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The beginning of human immunodeficiency virus (HIV) infection treatment depends on various factors, which are significantly correlated with the initial CD4 cell number. However, a covariate correlation between these factors may not reflect the correct outcome variable. Thus, we evaluated the effects of a combination of fixed factors (reduced dimensions), which determine when to start treatment for the first time, on short-term outcome, long-term outcome, and survival, considering correlations between factors. Multiple correspondence analysis was performed on variables obtained from 925 patients who participated in a Korean HIV/acquired immunodeficiency syndrome cohort study (2006–2017). Five reduced dimension groups were derived according to clinical data, viral load, CD4 cell count at diagnosis, initial antiretroviral therapy, and others. The dimension group with high initial viral loads (55,000 copies/mL) and low CD4 cell counts (3) should start treatment promptly after diagnosis. Groups with high initial CD4 cell counts (> 350 cells/mm3) that did not require immediate treatment according to previous guidelines had a higher failure rate for long-term relative CD4 recovery. Our results highlight the importance of early diagnosis and treatment to positively influence long-term disease outcomes, even if the initial immune status is poor, given the patient’s combination of early diagnostic symptoms.

Layered metal chalcogenides with highly promising thermoelectric properties have attracted attention owing to their intrinsically low thermal conductivity, which originates from their unique layered structure and van der Waals bonding. InSe, a post-transition metal chalcogenide, also has layered atomic structure and low thermal conductivity. We investigate the effects of S doping of Si-doped InSe, In0.9Si0.1Se. The S-doped In0.9Si0.1Se exhibits enhanced thermoelectric properties, with a higher power factor and lower thermal conductivity compared to Si-doped InSe. A significant increase in carrier mobility has an overall positive effect on the electronic transport properties, resulting in a systematic increase in power factor from 0.05 to 0.15 mW/mK2 with S doping. In addition, the thermal conductivity systematically decreases with S doping owing to additional point-defect scattering. Because of the higher power factor and lower thermal conductivity, the thermoelectric figure of merit of the In0.9Si0.1Se0.9S0.1 sample at 735 K was 0.18, which is 3.6 times that of In0.9Si0.1Se.

Influence of secondary phases of PdTe2 in n-type thermoelectric Cu0.008Bi2Te2.7Se0.3 alloys on their thermoelectric properties was investigated through in situ phase separation by melt spinning process. The phase segregation of PdTe2 in the Cu0.008Bi2Te2.7Se0.3 matrix were successfully induced by using the melt spinning process. Since heterointerfaces of PdTe2 and Cu0.008Bi2Te2.7Se0.3 form potential barriers, low energy carrier filtering effect could be expected; however, the power factor and effective mass decreased with the PdTe2 addition, which implies that the carrier filtering effect did not occur. The potential barrier of 0.06 eV expected at the interfaces between PdTe2 and Cu0.008Bi2Te2.7Se0.3 matrix seems not to induce carrier energy filtering effect. However, further investigation based on single parabolic band model shows that the non-degenerate mobility and quality factor B are enhanced by PdTe2 addition, suggesting that the further optimization of the carrier concentration would increase zT further in PdTe2-added Cu0.008Bi2Te2.7Se0.3 samples. This implies that the favorable carrier filtering effect could be attained by further controlling the optimal carrier concentration even with small barrier heights.

Contact between two-dimensional (2D) transition metal dichalcogenides and certain metals (Au, Pd, Ti, or Pt) results in strong Fermi-level pinning and high resistance. Furthermore, to construct a high-performance device, accurate measurement of the contact resistance and Schottky barrier height (SBH) is crucial. In this study, the SBH and the resistance of a 2H phase few-layer molybdenum telluride (2H–MoTe2) film, which was grown by metal organic chemical vapor deposition, and a Ti/Au electrode were determined by analyzing the high-temperature thermal transmission properties and the transmission line method, respectively. The carrier mobility, ON/OFF ratio, SBH, and contact resistance of the few-layer MoTe2 device, which has p-type behavior with Ti/Au electrode, were found to be 53.7 cm2 V−1 s−1, 3.44 × 106, 163 meV, and 10.2 $${\text{M}}\Omega$$ , respectively.

