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Cu 1.97 Se- x wt. % In 2 O 3 (x = 0–1) bulk composites are fabricated by combining high-temperature melting and spark plasma sintering technology. The doping of In3+in Cu vacancies tunes the carrier concentration and modifies the band structure of Cu 1.97 Se. Additionally, excessive In 2 O 3 particles benefit the construction of multiple lattice defects to strengthen phonon scattering and suppress the long-range migration of Cu ions, resulting in obviously reduced thermal conductivity and improved service stability. Ultimately, a peak ZT value of 1.43 is obtained at 873 K for the Cu 1.97 Se-0.5 wt. % In 2 O 3 bulk specimen, which is almost 150% higher than that of pristine sample. The thermoelectric conversion efficiency and mechanical properties of the composites sample are also measured. The results suggest that Cu 1.97 Se-based nanocomposites offer potential for use in power generation device assembly. [ABSTRACT FROM AUTHOR]

Patients presenting breast actinic damage or implant-related complications require an autologous approach to breast reconstruction. However, when they are not good candidates for microsurgical procedures, alternative solutions must be sought. Latissimus dorsi (LD) is a workhorse flap in breast reconstruction, but often the amount of skin and volume achievable are insufficient. Taking inspiration from the Kiss flap concept, the authors hereby describe the " Kiss " LD flap to achieve totally autologous breast reconstruction. A prospective service evaluation of all patients who underwent breast reconstruction with Kiss LD flap between 2018 and 2020 was performed. Patient demographics and operative variables were recorded, together with early and late complications. Patient satisfaction and quality of life were registered using the latest BREAST-Q reconstruction module, which includes specific LD scales. The questionnaire was administered to patients preoperatively and six months postoperatively. Thirty patients underwent total autologous breast reconstruction with Kiss LD flap. Breast cancer and breast sarcoma resection were followed by reconstruction. The timing of reconstruction was immediate in 3 cases and delayed in 27 cases. No major complications nor total flap loss were registered. BREAST-Q scores postoperatively were significantly higher than the preoperative ones in every domain (p<0.0001) except for the physical well-being of back and shoulder, where the scores differed slightly and non-significantly (p=0.05). The Kiss LD flap allows to harvest a large amount of skin to restore the breast envelope and a considerable volume to reconstruct the breast mound in a completely autologous procedure. [ABSTRACT FROM AUTHOR]

Objectives: Sleep has been closely linked to breast cancer risk. However, the association between sleep and breast cancer prognosis remains unclear. The aim of this study was to evaluate the separate and joint effects of multiple sleep characteristics on breast cancer prognosis among Chinese women.Methods: A total of 1580 breast cancer patients were recruited between October 2008 and December 2014 and followed up until December 31, 2017 in Guangzhou. Multivariate Cox models were conducted to estimate the hazard ratios (HR) and 95% confidence intervals (95%CI) for breast cancer prognosis in association with sleep characteristics.Results: Long sleep duration at night (>9 h) (HR = 2.33, 95%CI: 1.01-5.42), poor sleep quality (HR = 3.08, 95%CI: 1.74-5.47), and impaired daytime function (HR = 2.49, 95%CI: 1.65-3.79) after diagnosis were associated with an increased risk of breast cancer progression. Both short sleep duration (<6 h) (HR = 2.00, 95%CI: 1.06-3.77, Pinteraction = 0.011) and long sleep duration (>9 h) (HR = 4.69, 95%CI: 1.31-16.78, Pinteraction = 0.187) increased the progression risk only among patients with impaired but not normal daytime function. In addition, daytime napping significantly modified the effect of short sleep duration on the progression (HR = 3.55, 0.59, 95%CI: 1.55-7.97, 0.23-1.53 for patients without and with daytime napping, respectively, Pinteraction = 0.005). Stratification results suggested that the associations were more evident among pre-menopausal patients, although no significant interaction was observed.Conclusion: Our findings suggested that inadequate sleep duration to feel one's best and poor sleep quality after diagnosis were associated with an increased risk of breast cancer progression, particularly for pre-menopausal women. [ABSTRACT FROM AUTHOR]

