In this work, a high thermoelectric figure of merit, zT of 1.9 at 740 K is achieved in Ge
Bi
Te crystals through the concurrent of Seebeck coefficient enhancement and thermal conductivity reduction ...with Bi dopants. The substitution of Bi for Ge not only compensates the superfluous hole carriers in pristine GeTe but also shifts the Fermi level (E
) to an eligible region. Experimentally, with moderate 6-10% Bi dopants, the carrier concentration is drastically decreased from 8.7 × 10
cm
to 3-5 × 10
cm
and the Seebeck coefficient is boosted three times to 75 μVK
. In the meantime, based on the density functional theory (DFT) calculation, the Fermi level E
starts to intersect with the pudding mold band at L point, where the band effective mass is enhanced. The enhanced Seebeck coefficient effectively compensates the decrease of electrical conductivity and thus successfully maintain the power factor as large as or even superior than that of the pristine GeTe. In addition, the Bi doping significantly reduces both thermal conductivities of carriers and lattices to an extremely low limit of 1.57 W m
K
at 740 K with 10% Bi dopants, which is an about 63% reduction as compared with that of pristine GeTe. The elevated figure of merit observed in Ge
Bi
Te specimens is therefore realized by synergistically optimizing the power factor and downgrading the thermal conductivity of alloying effect and lattice anharmonicity caused by Bi doping.
To investigate the underlying mechanisms of T2D pathogenesis, we looked for diabetes susceptibility genes that increase the risk of type 2 diabetes (T2D) in a Han Chinese population. A two-stage ...genome-wide association (GWA) study was conducted, in which 995 patients and 894 controls were genotyped using the Illumina HumanHap550-Duo BeadChip for the first genome scan stage. This was further replicated in 1,803 patients and 1,473 controls in stage 2. We found two loci not previously associated with diabetes susceptibility in and around the genes protein tyrosine phosphatase receptor type D (PTPRD) (P = 8.54x10(-10); odds ratio OR = 1.57; 95% confidence interval CI = 1.36-1.82), and serine racemase (SRR) (P = 3.06x10(-9); OR = 1.28; 95% CI = 1.18-1.39). We also confirmed that variants in KCNQ1 were associated with T2D risk, with the strongest signal at rs2237895 (P = 9.65x10(-10); OR = 1.29, 95% CI = 1.19-1.40). By identifying two novel genetic susceptibility loci in a Han Chinese population and confirming the involvement of KCNQ1, which was previously reported to be associated with T2D in Japanese and European descent populations, our results may lead to a better understanding of differences in the molecular pathogenesis of T2D among various populations.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A record high zT of 2.2 at 740 K is reported in Ge0.92Sb0.08Te single crystals, with an optimal hole carrier concentration ≈4 × 1020 cm−3 that simultaneously maximizes the power factor (PF) ≈56 ...µW cm−1 K−2 and minimizes the thermal conductivity ≈1.9 Wm−1 K−1. In addition to the presence of herringbone domains and stacking faults, the Ge0.92Sb0.08Te exhibits significant modification to phonon dispersion with an extra phonon excitation around ≈5–6 meV at Γ point of the Brillouin zone as confirmed through inelastic neutron scattering (INS) measurements. Density functional theory (DFT) confirmed this phonon excitation, and predicted another higher energy phonon excitation ≈12–13 meV at W point. These phonon excitations collectively increase the number of phonon decay channels leading to softening of phonon frequencies such that a three‐phonon process is dominant in Ge0.92Sb0.08Te, in contrast to a dominant four‐phonon process in pristine GeTe, highlighting the importance of phonon engineering approaches to improving thermoelectric (TE) performance.
The origin of high zT ≈ 2.2 at 740 K of Ge0.92Sb0.08Te is uncovered via DFT and inelastic neutron scattering measurements that reveal the presence of a new phonon band at a transfer energy E ≈5–6 meV, highlighting the importance of phonon engineering approaches to improving thermoelectricperformance.
