after TSD (randomized, crossover design). TSD elicited similar increases in systolic, diastolic, and mean BP in men and women (time, P < 0.05; time × sex, P > 0.05). TSD reduced MSNA in men (25 ± 2 to 16 ± 3 bursts/100 heart beats; P = 0.02), but not women. TSD did not alter spontaneous sympathetic or cardiovagal baroreflex sensitivities in either sex. However, TSD shifted the spontaneous sympathetic baroreflex operating point downward and rightward in men only. TSD reduced testosterone in men, and these changes were correlated to changes in resting MSNA ( r = 0.59; P = 0.04). Resting HR, respiratory rate, and estradiol were not altered by TSD in either sex. In conclusion, TSD-induced hypertension occurs in both sexes, but only men demonstrate altered resting MSNA. The sex differences in MSNA are associated with sex differences in sympathetic baroreflex function (i.e., operating point) and testosterone. These findings may help explain why associations between sleep deprivation and hypertension appear to be sex dependent.
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41

Silva, Denivaldo Pantoja da. "Ensino remoto emergencial em matemática e o Milieu didático-virtual: uma reflexão teórico-propositiva em contexto institucional e adverso." Amazônia: Revista de Educação em Ciências e Matemáticas 17, no. 39 (December 29, 2021): 288. http://dx.doi.org/10.18542/amazrecm.v17i39.11402.

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Este trabalho tem como objetivo promover uma reflexão teórico-propositiva sobre Ensino Remoto Emergencial (ERE) considerando alguns aspectos do ensino de Matemática e o ERE como instrumento didático-pedagógico crucial no desenvolvimento de atividades acadêmicas integrado em um sistema de Ensino Remoto Institucional (ERI), entendidos no sentido do Milieu didático proposto pela Teoria das Situações Didáticas (TSD) ressignificado pela Teoria Antropológica do Didático (TAD), no espaço universitário e, ao mesmo tempo, expor de modo propositivo a noção ampliada de Milieu Didático-Virtual (MD)V ressignificado em contexto adverso de pandemia/pós pandemia da Covid-19. Para isso, recorremos ao estudo bibliográfico-investigativo em documentos específicos, articulados com base na TSD e na TAD. Os resultados do estudo revelam que o modelo de ensino tradicionalmente desenvolvido nas instituições de ensino – básico e superior – se fragilizou diante do estado de pandemia, exigindo mudanças e reconstruções imediatas, entendendo-se que a padronização de métodos de ensino mediados por tecnologias digitais à distância requer estruturação consistente, bem como o modo de entender o ensino de Matemática em milieux remotos que se estabelecem em contexto pandêmico.
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42

Goel, Namni, Kathleen Rosendahl-Garcia, and Lauren Pasetes. "0207 Acute Total Sleep Deprivation Adversely Impacts Cardiovascular Measures across Long-Duration Intervals." SLEEP 46, Supplement_1 (May 1, 2023): A92. http://dx.doi.org/10.1093/sleep/zsad077.0207.