Metal chalcogenides have attracted attention as potential thermoelectric materials due to their intrinsically low thermal conductivity arising from their layered structure with weak van der Waals atomic bonding. InSe, one of the post transition metal chalcogenides, also has low thermal conductivity and doping of InSe with elements such as Sn, Si, and As is known to improve the electronic transport properties. Herein, we investigated Te doping in Si-doped InSe (In0.9Si0.1Se) and report enhanced thermoelectric properties, mainly the increased Seebeck coefficient due to the increase in effective mass. Due to the increase in effective mass, the magnitude of the Seebeck coefficient systematically increased with Te doping from 234 µV/K to 405 µV/K. Eventually, the zT at 700 K was enhanced from 0.040 for the pristine sample to 0.069–0.096 for the Te-doped samples.

Incorporation of a foreign element is considered as a promising approach to enhance the performance of thermoelectric materials since this can either improve the power factor by a band structure modification or reduce the thermal conductivity by a phonon scattering strengthening. We fabricated the polycrystalline bulk samples of Cu-incorporated Bi0.5Sb1.5Te3 by melt spinning and spark plasma sintering, and evaluated the electronic and thermal transport properties. From the phase analysis and thermoelectric properties measurement, we found that most of the added excess Cu atoms were substituted at a Sb-site and a small amount of Cu was intercalated at the van der Waals gap between quintuple layers. By the formation of two different point defects (substituted Cu and intercalated Cu), the thermoelectric power factor was enhanced because of the increased density of states effective mass, and simultaneously reduced thermal conductivity originated from the intensified phonon scattering and suppressed bipolar contribution. Maximum thermoelectric figure of merit zT of 1.13 was obtained at 400 K.

Cu intercalation is known to be an effective strategy for improving the reproducibility of thermoelectric properties in n-type Bi2Te2.7Se0.3 alloys. In this study, the effect of Cu intercalation on the electronic and thermal properties of n-type Bi2Te2.7Se0.3 polycrystalline alloys was investigated systematically with respect to bipolar conduction and point defect phonon scattering by using the two-band model and Debye–Callaway model. The mobility and concentration of majority carriers (electrons) increased simultaneously while those of minority carriers (holes) decreased with increase in the amount of Cu. Thus, bipolar conduction, which has a detrimental effect on both electronic and thermal properties, was gradually reduced in the Cu-intercalated Bi2Te2.7Se0.3 samples. The reduction of the lattice thermal conductivity was analyzed quantitatively to show that Cu intercalation was also effective for enhancing point defect phonon scattering as interstitials. Thus, Cu intercalation in n-type Bi2Te2.7Se0.3 alloys enhanced the thermoelectric properties by controlling bipolar conduction and phonon scattering synergistically.

Doping is an effective approach to enhance the thermoelectric figure of merit (zT) of thermoelectric alloys by modifying their electronic structure. In this study, we investigated the influence of In doping on the electronic and thermal transport properties of n-type Cu0008Bi2-xInxTe2.7Se0.3 (x = 0, 0.005, 0.01, and 0.015) polycrystalline alloys. The electrical conductivity of the alloys showed a moderate decreased by In doping. The Seebeck coefficient also decreased slightly. The bandgap Eg of the alloys widened slightly according to the Goldsmid–Sharp Eg formula. The band parameters of the conduction and valence bands were estimated using a two-band model. In the case of the In-doped samples, the concentration and mobility of electrons decreased simultaneously, resulting in a reduction in the electrical conductivity. However, the level of bipolar conduction remained unchanged even after doping because of the compensation of Eg widening and the band parameter modification. Meanwhile, the effect of In doping on the thermal conductivity of n-type Cu0.008Bi2Te2.7Se0.3 was found to be insignificant. Consequently, the zT of the alloy increased slightly to 1.12 at x = 0.05, while it decreased at higher doping levels.