Phthalate esters (PAEs) and parabens are environmental pollutants that can be toxic to human health. Herein, a cold-adapted esterase from the Mao-tofu metagenome named Est1260 was screened for its PAE-hydrolyzing potential in cold temperatures. The results showed that purified Est1260 could degrade a variety of PAEs and parabens at temperatures as low as 0 °C. After careful analysis of the structural information and molecular docking, site-saturation mutation was conducted at the identified hotspots. Protein expression of variant A1B6 doubled, and its thermal stability significantly improved (24 times) without sacrificing activity at low temperatures. In addition, Est1260 and its variants were activated by NaCl and demonstrated resistance to high concentrations of saline (up to 5 M), making it a potential biocatalyst for bioremediation of PAE and paraben-polluted environments. [Display omitted] • Cold-adapted esterase Est1260 can degrade phthalate esters and parabens at temperatures as low as 0 °C. • Thermal stability of Est1260 can be increased without sacrificing its activity. • Est1260 and variants are activated and highly stable at high concentrations of NaCl. [ABSTRACT FROM AUTHOR]

Summary Objective The popularity of the superficial circumflex iliac artery perforator (SCIP) flap has been limited by factors such as variable vascular anatomy and short arterial pedicle. This article aimed to delineate flap design and harvest strategies based around either the proximal or distal perforators of the superficial circumflex iliac artery (SCIA) and propose a set of strategies that can help deal with the limitations of the flap. Method From August 2011 to June 2015, the SCIP flap was used in 80 patients for soft tissue defects at our institution. We utilized vessel imaging navigation to get a detailed overview of the vascular anatomy preoperatively. Flaps were designed on the basis of either the proximal or distal perforators of the SCIA. Backup strategies and surgical maneuvers were suggested to solve the problems that emerged during surgery. Results In total, 51 flaps were raised on the basis of the proximal perforators of the superficial branch of the SCIA, whereas 25 cases were based on the distal perforators from the deep branch, and in four cases, the pedicle was switched to the superficial inferior epigastric artery. In eight cases, the arterial pedicle lengthen technique was applied with a maximum length of 10 cm. All donor sites were closed directly with inconspicuous scars. Conclusion These surgical strategies simplified the intraoperative decision-making and overcame the shortcomings of the SCIP flap. We believe that the SCIP flap has a great potential to become a new workhorse flap in the field of reconstructive surgery. [ABSTRACT FROM AUTHOR]

Dissipative particle dynamics with energy conservation (eDPD) is developed to simulate fluid-solid conjugate heat transfer in a microchannel. A temperature reset region placed ahead of a parallel-plate microchannel and a periodic boundary condition with a body force applied in the streamwise direction are used to generate the hydrodynamically developed, thermally developing flow. To insure the temperature and heat flux continuities at the fluid-solid interface, heat transfer in the fluid zone and solid zone is solved entirely, and an equivalent mesoscopic heat friction coefficient is proposed in the eDPD simulation. The results by eDPD method with the new numerical schemes agree well with those by the finite volume method (FVM) for the predictions of heat transfer in a thick-wall microchannel. [ABSTRACT FROM AUTHOR]

Phonon heat transport in thin films is solved by using dissipative particle dynamics with energy conserving (eDPD), and the size effect on thermal conductivity is analyzed. When the thickness of a film is comparable with the phonon mean free path, boundary scattering becomes dominant. To incorporate both the phonon–phonon scattering effect and phonon-boundary scattering effect, we adopt a particle–particle collision flux model and a particle–wall collision flux model in eDPD. Using these models, we investigated the heat transport between two parallel and infinite plates for 0.1 < Kn < 10 where the heat transport is both ballistic and diffusive. The temperature jump is observed at the boundaries and the temperature profiles are in good agreement with the solution to the equation of phonon radiative transport (EPRT). Moreover, we vary the thickness of the film and calculate the corresponding effective thermal conductivity to investigate the size influence. The present results are compared with the simple analytical solution based on Matthiessen’s rule and the effective thermal conductivity equation derived from the EPRT and it is found that the effective thermal conductivity can be predicted correctly by eDPD. [ABSTRACT FROM AUTHOR]