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Abstract Introduction For the first time, we comprehensively investigated the effects of repeated exposures to baseline (BL), total sleep deprivation (TSD), and recovery (REC) phases at 2, 4, and 8 months on cardiovascular (CV) measures. Methods We conducted a five-day experiment twice (at months 2 and 4) in a 4-month study (N=6 healthy adults; 3 females), and a similar five-day experiment three times (at months 2, 4, and 8) in an 8-month study (N=5 healthy adults; 2 females). During these repeated experiments, CV measures were collected via echocardiography or blood pressure monitor [systolic and diastolic blood pressure (SBP and DBP)] at three assessment time points: 1) after two baseline 8h time in bed (TIB) nights (BL); 2) after a night of total sleep deprivation (TSD); and 3) after two recovery nights of 8-10h TIB (REC). CV measures were also collected once pre and post study. Seated stroke volume (SV), cardiac index (CI), left ventricular ejection time (LVET), SBP and DBP, systemic vascular resistance index (SVRI), and mean arterial pressure (MAP) were collected. Data did not significantly differ between the two studies and therefore were pooled together for analysis (N=11). Repeated measures ANOVA and post-hoc comparisons corrected for multiple testing examined CV measures across all time points. Results SV, CI, SVRI, LVET, and SBP, but not DBP or MAP, showed significant changes across time. SV increased with TSD compared to pre-study, BL, and post-study at month 2. CI increased with TSD compared to pre-study, BL, REC, and post-study at month 2. SVRI decreased with TSD compared to pre-study, BL, and REC at month 2 and LVET and SBP increased with TSD compared to BL at month 2. In the 8-month sample subset, SBP increased with TSD compared to BL at month 8. Conclusion TSD increased SV, CI, LVET, and SBP, and decreased SVRI, compared to BL at month 2. Notably, TSD also increased SBP compared to BL at month 8, indicating a sustained adverse effect after long-duration repeated exposure to TSD. Overall, SV, CI, SVRI, LVET, and SBP are reliable biomarkers for assessing the harmful long-term cardiovascular effects of TSD. Support (if any) NASA grants NNX14AN49G and 80NSSC20K0243 (NG)
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43

Isaksson, A., B. Hultberg, P. Masson, E. Landels, and A. Fensom. "Enzyme immunoassay of beta-hexosaminidase A and B in serum: carrier detection of GM2-gangliosidoses, and equivalence of enzyme activity and enzyme protein reactivity." Clinical Chemistry 39, no. 7 (July 1, 1993): 1412–15. http://dx.doi.org/10.1093/clinchem/39.7.1412.

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Abstract beta-Hexosaminidase (Hex; EC 3.2.1.52) isoenzymes A and B were analyzed in sera from a control group of 22 apparently healthy subjects, 13 obligate carriers of Tay-Sachs disease (TSD), 10 obligate carriers of Sandhoff disease (SHD), and 4 affected TSD patients by enzyme immunoassay methods based on enzyme activity. No Hex A activity was detected in the sera of patients with TSD. The activities of Hex A in the obligate carriers of TSD and SHD tended to be lower (nonsignificantly) than in the control group. Hex B activities tended to be higher in TSD patients as well as in carriers of TSD, although the mean activities did not significantly differ from the corresponding mean for the control group. However, Hex B activities were decreased in the carriers of SHD in comparison with the other groups. Sera from 900 postmenopausal women, all of age 55 years, were also analyzed for Hex isoenzymes; the results indicated a carrier frequency of about 1 in 200 for both TSD and SHD. We also compared the enzyme immunoassay method based on enzyme activity with one based on the antigenic (enzyme protein) reactivity alone. Because both methods yielded similar information, we conclude that no significant amounts of inactive enzyme protein are present in the circulation.
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44

Arjadi, Fitranto, Wahyudin Wahyudin, and Joko Setyono. "Differences in body weight post-induction sleep deprivation and sleep recovery in white male rats (Rattus norvegicus)." AcTion: Aceh Nutrition Journal 8, no. 2 (June 4, 2023): 219. http://dx.doi.org/10.30867/action.v8i2.930.

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Sleep Deprivation (SD) reduced leptin levels, increased ghrelin levels, and it caused were multifactorial, so research was conducted on experimental animals to prove whether SD was the single factor causing changes in body weight (BW). The study's objectives were to know the difference in BW after induction of paradoxical and total SD and to observe the improvement in sleep recovery (SR). This study was true experimental with posttest only, and a control group design used 25 male albino rats randomly shared into five groups; control, PSD, TSD, PSD+SR, dan TSD+SR on August – September 2021. The weight is measured by OHAUS® balance. Statistical analysis used by One-way ANOVA and paired t-test denoted no significant difference after SD (p=0,277) and SR (p=0,297), a significant difference in the TSD+SR and TSD between before (p=0,014), after SD (p=0,008), and after SR (p=0,034). Sleep deprivation increases BW through raised ghrelin, and SR reverses the effects by increasing the antioxidant. Results must be confirmed by measuring ghrelin levels and leptin orexin type 1 and 2 receptors. In conclusion, that was a significant difference in the TSD+SR and TSD between pre and post-sleep deprivation and the TSD+SR between pre and post-SR.
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45

Xiong, Liang-Bin, Jia-Lin Li, Bo Yang, and Ying Yu. "Ti3+in the Surface of Titanium Dioxide: Generation, Properties and Photocatalytic Application." Journal of Nanomaterials 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/831524.