Coagulopathy is frequent in septic shock and plays a key role in multiple organ dysfunction. The aim of this study is to investigate application values of thromboelastography (TEG) for outcome in septic shock patients with a normal value of prothrombin time (PT) and active partial thromboplastin time (aPTT). Prospective observational study using 1298 consecutive septic shock patients with TEG at admission was conducted at the emergency department (ED) of a tertiary care hospital in South Korea between 2016 and 2019. After excluding overt-disseminated intravascular coagulation (DIC) defined by scoring system, we included patients with a normal value of international normalized ratio ≤ 1.3 and aPTT ≤ 34 s. The primary outcome was 28-day mortality. 893 patients were included and 129 patients with overt DIC were excluded. Of the 764 remaining patients, 414 (54.2%) patients showed normal PT and aPTT (28-day mortality rate, 11.4%). TEG values such as reaction time, kinetic time (K), alpha angle (α), maximum amplitude (MA) and lysis index (LY 30) showed no significant mean difference between the survivor and non-survivor groups. However, hypocoagulable TEG values such as α 3 and α

Background Screening for osteoporosis with dual-energy X-ray absorptiometry (DXA) is recommended for male HIV-infected patients only above the age of 50. Recently, trabecular bone score (TBS) has been introduced as a novel tool to assess bone microarchitecture using DXA of the lumbar spine. Few studies have reported TBS values in HIV-infected individuals younger than 50 years of age. This study compared TBS values in young males infected with HIV and matched controls, and investigated the associations between TBS and demographic parameters, clinical parameters, and bone mineral density (BMD) scores. Methods A cross-sectional study of BMD and TBS in HIV-infected men (n = 80) aged between 18 and 50 years and age- and sex-matched controls (n = 80) was conducted. Results The proportion of patients with low BMD (Z-score ≤ − 2) was significantly greater among HIV-infected patients than among matched controls (21.3% [17/80] vs. 8.8% [7/80], p = 0.027). Mean TBS values were significantly lower in HIV-infected patients than in controls (1.41 ± 0.07 vs. 1.45 ± 0.07, p = 0.008). In both groups, TBS values were positively correlated with BMD at the lumbar spine, femoral neck, and total hip (p p = 0.04). Conclusion Young men infected with HIV had abnormal bone trabecular microarchitecture, as assessed by both TBS and BMD. TBS values were correlated with both BMD and the duration of TDF exposure.

A retrospective comparative cohort study.To investigate the causes of jack-knife posture (JKP) without proximal junctional kyphosis (PJK) and to compare the causes of PJK and JKP without PJK.PJK causing stooping posture could be inevitable after long instrumented lumbar fusion for degenerative sagittal imbalance. However, few studies have addressed JKP without PJK, which is a different type of sagittal malalignment.Ninety-four adult patients who underwent long instrumented lumbar fusion for degenerative sagittal imbalance were divided into three groups depending on the presence of a postoperative sagittal deformity: JKP, PJK, or none. JKP was defined as a sagittal vertical axis of at least 8 cm anterior to the posterosuperior corner of S1 upper endplate without PJK. PJK was defined as a proximal kyphotic angle ≥10° and at least 10° greater than the preoperative measurement.Seventeen patients (18.1%) showed JKP, and 39 patients (41.5%) showed PJK. The mean age at the surgery of JKP and PJK patients was 70.0 and 65.5 years, respectively (p = .05). JKP developed more frequently if the preoperative pelvic tilt was25° or the sagittal vertical axis was8 cm (p = .048, 0.004, respectively). PJK developed more frequently if the preoperative pelvic tilt was25°, surgically corrected lumbar lordosis was30°, or the lumbar lordosis to thoracic kyphosis angle was0° (p = .002, .010, .031, respectively). JKP was more likely to develop in patients without sacropelvic fixation (p = .042), although they had a more degenerative L5-S1 segment (p = .010).Postoperative sagittal deformity can be classified into two types: JKP and PJK. JKP is caused mainly by hip and back extensor muscle weakness even though the cause of postoperative sagittal decompensation could be multifactorial. However, PJK developed mainly due to spinopelvic malalignment. Therefore, hip and back extensor weakness, which is age-dependent, may explain why older patients experienced more postoperative sagittal deformity.Level IV.

