Highly Reliable Magnetic Memory-Based Physical Unclonable Functions.

Magnetic random-access memory (MRAM), which stores information through control of the magnetization direction, offers promising features as a viable nonvolatile memory alternative, including high endurance and successful large-scale commercialization. Recently, MRAM applications have extended beyond traditional memories, finding utility in emerging computing architectures such as in-memory computing and probabilistic bits. In this work, we report highly reliable MRAM-based security devices, known as physical unclonable functions (PUFs), achieved by exploiting nanoscale perpendicular magnetic tunnel junctions (MTJs). By intentionally randomizing the magnetization direction of the antiferromagnetically coupled reference layer of the MTJs, we successfully create an MRAM-PUF. The proposed PUF shows ideal uniformity and uniqueness and, in particular, maintains performance over a wide temperature range from -40 to +150 °C. Moreover, rigorous testing with more than 1584 challenge-response pairs of 64 bits each confirms resilience against machine learning attacks. These results, combined with the merits of commercialized MRAM technology, would facilitate the implementation of MRAM-PUFs.

Craniofacial Phenotype in Obstructive Sleep Apnea and Its Impact on Positive Airway Pressure (PAP) Adherence.

Positive airway pressure (PAP) is an important treatment tool for patients with moderate and severe obstructive sleep apnea (OSA), and adherence to PAP significantly affects treatment outcomes. Disease severity, adverse effects, and psychosocial factors are known to predict medication adherence. Cephalometric parameters have been reported to positively correlate with upper airway collapse. However, research on the correlation between these cephalometric parameters and PAP adherence remains insufficient. This study aimed to identify this relationship. This study included 185 patients with OSA who were prescribed PAP. Polysomnography (PSG) was performed to diagnose OSA, and paranasal sinus computed tomography (PNS CT) was performed to check for comorbidities of the upper airway. In addition, cephalometric parameters such as the hyoid-posterior nasal spine (H-PNS), posterior nasal spine-mandibular plane (PNS-MP), and hyoid-mandibular plane (H-MP) were measured in the midsagittal and axial CT views. Adherence was evaluated 3-12 months after the PAP prescription. A total of 136 patients were PAP-adherent, and 49 were nonadherent. There were more males in the adherent group and a higher average height in the adherent group. The PSG results showed that the apnea-hypopnea index (AHI), respiratory disturbance index (RDI), oxygen desaturation index (ODI), arousal index (AI), rapid eye movement (REM) AHI, and supine AHI were significantly higher, and the lowest oxygen saturation was lower in the adherent group. In the analysis of covariance (ANCOVA) model adjusted for sex and height, among the cephalometric parameters, H-MP was significantly longer in the adherent group (p = 0.027), and H-PNS showed a longer tendency (p = 0.074). In the logistic regression analysis model, the odds ratio (OR) and 95% confidence intervals (95% CI) of adherence and severe OSA in the third tertile compared to the first tertile of H-MP were 2.93 (1.25-6.86) and 4.00 (1.87-8.56). In the case of H-PNS, they were 2.58 (1.14-5.81) and 4.86 (2.24-10.54), respectively. This study concluded that an inferiorly placed hyoid bone in adult patients is associated with PAP adherence and disease severity.

Effect of Intermittent Hypoxia on Metabolic Syndrome and Insulin Resistance in the General Male Population.

Background and objectives: Obstructive sleep apnea (OSA) is closely associated with insulin resistance (IR) and is an independent risk factor for incident type 2 diabetes mellitus (T2DM). Most studies evaluate the correlation between OSA and IR in only obese or T2DM patients. Therefore, we tried to investigate the effect of OSA on metabolic syndrome and IR in the general healthy male population. Materials and Methods: 184 subjects who visited a preventive health examination program were recruited for this study. All subjects received overnight polysomnography by a portable device (Watch-PAT 200). We examined several metabolic parameters and a homeostasis model of assessment for insulin resistance index (HOMA-IR). The subjects were divided into three groups by AHI (Apnea-hyponea index): normal group (AHI < 5), mild OSA group (5 ≤ AHI < 15), and moderate-severe OSA group (AHI ≥ 15). They were also divided into two groups according to minimum oxygen saturation: low group, Min-SpO2 < 88%; and high group, Min-SpO2 ≥ 88%. Results: Parameters of metabolic syndrome, including waist circumference, systolic and diastolic blood pressure, triglyceride, and high-density lipoprotein cholesterol showed significant differences among the AHI groups. Furthermore, HOMA-IR showed significant differences among the AHI groups. Those parameters, including metabolic syndrome and HOMA-IR, also showed differences between Min-SpO2 groups. Conclusions: In summary, this study helps confirm that AHI is associated with HOMA-IR in the general male population. Furthermore, the severity of AHI correlated with the parameters of metabolic syndrome. Therefore, AHI might be an indicator for evaluating both T2DM and metabolic syndrome, even in the general male population.

Benign paroxysmal positional vertigo secondary to inner ear disease.