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Titanium dioxide (TiO2) is the most investigated crystalline oxide in the surface science of metal oxides. Its physical and chemical properties are dominantly determined by its surface condition. Ti3+surface defect (TSD) is one of the most important surface defects in TiO2. According to publications by other groups and the studies carried out in our laboratory, the formation mechanism of TSD is proposed. The generation, properties, and photocatalytic application of TSD are overviewed; the recent exploration of TSD is summarized, analyzed, and evaluated as well in this paper.
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46

Roy, Anuja, Zili Zhang, Aparna (Dey) Ghosh, and Biswajit Basu. "On the nonlinear performance of a tuned sloshing damper under small amplitude excitation." Journal of Vibration and Control 25, no. 21-22 (July 29, 2019): 2695–705. http://dx.doi.org/10.1177/1077546319867232.

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This paper explores the potential of a tuned sloshing damper (TSD) in the control of small amplitude vibrations, which is often important from serviceability considerations, through the use of a relatively small mass ratio of the damper liquid. To investigate the nonlinear behavior of the TSD, real-time hybrid testing is conducted in which a single rectangular tank containing water constitutes the prototype TSD. The structure is modeled as a multi-degree-of-freedom system. Two different base input motions, namely harmonic and synthetically generated broad-banded input, are considered. The sensitivity of the TSD performance to tuning ratio vis-à-vis low mass ratio is studied. The experimental results are compared with those obtained from a numerical study carried out using the shallow water wave theory-based nonlinear, semi-empirical model, for the simulation of the sloshing motion of the TSD liquid (water). Results indicate that in the tuned condition, even with a low mass ratio, the TSD is highly effective in the suppression of the small amplitude vibrations, which is underestimated by the simulation model.
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47

Koster, Gaia T., T. Truc My Nguyen, Adrien E. D. Groot, Jonathan M. Coutinho, Jan Bosch, Heleen M. den Hertog, Marianne A. A. van Walderveen, et al. "A Reduction in Time with Electronic Monitoring In Stroke (ARTEMIS): study protocol for a randomised multicentre trial." BMJ Open 8, no. 6 (June 2018): e020844. http://dx.doi.org/10.1136/bmjopen-2017-020844.

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IntroductionTime is the most crucial factor limiting efficacy of intravenous thrombolysis (IVT) and intra-arterial thrombectomy (IAT). The delay between alarming the Emergency Medical Services (EMS) dispatch office and IVT/IAT initiation, that is, the‘total system delay’(TSD), depends on logistics and team effort. A promising method to reduce TSD is real-time audio-visual feedback to caregivers involved. With ‘A Reduction in Time with Electronic Monitoring in Stroke’ (ARTEMIS), we aim to investigate the effect of real-time audio-visual feedback on actual TSD to IVT/IAT to caregivers.Methods and analysisARTEMIS is a multiregional, multicentre, randomised open end-point trial including patients ≥18 years considered IVT/IAT-eligible by the EMS dispatch office or on-site EMS personnel. Patients are electronically tracked and randomised for real-time audio-visual feedback on TSD to caregivers via premounted handhelds and tablets throughout the TSD trajectory. Primary outcome is TSD to IVT/IAT. Secondary outcomes comprise proportion of IVT/IAT-treated patients, symptomatic intracerebral haemorrhage, IVT/IAT-treated stroke mimics, clinical outcome after three months and cost-effectiveness. Separate analyses for IAT-patients with or without prior IVT, within or out of office hours and EMS region will be performed. With 75 IAT-patients and 225 IVT-patients in each arm, we will be able to demonstrate a 20 min difference in TSD to IAT and a 10 min difference in TSD to IVT (p=0.05 and power=0.8).Ethics and disseminationStudy findings will be disseminated through peer-reviewed journals and (inter)national conference presentations.Trial registration numberNCT02808806
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48