Purpose The piezoelectric device allows bone cutting without damaging the surrounding soft tissues. The purpose of this study was to assess the role of this surgical instrument in paediatric craniofacial surgery in terms of safety and surgical outcomes. Methods Thirteen consecutive paediatric patients underwent craniofacial Le Fort osteotomies type III and IV. The saw was used on the right side in seven patients and on the left side in six patients; the piezoelectric instrument was used on the right side in six patients and on the left side in seven patients. Intraoperative blood loss, surgical procedure length, incision precision, postoperative haematoma and swelling, and nerve impairment were evaluated to compare the outcomes of both procedures. Results A longer surgical procedure was observed in 28% of the patients when using the piezoelectric device ( p = 0.032), with an intraoperative blood loss reduction of 18% ( p = 0.156). Greater precision in bone cutting was reported, together with a reduction in the requirement to protect and incise adjacent soft tissues during piezoelectric osteotomies. There was a lower incidence of postoperative haematoma and swelling following piezo-osteotomy, and a significant reduction in postoperative nerve impairment ( p = 0.002). Conclusions The ultrasonic surgical device guaranteed a clean bone cut, preserving the integrity of the adjacent soft tissues beneath the bone. Although the time required for a piezoelectric osteotomy was longer, the total operation time remained approximately the same. In conclusion, the device's lack of power appears to be a minor problem compared with the advantages, and an ultrasonic device could be considered a valuable instrument for paediatric craniofacial advancement. [ABSTRACT FROM AUTHOR]