Thyroid function may alter carbohydrate metabolism via influence of insulin, which may in terms of derangement of thyroid function and insulin function result in the development of type 2 diabetes ...mellitus (T2D). We investigated the association of thyroid disorders with T2D by a cohort study of the Taiwan nationwide health insurance database.A sub-dataset of the National Health Insurance Research Database (NHIRD) was used in this study. The thyroid disease (both hyper- and hypo-thyroidism) group was chosen from patients older than 18 years and newly diagnosed between 2000 and 2012. The control group consisted of randomly selected patients who never been diagnosed with thyroid disease and 4-fold size frequency matched with the thyroid disease group. The event of this cohort was T2D (ICD-9-CM 250.x1, 250.x2). Primary analysis was performed by comparing the thyroid disease group to the control group and the second analysis was performed by comparing the hyperthyroidism subgroup, hypothyroidism subgroup, and control group.The occurrence of T2D in the thyroid disease group was higher than the control group with hazard ratio (HR) of 1.23 95% confidence interval (CI) = 1.16-1.31. Both hyperthyroidism and hypothyroidism were significantly higher than control. Significantly higher HR was also seen in female patients, age category of 18 to 39-year-old (y/o) and 40 to 64 y/o subgroups. Higher occurrence of T2D was also seen in thyroid disease patients without comorbidity than in the control group with HR of 1.47 (95% CI = 1.34-1.60). The highest HR was found in the half-year follow-up.There was a relatively high risk of T2D development in patients with thyroid dysfunctions, especially in the period of 0.5 to 1 year after presentation of thyroid dysfunctions. The results suggest performing blood sugar tests in patients with thyroid diseases for early detection and treatment of T2D.
Glycated hemoglobin A1c (HbA1c) variation or blood pressure (BP) variation was known to be an independent predictor of all-cause mortality in patients with type 2 diabetes mellitus (T2DM). This study ...aimed to investigate the combined effect of HbA1c and systolic blood pressure (SBP) variation on all-cause mortality and if there was a gender difference in patients with T2DM.
Patients with T2DM who had at least three HbA1c, SBP measurements within 12–24 months during 2001–2007 were included. Coefficient of variation (CV) was used to evaluate variation. The 75th percentile of HbA1c-CV and SBP-CV were set as a cutoff to define high and low variation. Hazard ratios (HRs) and 95% confidence intervals were estimated using Cox proportional hazard models.
A total of 2744 patients were included, of whom 769 died during the 11.7 observation years. The associated risk of all-cause mortality was 1.22 1.01- 1.48, P = 0.044, for low HbA1c-CV & high SBP-CV; 1.28 1.04–1.57, P = 0.020, for high HbA1c-CV & low SBP-CV; and 1.68 1.31–2.17, P < 0.001, for high HbA1c-CV & high SBP-CV. The associated risk remained unchanged in either males or females older than 50 years old, although there is only numerically higher for high HbA1c-CV & low SBP-CV in females older than 50 years old.
Both HbA1c and SBP variation were significant predictors of all-cause mortality in patients with T2DM. The combined effect was higher than either alone and no gender difference in patients older than 50 years old.
•Achieving BP & HbA1c target is important for lowering cardiovascular events in T2DM.•Variation in BP or HbA1c is associated with higher risk of all-caused morality.•The combined effect of SBP & HbA1c variation is higher than either alone and there is no gender difference.•Minimizing variations in SBP and HbA1c were important in our clinical practice.
This study evaluates whether B7 molecules (CD80 and CD86) could be used as genetic markers for the development of Graves' ophthalmopathy (GO).
Cross-sectional study.
We included 471 patients with ...Graves' disease (GD; 200 patients with GO and 271 patients without GO) in a Chinese population in Taiwan.
An endocrinologist with substantial experience in thyroid diseases identified GO. Blood samples were taken for DNA extraction from GD subjects. The gene polymorphism of CD80 and CD86 was genotyped by polymerase chain reaction in each patient.
Genotypes of CD80 and CD86 polymorphism.
We found that the frequency of C allele at position rs_9831894 of the CD86 gene is different in patients with GD (with and without GO; chi-square test, P = 0.0017). In addition, the multifactor dimensionality reduction method was used to identify the best gene-gene interaction to predict the risk of GO. We identified an interaction between CD80_rs9289131 and CD86_rs9872483 (sign test, P = 0.0010). Moreover, the G-A haplotype was shown to have a protective effect in the development of ophthalmopathy among patients with GD (odds ratio, 0.63; 95% confidence interval, 0.44-0.90). Moreover, among patients with GO, the patients carrying the G-A haplotype had a lower level of free thyroxine T(4) than those not carrying the G-A haplotype (P = 0.0001).
These results suggest that the polymorphisms of the CD86 gene may be used as genetic markers for making the diagnosis and prognosis of GO. Therefore, GO could be a disease with complex genetic factors, resulting from the existing gene-gene interaction found in the present study.
Single-crystalline SnSe has attracted much attention because of its record high figure-of-merit ZT ≈ 2.6; however, this high ZT has been associated with the low mass density of samples which leaves ...the intrinsic ZT of fully dense pristine SnSe in question. To this end, we prepared high-quality fully dense SnSe single crystals and performed detailed structural, electrical, and thermal transport measurements over a wide temperature range along the major crystallographic directions. Our single crystals were fully dense and of high purity as confirmed via high statistics 119Sn Mössbauer spectroscopy that revealed <0.35 at. % Sn(IV) in pristine SnSe. The temperature-dependent heat capacity (C p) provided evidence for the displacive second-order phase transition from Pnma to Cmcm phase at T c ≈ 800 K and a small but finite Sommerfeld coefficient γ0 which implied the presence of a finite Fermi surface. Interestingly, despite its strongly temperature-dependent band gap inferred from density functional theory calculations, SnSe behaves like a low-carrier-concentration multiband metal below 600 K, above which it exhibits a semiconducting behavior. Notably, our high-quality single-crystalline SnSe exhibits a thermoelectric figure-of-merit ZT ∼1.0, ∼0.8, and ∼0.25 at 850 K along the b, c, and a directions, respectively.