Background: For Grade I degenerative lumbar spondylolisthesis (DLS), both decompression alone and decompression with fusion are effective surgical treatments. Which of the two techniques is superior is still under debate. The purpose of this study was to compare clinical outcomes after decompression alone versus decompression with fusion for Grade I DLS. Materials and Methods: 139 patients who underwent surgery for Grade I DLS at L4-L5 were prospectively enrolled. Decompression alone was used to treat 74 patients, and decompression with fusion was used to treat 65 patients. Six patients in the first group and four patients in the second group were lost during the 2-year followup. Demographic data were recorded. Operation time, perioperative blood loss, total blood transfusion volume, and length of hospital stay were compared between the two groups. Back pain and functional outcomes were evaluated using the visual analog scale (VAS) and the Oswestry Disability Index (ODI), respectively. Results: Baseline demographic data were not different between the two groups. Operation time, blood loss, total blood transfusion volume, and length of hospital stay were all significantly greater in the fusion group than in the decompression group. This would be expected because fusion is the more invasive procedure. VAS scores were not different up until 6 months postoperatively. Twelve months after surgery, however, VAS scores were significantly lower in the fusion group. The same results were shown in terms of ODI. Although ODI decreased in both groups over time, the fusion group showed better functional outcomes than did the decompression group. Conclusions: Although both decompression alone and decompression with fusion improved functional outcomes for Grade I DLS, fusion surgery resulted in better results compared to decompression alone. Therefore, fusion should be considered as the treatment of choice for Grade I DLS.

To the best of our knowledge, there has been no report regarding rheumatoid arthritis associated with spinal neuroarthropathy and combined double-level isthmic spondylolisthesis. Here, we report a rare case of spinal neuroarthropathy with double-level isthmic spondylolisthesis in a rheumatoid arthritis (RA) patient. A 56-year-old female patient under medical treatment for RA during the last 13 years presented aggravating radiating pain to her right lower extremity and a limping gait developed 4 months ago. The disease activity of RA had remained low for a long time. Serial radiographs during last 8-year follow-up showed progressive dislocation at L4–L5 and L5–S1 with double-level isthmic spondylolisthesis and severe destructive status at the last follow-up. The patient underwent decompression and circumferential fusion with sacropelvic fixation and acceptable reduction was obtained. A RA patient with double-level isthmic spondylolisthesis showed a progressive destructive lesion. In addition to clinical presentations, the imaging findings were very similar to ones of spinal neuroarthropathy. The authors conclude that this Grand Round case probably had SNA secondary to RA and that this, combined with two-level isthmic spondylolisthesis, resulted in her rapidly progressing destructive lumbar lesion.

Recently, the improvement in the data communication networks in terms of availability and reliability is emerging as a critical issue. In this context, the high availability and reliability of routers that control data flow and routing path between networks are being recognized as critical problems. Many methods for providing high availability to minimize the loss cost caused by the failure of a router are being studied. This paper analyzed the takeover method proposed in the previous studies to support the high availability of the BGP protocol, and proposed a BGP session takeover method using the virtualization technique to improve the takeover performance.

Nipple reconstruction in implant-based breast reconstruction remains challenging, as the remaining thin skin envelope results in a less projected neo-nipple with a reduced volume. This study presents a modified top-hat flap technique with rolled dermal grafts from the dog-ears of lateral wings for augmenting reconstructed nipples during implant-based breast reconstruction. Between April 2011 and December 2014, among 34 patients who underwent immediate post-mastectomy reconstruction with a direct silicone implant, nipple reconstruction was performed using the modified top-hat flap technique in only 21 patients (group A), whereas 13 patients underwent the modified top-hat flap technique with rolled dermal grafts from the dog-ears of lateral wings (group B). The projection and width of the neo-nipple were measured at the time of surgery and at 1 year post-surgery, respectively. All modified top-hat flaps were successful without any complications. The mean nipple projections at the time of surgery were 0.75 ± 0.107 cm (range 0.5–0.9 cm) and 1.29 ± 0.064 cm (range 1.2–1.4 cm) in groups A and B, respectively (p

In D7 tool steel, which contains high levels of primary carbides, the influence of carbide modification by Ti addition was quantitatively analyzed. Considering the Griffith-Irwin energy criterion for crack growth, the impact energy was evaluated by substituting a microscopic factor of the normalized number density of carbides cracked during hardness indentation tests for the crack length. The impact energy was enhanced with Ti addition because Ti reduced and refined the primary M7C3 carbide phase of elongated morphology, reducing the probability of crack generation.