Nanostructuring is a conventional approach to decrease thermal conductivity, nevertheless, the effect of grain boundaries on scattering phonon is limited. Herein, a new approach of constructing complex nanostructures is proposed. The copper sulfides-based nanocomposites with high thermoelectric properties and phase stability were fabricated by combining with solid-state reaction and spark plasma sintering techniques. The main phase of Cu 12 Sb 4 S 13 and Cu 1.96 S with complex nanostructures is obtained by introducing CoSb 3 additive to Cu 1.8 S matrix. Hole concentration in p-type composites is tailored by regulating Cu vacancies concentration and Co3+ doping in Cu+ sites, resulting in the significantly enhanced Seebeck coefficient and carrier thermal conductivity reduction. Furthermore, an ultralow thermal conductivity of 0.47 W m−1 K−1 at 773 K is achieved due to the tuned carrier concentration and the enhanced phonons scattering by continuous nanopores, extra phase interfaces and nanoprecipitates. The record high ZT of 1.6 is achieved at 773 K in Cu-S based thermoelectric material system for the composite specimen, namely Cu 1.8 S-5 wt.% CoSb 3. Our result provides a new strategy to construct complex nanostructures and realize spontaneous composition regulation in improving TE performance of copper sulfide-based materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose To investigate the application of the medial sural artery perforator flap in hemiglossectomy reconstruction and evaluate the value of preoperative computed tomographic angiography (CTA) for perforator location. Patients and Methods Nine patients received medial sural artery perforator flaps for tongue reconstruction from August 2013 to January 2014. Of the 9 patients, 5 were male and 4 were female, with a mean age of 51 years (range 22 to 67). The number, location, and course of the perforators were measured on the CTA preoperatively. Results Of the 9 medial sural artery perforator flaps, 8 survived and 1 had developed necrosis. Thirteen perforators had been visualized by CTA, and 10 of these were used in the operation. No significant difference was found between the CTA location and the intraoperative findings in the perforators' distribution. The mean diameter of the medial sural artery was 1.0 ± 0.3 mm and of the concomitant vein was 2.0 ± 0.7 mm. The mean pedicle length was 9.7 ± 1.0 cm, with 5.1 ± 1.7 cm of the main trunk and 4.6 ± 2.1 cm of the perforator. The average number of muscular vessel branches was 23.9 ± 6.9, with 12.2 ± 5.1 from the main trunk and 10.1 ± 4.4 from the perforators; 1 (10%) perforator was septocutaneous and 9 (90%) were myocutaneous. Conclusions The medial sural artery perforator flap is appropriate for medium-size tongue defect reconstruction, with a long pedicle of matching caliber, adequate tissue volume, and minimal donor site morbidity. CTA is a valuable and necessary method for preoperative assessment of the perforator's location. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mutant from XYL10C_ΔN with improved catalytic activity was obtained through protein engineering. • Synergistic hydrolysis with the engineered xylanase and cellulase excelled other enzyme treatments. • Seawater immersion was helpful for biomass hydrolysis as chemical pretreatment. • Ramulus mori was converted into fermentable sugars with lower energy consumption. Biorefinery of Ramulus mori with lower energy consumption through improved enzyme and pretreatment strategies was reported. Directed evolution and saturation mutagenesis were used for the modification of xylanase, the yield of fermentable sugars and the degree of synergy (DS) were determined for different pretreatment (seawater/non-seawater) and enzyme treatment groups (xylanase/cellulase/co-treatment). The dominant mutant I133A/Q143Y of Bispora sp. xylanase XYL10C_ΔN was obtained with improved specific activity (1860 U/mg), catalytic efficiency (1150 mL/s∙mg) at 40 °C, and thermostability (T 50 increased by 7 °C). With the pretreatment of seawater immersion, the highest yield of fermentable sugars for Ramulus mori at 40 °C reached 199 μmol/g when hydrolyzed with cellulase and I133A/Q143Y, with the highest DS of 2.6; this was 4.5-fold that of the group hydrolyzed by cellulase alone with non-seawater pretreatment. Thus, bioconversion of reducing sugar from Ramulus mori was improved significantly at lower temperatures, which provides an efficient and energy-saving way for biofuel production. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Rhinophyma is characterized by slowly progressive tumour-like enlargement of the nasal skin that will not resolve spontaneously. Though its treatment consists of surgical removal of the hyperplastic alterations, in the literature there is not general agreement about the best method. We presented our experience with two different treatment modalities such as decortication by scalpel and CO2 laser treatment. Methods: The authors reviewed the long-term results of 67 patients affected by rhinophyma treated with two different methods between 1996 and 2011. Outcomes were determined by case notes, clinical review and patient satisfaction questionnaire. Results: Forty-five cases were treated with tangential excision and 22 with a CO2 laser. Minor complications, including scarring and hypopigmentation, were seen in 6 patients. All patients were satisfied with their outcomes at the follow-up visit, and no major complications were detected during follow-up. Conclusion: Both tangential excision and carbon dioxide laser are well-established, reliable procedures for rhinophymaplasty that preserve the underlying sebaceous gland fundi allowing spontaneous re-epithelialization without scarring with similar outcomes and high patient satisfaction. The original nose shape and nearly normal skin surface texture are preserved by quickly removal of the hypertrophic tissue sparing the pilosebaceous tissue. The CO2 laser is more capital intensive and results in higher fees compared with the simpler cold blade tangential excision. In our experience the ease of use, accuracy and precision of the lasers offer is not justified by the increased costs. [Copyright &y& Elsevier]

Abstract: Using Rytov approximation and modified von Karman spectrum model of the index-of-refraction, the detection probability of single-photon beam propagation in a atmospheric turbulence communication channel is investigated and developed. In this research, the single-photon beam is assumed as a pulse beam which has an initial Gaussian temporal shape of the pulse and a Laguerre–Gaussian fundamental-model spatial distribution. It is found that in order to obtain the messages probability greater than or equal 0.1, we should encode and dispatch 66680 photons in identical information carriers at the transmitting side, and the radius of the detector at the receiving plane must be at least up to 0.4m when the photons propagate in a turbulent atmosphere communication channel. [Copyright &y& Elsevier]