Zhaoxu Wang, Huachun Zhou, and Wei Quan. "Tracing Link Flooding Attacks in MobilityFirst Networks." Research Briefs on Information and Communication Technology Evolution 4 (October 15, 2018): 114–24. http://dx.doi.org/10.56801/rebicte.v4i.72.

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Current link flooding attack (LFA) defense strategies highly rely on static network topology and precollectedtraceroute record in current Internet, which are not fit for the MobilityFirst networks. Wepropose the traffic scanning defense (TSD) mechanism against LFA in MobilityFirst. TSD is cooperative,fast and stateless, and also scalable to implement in MFTP for MobilityFirst. Preliminary testsshow promising efficiency of TSD.
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Shao, Yongcong, Jianlin Qi, Ming Fan, Enmao Ye, Bo Wen, Guohua Bi, Zheng Yang, and Danmin Miao. "Compensatory Neural Responses After 36 Hours of Total Sleep Deprivation and its Relationship with Executive Control Function." Social Behavior and Personality: an international journal 37, no. 9 (October 1, 2009): 1239–49. http://dx.doi.org/10.2224/sbp.2009.37.9.1239.

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The neurobiological mechanisms of Total Sleep Deprivation (TSD) - induced changes in executive control function were investigated. Fourteen participants were measured by functional magnetic resonance imaging (fMRI) with the visual Go/No-go task after normal sleep and following 36 hours of TSD. The TSD-induced positive and negative blood oxygenation level-dependent (BOLD) signals compared with that after a normal night's sleep (NORM). The areas activated with positive BOLD signals include the superior prefrontal cortex and inferior prefrontal cortex, with negative BOLD signals in the anterior cingulated cortex (ACC) and right lingual gyrus. Increased activation may be related to the compensatory response since more attention resources are needed to perform the Go/No-go task after 36 hours of TSD and the decreased activation in the ACC may reflect the impact of executive control function by the TSD.
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Li, Shuran, Zhiwang Xu, Laigao Luo, Jun Ping, Huabin Zhou, Lei Xie, and Yongpu Zhang. "Latitudinal Variation in the Pattern of Temperature-Dependent Sex Determination in the Japanese Gecko, Gekko japonicus." Animals 12, no. 8 (April 7, 2022): 942. http://dx.doi.org/10.3390/ani12080942.

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Identifying latitudinal variation in the pattern of temperature-dependent sex determination (TSD) may provide insight into the evolution of sex determining system in vertebrates, but such studies remain limited. Here, we quantified TSD patterns of three geographically separated populations of the Japanese gecko (Gekko japonicus) along the latitudinal cline of China. We incubated gecko eggs from the three populations at constant temperatures of 24, 26, 28, 30, and 32 °C to quantify the TSD pattern. Our study demonstrated that G. japonicus exhibited a FMF pattern of TSD, with the low and high incubation temperatures yielding significantly female-biased hatchlings, and the medium temperatures producing male-biased hatchlings. More interestingly, we found latitudinal variations in the TSD pattern in terms of pivotal temperatures (Tpivs), transitional range of temperatures (TRT), and the sex ratios at the medium temperatures. The Tpivs for the low-latitude population were lower than those for the two high-latitude populations. The low-latitude population has a narrower FM TRT, but a wider MF TRT. The sex ratio is almost 50:50 for the low-latitude population when eggs were incubated from 26 to 30 °C. Conversely, the sex ratio is male-biased for the two high-latitude populations at 28 or 30 °C. Therefore, G. japonicus may provide an interesting system to explore the evolution of TSD in reptiles given the diversity of TSD patterns among populations.
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