To assess the efficacy of a novel preemptive multimodal analgesic regimen for reducing postoperative pain and complications after primary lumbar fusion surgery. Preemptive multimodal analgesia is revealed to be an effective alternative to conventional morphine administration providing improved postoperative pain control with diminished side effects. However, an optimal regimen for spinal fusion surgery remains unknown. After Institutional Review Board approval, 80 patients who underwent primary lumbar 4–5 fusion surgery were randomly assigned to receive either only intravenous morphine or a preemptive multimodal (celecoxib, pregabalin, extended-release oxycodone, and acetaminophen) analgesic regimen. Postoperative pain and functional levels were measured by the visual analog scale (VAS) and Oswestry Disability Index (ODI), respectively, and intraoperative blood loss, postoperative Hemovac drain output, and nonunion rates were evaluated for complications. No differences were observed in the patient demographics, intraoperative blood loss, postoperative Hemovac drain output, or nonunion rate between two groups. The VAS and ODI were lower at all postoperative time points, except the ODI on postoperative day 1 in patients randomized to receive the preemptive multimodal analgesic regimen. No major identifiable postoperative complications were observed in either treatment group. The preemptive multimodal analgesic combination in this study appears to be safe and effective after lumbar fusion surgery.

Bisphenol A diglycidyl ether (BADGE) is a widely used coating for food cans and containers and so can be ingested along with contained food; however, measurement of BADGE in biological samples has not previously been performed. This study was conducted to determine serum concentrations of BADGE um and to evaluate the relationship between serum BADGE level and reproductive hormone levels in adult Korean petrochemical factory and non-petrochemical workers (n=223). BADGE and BADGE·2H2O levels in serum were measured using high-performance liquid chromatography-mass spectrometry, and reproductive hormones were analyzed using radioimmunoassay and immunoradiometric assay. The relationships between BADGE and BADGE·2H2O and reproductive hormone levels were assessed using generalized linear models and the distributions of BADGE and BADGE ·2H2O were skewed to the right. Serum BADGE and BADGE·2H2O in non-petrochemicalworkers showed a positive association with follicle-stimulating hormone (FSH, s=0.241; 95% CI, 0.016 to 0.466) but a negative association with estradiol (E2, s=-0.116; 95% CI, -0.210 to -0.022). In this study, the serum BADGE and BADGE·2H2O concentrations were sufficiently high to produce hormonal alterations in adult men.

We report an enhancement of the thermoelectric performance in spark-plasma-sintered polycrystalline p-type Bi0.42Sb1.58Te3 by codoping with Ga and Ag at Bi/Sb-site. Through controlled doping of Ga (n-type) and Ag (p-type), electronic transport properties including the electrical conductivity (~988 S/cm at 300 K) and power factor (~3.91 mW m−1 K−2 at 300 K) could be maintained at values comparable to those of pristine Bi0.42Sb1.58Te3, while the lattice thermal conductivity was significantly reduced due to point-defect phonon scattering originating from the mass difference between the host atoms (Bi and Sb) and dopants (Ga and Ag). Through these synergetic effects, a peak ZT of 1.15 was obtained in Bi0.42Sb1.5535Ga0.025Ag0.0015Te3 at 360 K, and ZT could be engineered to be over 1.0 for a wide temperature range (300 K to 420 K).

We report an enhancement of the thermoelectric figure of merit in polycrystalline In- and Ga-doped Bi0.4Sb1.6Te3 compounds. Via the controlled doping of In or Ga, the lattice thermal conductivity was effectively reduced by strong point-defect phonon scattering while the power factor was not significantly changed due to the similarity of the density of states near the valence-band maximum between undoped and In- or Ga-doped compositions. An enhanced ZT of 1.2 at 320 K was obtained in 0.5 at.% In-doped Bi0.4Sb1.6Te3 compound by these synergetic effects.

Embedding nanosized particles in bulk thermoelectric materials is expected to lower the lattice thermal conductivity by enhancing the degree of interface phonon scattering, thus improving their thermoelectric figure of merit ZT. We have developed a wet chemical process to fabricate Bi0.5Sb1.5Te3-based thermoelectric nanocomposites which include nanometer-sized metal particles. By simple solution mixing of metal acetate precursors and Bi0.5Sb1.5Te3 powders in ethyl acetate as a medium for homogeneous incorporation, it is possible to apply various types of metal nanoparticles onto the surfaces of the thermoelectric powders. Next, bulk Bi0.5Sb1.5Te3 nanocomposites with homogeneously dispersed metal nanoparticles were fabricated using a spark plasma sintering technique. The lattice thermal conductivities were reduced by increasing the long-wavelength phonon scattering in the presence of metal nanoparticles, while the Seebeck coefficients increased for a few selected metal-decorated nanocomposites, possibly due to the carrier-energy-filtering effect. Finally, the figure of merit ZT was enhanced to 1.4 near room temperature. This approach highlights the feasibility of incorporating various types of nanoparticles into an alloy matrix starting by wet chemical routes, which is an effective means of improving the thermoelectric performance of Bi-Te-based alloys.