Objective To evaluate the application of transvaginal hydrolaparoscopy for exploration of the pelvic cavity exploration in infertile women. Study design A total of 510 infertile women were included in this study from May 1st, 2009 to April 30, 2012 in the clinic of the Hebei Research Institute for Family Planning. Results In 495 of 510 of the patients (97.06%), a successful operation was achieved at the first puncture. Of these 495 patients, 286 (57.78%) showed bilateral patency. Completely normal tubo-ovarian and pelvic structures were observed only in 79 patients (15.96%): 16 patients (3.23%) had bilateral tube obstruction, 18 (3.64%) had hydrosalpinx, and 8 (1.62%) had fimbrial stenosis. Pelvic abnormalities occurred in 240 patients (44.04%), including bilateral and/or unilateral tubo-ovarian adhesions in 80 patients (16.16%) and 160 (32.32%) found with adhesions in other parts of the pelvic cavity. Pelvic endometriosis was found in 82 patients (16.57%) and 19 (3.84%) had two or more lesions in the pelvic cavity. In addition, 9 cases (1.82%) of ovarian cysts, 7 (1.41%) of bilateral vesicular appendices and 43 cases (6.69%) of a unilateral vesicular appendix were observed. In addition, convoluted tubes such as bent or twisted tubes were found in 4 cases of bilateral fallopian tube occlusion patients (0.81%) and 17 cases of unilateral tubal occlusion patients (3.43%). Conclusions Transvaginal hydrolaparoscopy is a feasible, safe, and cost-effective microinvasive technique. This technique can be considered as an alternative procedure for evaluating female infertility. [ABSTRACT FROM AUTHOR]

SnSe materials have garnered significant interest due to the intrinsic low thermal conductivity. However, its limited electrical conductivity hinders their practical implementation. This study achieved a high ZT value of 1.40 at 773 K in the samples of n-type polycrystalline SnSe 0.95 + x wt% SmCl 3 + y wt% ErCl 3 (x = 0, 0.75, 1.0, 1.25, and 1.5; y = 0, 0.0675, 0.125, and 0.25) since (SmCl 3 , ErCl 3) co-doping decoupled the electrical-thermal transport properties. First, the released electron carrier concentration due to SmCl 3 doping enhanced the electrical transport properties. The SnSe 0.95 + 1.25 wt% SmCl 3 sample exhibited a high power factor of 563 μWm−1K−2 at 773 K. Then, the lattice thermal conductivity markedly decreased with further ErCl 3 doping due to the high-density dislocations and coherent boundary, resulting in effective the phonon scattering. Additionally, the special microtopography was conducive to the decreased lattice thermal conductivity. Therefore, the SnSe 0.95 + 1.25 wt% SmCl 3 + 0.125 wt% ErCl 3 sample achieved a low lattice thermal conductivity value of 0.28 Wm−1K−1 at 773 K. Simultaneously, the (SmCl 3 , ErCl 3) co-doped samples maintained the electrical transport properties than the SmCl 3 -doped samples. Consequently, the SnSe 0.95 + 1.25 wt% SmCl 3 + 0.125 wt% ErCl 3 sample obtained a peak ZT value of 1.40 at 773 K and a competitive average ZT value of 0.37 from 323 to 773 K, and a theoretically calculated conversion efficiency reached 7.2%, which can be applied in the deep space for power generation. This strategy can be utilized to optimize the thermoelectric performance of other thermoelectrical material systems. [ABSTRACT FROM AUTHOR]

Bi 2 S 3 with earth abundant elements has been considered as a potential thermoelectric material. However, it is challenging to make Bi 2 S 3 materials as a promising high-performance thermoelectric device due to its poor electrical transport properties and the coupling between its electrical and thermal transport properties. In this work, we present a new strategy that can significantly improve electrical transport properties, as well as reduce the lattice thermal conductivity by carrier modulation and introducing multi-nano-precipitates in PbBr 2 doped Bi 2 S 3 bulk samples. The electrical conductivity of Bi 2 S 3 was boosted more than one order magnitude higher than that of pristine Bi 2 S 3 after the introducing of Pb and Br, which is demonstrated as the replacement form at the sites of Bi and S, respectively. The resultant Bi 2 S 3 shows an enhanced high power factor of 690 μWm-1K-1 at 598 K, three times higher than that in pristine samples. Besides, the lattice thermal conductivity was reduced to 0.35 Wm-1K-1 at 673 K due to multi-nano-precipitates synergy, i.e., Bi 2 (S 1-x Br x) 3 and (Bi 1-y Pb y) 2 S 3 nanoprecipitates in the Bi 2 S 3 matrix. A high ZT of ~0.8 was therefore achieved at 673 K for Bi 2 S 3 with 1.5 mol% PbBr 2 , a record value in the state-of-the-art Bi 2 S 3 system. A record ZT value in the state-of-the-art Bi 2 S 3 system of ~0.8 was therefore achieved at 673 K for Bi 2 S 3 doped with 1.5 mol% PbBr 2. Image 1 • The Bi 2 S 3 specimens were fabricated via solid-state melting method followed by SPS. • The properties of Bi 2 S 3 was optimized by carrier modulation and introducing multi-precipitates. • Multi-nano-precipitates significantly reduce the lattice thermal conductivity of Bi 2 S 3. • A record ZT of 0.8 is obtained for Bi 2 S 3 doped with 1.5 mol% PbBr 2 at 673 K. [ABSTRACT FROM AUTHOR]