OBJECTIVES: To contrast clinical characteristics of secondary benign paroxysmal positional vertigo (s-BPPV) with idiopathic BPPV (i-BPPV). STUDY DESIGN: Case series with chart review. SETTING: University hospital. SUBJECTS AND METHODS: A total of 718 patients whose medical records were reviewed had BPPV. Sixty-nine patients had existing inner ear diseases and thus were considered to have s-BPPV. We reviewed demographics, concurrent causative disorders, involved area, and response to particle repositioning maneuvers for these s-BPPV patients in comparison with i-BPPV subjects. RESULTS: Female subjects with i-BPPV outnumbered male subjects by a ratio of 1.9:1, but there was no significant sex difference for s-BPPV patients. The diseases associated with s-BPPV were idiopathic sudden sensory hearing loss (ISSHL, 50.7%), Ménière's disease (MD, 28.9%) and unilateral vestibulopathy such as acute vestibular neuronitis and herpes zoster oticus (20.2%). The posterior canal was most commonly involved in both i-BPPV and s-BPPV. The horizontal canal was the second most common, followed by multi-canal involvement. However, MD-associated BPPV most commonly involved the lateral canal. The mean durations of treatment for i-BPPV and s-BPPV were 2.28 and 4.87 days, respectively. The mean duration of treatment was 6.28 days for ISSHL with BPPV, 5.07 days for BPPV with unilateral vestibulopathy, and 2.28 days for BPPV with MD. CONCLUSION: The mean duration of treatment for BPPV with ISSHL or unilateral vestibulopathy was longer than for other groups. The different pathophysiologies of s-BPPV associated with different inner ear diseases may explain its diverse clinical features and courses.

Sclerotherapy of branchial cleft cysts using OK-432.

OBJECTIVES: OK-432 has been widely used to treat lymphangioma and ranula; however, there are few studies for its use in treatment of branchial cleft cyst (BCC). We conducted this study to evaluate the effectiveness of sclerotherapy using OK-432 in treatment of BCC. STUDY DESIGN AND SETTING: Case series with planned data collection. SUBJECTS AND METHODS: From 2004 to 2007, we treated 23 patients with BCC using OK-432 sclerotherapy. Of these 23 patients, 18 had unilocular cysts and five had multilocular cysts. The sizes of the BCCs were measured and compared before and after treatment. RESULTS: Of the 23 cases, 14 (60.8%) showed complete regression; all of these were unilocular cysts. Of the remaining individuals with unilocular cysts, only one patient failed to show any response. This individual subsequently underwent surgical excision. A total of five patients with multilocular cysts showed no or partial response and subsequently underwent surgical excision. Minor adverse effects including fever and local pain were reported by 13 (56.5%) patients. CONCLUSION: These results suggest that sclerotherapy using OK-432 is an effective and safe treatment modality for BCC, especially for unilocular cysts. Sclerosing of unilocular BCC with OK-432 should therefore be considered before surgical excision.

Vocal analysis related to changes in frequency of pure tone auditory feedback.

PURPOSE: Many studies have shown that subjects show a change of vocal fundamental frequency (F0) when phonating subjects hear their vocal pitch feedback shifted upward or downward. This study was performed to demonstrate whether vocal parameters [F0, intensity, jitter, shimmer, and noise to harmonic ratio (NHR)] in normal males respond to changes in frequency of pure tone masking. MATERIALS AND METHODS: Twenty healthy male subjects participated in this study. Subjects vocalized /a/ vowel sounds while listening to a pitch- shift pure tone through headphones (upward pitch-shift in succession: 1 kHz to 2 kHz and 1 kHz to 4 kHz at 50 dB or 80 dB, respectively, downward pitch-shift in succession: 1 kHz to 250 Hz and 1 kH to 500 Hz at 50 dB or 80 dB, respectively). RESULTS: Vocal intensity, F0, was increased, whereas jitter was decreased as the pitch of pure tone was shifted upward. However, there was no correlation between shimmer and NHR with pitch-shift feedback for pure tones. Unlike vocal pitch- shift feedback in other studies, upward pitch-shift feedback of pure tones caused the vocal F0 and intensity to change in the same direction as pitch-shift. CONCLUSION: The results of this study demonstrated that auditory kinesthetic feedback is affected by pitch-shift in pure tone.

Enhanced efficacy of DNA vaccination against Her-2/neu tumor antigen by genetic adjuvants.

Certain types of malignant tumors overexpress Her-2/neu, a transmembrane glycoprotein of the class I receptor tyrosine kinase erbB family. To develop an effective Her-2/neu vaccine for selective immunotherapy of these malignancies, we prepared Her-2/neu DNA plasmid encoding the transmembrane and extracellular domain (pHM) and tested the ability of this construct to induce antitumor immunity in animal models. In addition, we investigated the effects of cytokine used as a genetic adjuvant. Modulation by factors that affect T-cell function or hematopoiesis, including interleukin-12, interleukin-15, interleukin-18, interleukin-23, Eta-1, Flt3L and GM-CSF, was studied in the forms of monocistronic and bicistronic plasmid. Our results demonstrated that vaccination of pHM could induce successful antitumor immunity against Her-2/neu-expressing murine tumor cells in BALB/c mice. We also showed that the antitumor activity of pHM was augmented by coadministration and coexpression of different cytokines. Despite the similar levels of gene expression, the antitumor effects of bicistronic plasmids coexpressing Her-2/neu antigen and cytokine were improved in comparison with coadministration of separate monocistronic plasmid. In particular, coexpression of interleukin-18 or GM-CSF with Her-2/neu increased antitumor activity in both preventive and therapeutic experiments. These findings can help in the decision concerning which of the various cytokine adjuvants should be used for the development of a Her-2/neu DNA vaccine. In addition, our results from a large panel of cytokine adjuvants in the various tumor models may provide an insight into the important immune components of antitumor immunity.