We present experimental evidence of enhancement of thermoelectric properties in tellurium (Te) nanoparticle-embedded bismuth antimony telluride (BiSbTe) alloys. Bi0.5Sb1.5Te3 films with a high density of Te particles of 10–20 nm size were prepared by growth of alternating multilayers of ultrathin Te and Bi0.5Sb1.5Te3. As the amount of Te nanoinclusions increased up to ∼15%, the Seebeck coefficient and thermoelectric power factor were increased. Based on the concept of band bending at heterointerfaces as a carrier energy filter, the energy relaxation calculation was made to confirm that the Te nanoinclusions result in a carrier energy filtering effect in p-type bismuth antimony telluride. In addition, thermal conductivities were reduced in the Te-embedded samples, permitting possible further enhancement of the thermoelectric figure of merit. The advantages of Te nanoinclusions in p-type Bi0.5Sb1.5Te3alloys on thermoelectric performance are experimentally realized by both electron- and phonon scattering.

Background Spinal metastasis is a common manifestation of bony metastasis, but for surgeons involved in the treatment of individual patients, it is not easy to choose optimal treatments. Various scoring systems have been designed to predict survival periods and to select optimal treatments, but prognosis is still unpredictable. Objectives are to evaluate the efficiency of the predictive value of preoperative Tokuhashi scores for life expectancy in patients with spinal metastasis and to estimate other prognostic factors affected survival of patients with spinal metastasis.

The mammalian brain is far superior to today’s electronic circuits in intelligence and efficiency. Its functions are realized by the network of neurons connected via synapses. Much effort has been extended in finding satisfactory electronic neural networks that act like brains, i.e., especially the electronic version of synapse that is capable of the weight control and is independent of the external data storage. We demonstrate experimentally that a single metal–oxide–metal structure successfully stores the biological synaptic weight variations (synaptic plasticity) without any external storage node or circuit. Our device also demonstrates the reliability of plasticity experimentally with the model considering the time dependence of spikes. All these properties are embodied by the change of resistance level corresponding to the history of injected voltage-pulse signals. Moreover, we prove the capability of second-order learning of the multi-resistive device by applying it to the circuit composed of transistors. We anticipate our demonstration will invigorate the study of electronic neural networks using non-volatile multi-resistive device, which is simpler and superior compared to other storage devices.

Cytomegalovirus (CMV) disease is a frequent opportunistic infection that usually occurs in the late stages of HIV infection as a result of reactivation of a latent infection. We report a case of a 23-year-old man with acute retroviral syndrome complicated by coexisting CMV pneumonia and CMV hepatitis, which were documented by histopathological examination. His CMV pneumonia and hepatitis were assumed to be primary CMV diseases owing to the absence of CMV IgG antibody. To the best of our knowledge, this is the first case of simultaneous CMV pneumonia and hepatitis occurring as primary CMV diseases during primary HIV infection. This case indicates that invasive CMV diseases such as pneumonia and hepatitis should be considered even in patients with primary HIV infection.