InGaO 3 (ZnO) m (m = 1, 2, 3, 4, and 5) ceramics are a series of n-type oxide thermoelectric materials with layered structures and low thermal conductivities. Herein, InGaO 3 (ZnO) m (m = 1, 2, 3, 4, and 5) ceramics were fabricated by spark plasma sintering (SPS). Two different trends in the thermoelectric properties of the InGaO 3 (ZnO) m (m = 1, 2, 3, 4, and 5) ceramics were observed depending on the odevity of the m value. The InGaO 3 (ZnO) sample exhibited a relatively high electrical conductivity and was therefore selected for vacuum annealing to further improve the electrical transport performance. Oxygen vacancy defects were introduced to the matrix during the annealing procedure, which improved the thermoelectric performance. A maximum ZT of 0.45 was obtained at 973 K for the InGaO 3 (ZnO) sample with a 96 h vacuum annealing treatment, which is 30 times higher than that of the pristine sample. [ABSTRACT FROM AUTHOR]

Digenite (Cu 1.8 S), one of superionic conductors, possesses the exceptional electrical transports performance but unsatisfactory thermal transport properties, which desiderates to be improved to become the candidate for use in the field of thermoelectric application. The porous Cu 1.8 S based composites with Na 2 S polycrystalline bulk samples were prepared via the incorporation of mechanical alloying (MA) and spark plasma sintering (SPS) technique by employing Na 2 S·9H 2 O as a addictive. The hydrate assists to create a porous structure and to refine grains during the fabrication procedure. Benefiting from the strengthened phonons scattering by additional multiscale pores after introducing Na 2 S, the thermal conductivity was dramatically decreased which results in an overall increased thermoelectric efficiency. The optimal thermoelectric figure of merit (ZT) of 0.78 at 773 K is obtained for Cu 1.8 S+2 wt % Na 2 S sample, which is 60% higher than that (0.49) of pristine Cu 1.8 S. [ABSTRACT FROM AUTHOR]

Background Cyclophilin A is identified as a biomarker for inflammation. We elucidated prognostic significance of serum cyclophilin A (CypA) concentrations in acute pancreatitis (AP). Methods In this prospective and observational study, serum CypA concentrations were quantified in 210 AP patients and 100 healthy controls. We recorded local complication, in-hospital mortality and organ failure. Disease severity was assessed using the traditional predictors, namely Acute Physiology and Chronic Health Care Evaluation II score, Ranson score, multiple organ dysfunction score and sequential organ failure assessment score. Results Serum CypA concentrations were significantly lower in controls than in AP group. CypA concentrations after AP were highly correlated with the traditional predictors and other inflammatory mediators, including blood erythrocyte sedimentation rate, procalcitonin levels, white blood cell count and C-reactive protein levels. Serum CypA emerged as an independent predictor for in-hospital local complication, organ failure and mortality. Under receiver operating characteristic curve, serum CypA possessed similar prognostic ability, as compared to the traditional predictors. Its predictive ability was almost similar to that of procalcitonin levels and significantly exceeded those of the other inflammatory mediators. Also, it significantly improved prognostic performance of the traditional predictors. Conclusions Increased serum CypA concentrations have close relation to the severity, inflammation and prognosis, substantializing CypA as a potential prognostic biomarker of AP. [ABSTRACT FROM AUTHOR]