Background:
To date, no comprehensive epidemiological study exists on pyogenic liver abscess (PLA) risk in patients with newly diagnosed type 2 diabetes mellitus (T2DM) worldwide.
Methods:
We ...conducted a retrospective cohort study by using data from Taiwan National Health Insurance Research Database (NHIRD) to examine the association between newly diagnosed T2DM and PLA. The T2DM cohort included patients newly diagnosed as having T2DM (ICD-9-CM:250) from 2000 to 2009, with follow-up until December 31, 2011. The comparison cohort was then recruited through 1:4 random frequency matching with the T2DM cohort. Finally, the adjusted hazard ratios for PLA were compared between the T2DM and comparison cohorts, which included 44,728 patients with T2DM and 178,912 patients without DM respectively.
Results:
In T2DM cohort, 166 patients were diagnosed as having PLA (incidence rate = 5.87 per 10,000 person-years) and in comparison cohort, 238 patients were diagnosed as having PLA (incidence rate = 2.06 per 10,000 person-years). The T2DM cohort exhibited higher PLA risk than did the comparison cohort (hazard ratio = 2.83, 95% confidence interval = 2.32–3.46). Furthermore, the adjusted hazard ratio for PLA risk in T2DM cohort was the highest in those who were younger, man and with duration of DM <2 years. In the T2DM cohort, the most common PLA causative agent was Klebsiella pneumonia (KP). In addition, PLA risk was high in T2DM patients with gallstone and cholecystitis. Compared with comparison cohort, patients with T2DM prescribed acarbose has a lower PLA risk, however glyburide significantly increased PLA risk in T2DM cohort.
Conclusion:
In patients with newly diagnosed T2DM, PLA risk was high and acarbose might reduce PLA risk.
Objective. Autologous fat injection laryngoplasty is ineffective for some patients with iatrogenic vocal fold paralysis, and additional laryngeal framework surgery is often required. An acoustically ...measurable outcome predictor for lipoinjection laryngoplasty would assist phonosurgeons in formulating treatment strategies. Methods. Seventeen thyroid surgery patients with unilateral vocal fold paralysis participated in this study. All subjects underwent lipoinjection laryngoplasty to treat postsurgery vocal hoarseness. After treatment, patients were assigned to success and failure groups on the basis of voice improvement. Linear prediction analysis was used to construct a new voice quality indicator, the number of irregular peaks (NIrrP). It compared with the measures used in the Multi-Dimensional Voice Program (MDVP), such as jitter (frequency perturbation) and shimmer (perturbation of amplitude). Results. By comparing the i vowel produced by patients before the lipoinjection laryngoplasty (AUC = 0.98, 95% CI = 0.78–0.99), NIrrP was shown to be a more accurate predictor of long-term surgical outcomes than jitter (AUC = 0.73, 95% CI = 0.47–0.91) and shimmer (AUC = 0.63, 95% CI = 0.37–0.85), as identified by the receiver operating characteristic curve. Conclusions. NIrrP measured using the LP model could be a more accurate outcome predictor than the parameters used in the MDVP.
Objectives. In traditional Chinese medicine, Yu-Zhi (YZ, indicating stasis and stagnation) constitution describes a body that tends to express abnormal circulatory conditions. This study identified ...the linkage between YZ constitution and peripheral arterial disease (PAD) in patients with type 2 diabetes. Methods. Patients over 20 years of age who had had type 2 diabetes for 5 years or longer were recruited. PAD was diagnosed if the ankle-brachial index score was ≤0.9 in either leg. Level of YZ constitution was accessed by an YZ Constitution Questionnaire. Results. A total of 712 patients (354 men and 358 women) with a mean age of 61.5 ± 10.6 years and diabetes duration of 13.1 ± 6.7 years were recruited. The prevalence of PAD among our patients was 7.2%. Multivariate logistic regression revealed significant correlations between PAD and, respectively, YZ score, age, diabetes duration, current smoking, and hs-CRP. Conclusion. In addition to traditional risk factors, YZ constitution was statistically associated with PAD in patients with type 2 diabetes. This result invites further research into the effectiveness of traditional Chinese medicine to treat YZ constitution.
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