Thermoelectric materials, which convert heat into electricity, are much studied for their potential in energy-saving applications — for example as a way of recovering waste heat in cars. At present, though, these materials are inefficient, with very few of them achieving a thermoelectric figure of merit (ZT) above one in the mid-temperature range (500–900 K). Now a figure of merit of 1.48, notably high for a bulk material, is reported for indium selenide crystals (In4Se3–δ) at 705 K. The high thermoelectric performance of this material is related to a Peierls distortion of the crystal lattice at 710 K. This work suggests a new direction in the search for high-performance thermoelectric materials, exploiting intrinsic nanostructural bulk properties induced by charge density waves. Thermoelectric materials, which can convert heat into electricity, are of great interest for energy sustainability. The problem is the low efficiency of these materials, quantified by a coefficient, ZT, which for mid-temperature materials is usually around 1. The realization of a material, In4Se3–δ, which achieves the ZT value of 1.48 at 705 K, could open up a new avenue in the research to generate high ZT materials. Thermoelectric energy harvesting—the transformation of waste heat into useful electricity—is of great interest for energy sustainability. The main obstacle is the low thermoelectric efficiency of materials for converting heat to electricity, quantified by the thermoelectric figure of merit, ZT. The best available n-type materials for use in mid-temperature (500–900 K) thermoelectric generators have a relatively low ZT of 1 or less, and so there is much interest in finding avenues for increasing this figure of merit1. Here we report a binary crystalline n-type material, In4Se3-δ, which achieves the ZT value of 1.48 at 705 K—very high for a bulk material. Using high-resolution transmission electron microscopy, electron diffraction, and first-principles calculations, we demonstrate that this material supports a charge density wave instability which is responsible for the large anisotropy observed in the electric and thermal transport. The high ZT value is the result of the high Seebeck coefficient and the low thermal conductivity in the plane of the charge density wave. Our results suggest a new direction in the search for high-performance thermoelectric materials, exploiting intrinsic nanostructural bulk properties induced by charge density waves.

Background Whether the combination of antimicrobial therapy is a factor in mortality in Pseudomonas aeruginosa bacteremia remains to be elucidated. This study investigated the risk factors for mortality in P. aeruginosa bacteremia patients and the influence of adequate antimicrobial therapy and combination therapy on clinical outcomes. Methods This retrospective study analyzed data of 234 patients with P. aeruginosa bacteremia at a 1,200-bed tertiary teaching university hospital in South Korea between January 2010 and December 2012. Factors associated with mortality were determined. Mortality was compared in patients with adequate empirical and targeted combination therapy, and monotherapy, and inappropriate therapy. Results A total of 141 (60.3%) patients were given appropriate empirical antibiotic treatment (combination therapy in 38 and monotherapy in 103). Among 183 patients (78.2%) who finally received appropriate targeted treatment, 42 had combination therapy and 141 had monotherapy. The percentage of patients receiving empirical combination therapy was slightly, but not significantly higher, in the survivor group than in the nonsurvivor group (17.0% [31/182] vs. 13.5% [7/52], p = 0.74). A similar tendency was demonstrated for targeted combination therapy (19.8% [36/182] vs. 11.5% [6/52], respectively; p = 0.31). However, in a subgroup analysis of data from patients (n = 54) with an absolute neutrophil count less than 500/mm3, the patients who had appropriate empirical or targeted combination therapy showed better outcomes than those who underwent monotherapy or inappropriate therapy (p Conclusions Disease severity was a critical factor for mortality in our patients with P. aeruginosa bacteremia. Overall, combination therapy had no significant effect on 14-day mortality compared with monotherapy. However, appropriate combination therapy showed a favorable effect on survival in patients with febrile neutropenia.

For applications at ultrahigh temperatures the multiphase microstructural options that can be developed in the Mo-Si-B system have demonstrated an effective and attractive balance of essential characteristics. The coexistence of the high melting point (>2100°C) ternary intermetallic Mo5SiB2(T2) phase with Mo provides a useful option for in-situ toughening. A further enhancement is available from a precipitation reaction of Mo within the T2phase that develops due to the temperature dependence of the solubility behavior of the T2phase. However, direct access to Mo+T2microstructures is not possible in ingot castings due to solidification segregation reactions that yield nonequilibrium boride and silicide phases with sluggish dissolution. Alternate routes involving rapid solidification of powders are effective in suppressing the segregation induced phases. The processing and microstructure options can also be augmented by selected refractory metal substitutional alloying, such as the incorporation of Nb, that alters the solubility of the T2phase and the relative phase stability to yield solidification of two phase refractory solid solution + T2structures directly. The observed alloying trends highlight the role of atomic size in influencing the relative stability of the T2phase. A key component of the overall microstructural control and long term microstructural stability is determined by the kinetics of diffusional processes. The analysis of selected diffusion couples involving binary boride and silicide phases has been used to assess the relative diffusivities in the T2phase and coexisting phases over the range of solubility and to provide a basis for the examination of the kinetics of reactions involved in coatings and oxidation.