Abstract: Based on the assumption of a pulse laser beam with an initial Gaussian temporal shape and a collimated fundamental-model Gaussian beam, the Rytov approximation and Kolmogorov spectrum model for the index-of-refraction fluctuation of atmosphere, the effect of turbulence on the probability density, acquisition transmittance probability, transmittance probability density, acquisition probability of single-photon propagation in atmospheric communication channel with z-tilt and centroid-tilt aberration corrected are studied theoretically. The probability density, acquisition transmittance probability, transmittance probability density and acquisition probability models for single-photon propagation in uplink path and downlink path are derived. Our results shown that the detection probability and the acquisition transmittance probability of the single-photon are obvious increase, when the beams are propagation in the z-tilt corrected communication channel. [Copyright &y& Elsevier]

The decrease in lattice thermal conductivity is one of the most effective methods for enhancing thermoelectric properties. Achieving lattice thermal conductivity close to the theoretical limit is extremely difficult while maintaining an impressive power factor. By introducing ultrafine bismuth sulfide nanograins, strong phonon scattering was generated by associated multiscale lattice defects to further gain a low lattice thermal conductivity of 0.244 W/m/K approaching Clarke's limitation of 0.242 W/m/K. Simultaneously, the electrical conductivity was increased by S diffusion and suppression of the antisite defects, and a high power factor was maintained to produce an improved ZT peak of 1.2 at 473 K for the Bi 2 Te 2.7 Se 0.3 + 1 wt % Bi 2 S 3 #2 sample. This sample was used to fabricate a small device with a p-leg, and the direct conversion efficiency reached 4.39%. Inverse changes in hardness and Young's modulus in conjunction with Bi 2 S 3 content are first reported in thermoelectric materials, which has potential assistance in synchronously improving their mechanical and thermoelectric properties. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The cutting-edge technologies for pyrazines were reviewed and compared. • Outlining the progress in various microextraction technologies. • Presenting future recommendations for pyrazines pretreatment and determination. Pyrazines are a class of active aromatic substances existing in various foods. The accumulation of pyrazines has an impact on flavor and quality of food products. This review encompasses the formation mechanisms and control strategies of pyrazines via Maillard reaction (MR), including the new reactants and emerging techniques. Pyrazines characteristics are better understood through the developed sample pretreatments and detection methods. Herein, an in-depth review of pretreatments and analysis methods since 2010 is presented to explore the simple, fast, green, and effective strategies. Sample preparation methods include liquid phase extraction, solid phase extraction, supercritical fluid extraction, and microextraction methods such as liquid phase microextraction, and solid phase microextraction, etc. Detections are made by chromatographic methods, and sensors, etc. Advantages and limitations are discussed and compared for providing insights to further studies. [ABSTRACT FROM AUTHOR]

Digenite (Cu 1.8 S) is a subject of increasing interest as a potential p-type thermoelectric material because of its element abundance, low cost and environmental friendliness. However, its thermoelectric properties are limited by high thermal conductivity. In this work, the Cu 1.8 S with x wt% Bi 2 Te 3 (x = 0, 0.5, 1, 3, 5) samples were prepared by combining mechanical alloying (MA) and spark plasma sintering (SPS) technology. The results reveal that Bi 2 Te 3 addition can effectively optimize the thermoelectric properties of Cu 1.8 S materials by tuning the carrier concentration and introducing nanoprecipitates. As a result, the optimal Cu 1.8 S +1 wt% Bi 2 Te 3 sample presents an excellent performance, with relatively high ZT value of 1.1 (at 773 K), which is approximately 2.4 times that of pure Cu 1.8 S. • Cu 1.8 S + x wt% Bi 2 Te 3 (x = 0, 0.5, 1, 3, 5) bulk samples were prepared by mechanical alloying method (MA) and spark plasma sintering (SPS). • A ZT peak reaches 1.1 at 773 K for Cu 1.8 S + 1 wt% Bi 2 Te 3 sample, which is 2.4 times higher than that of pristine. • The average ZT reaches 0.32 in the temperature range from 323 K to 773 K, which is twice of that in undoped Cu 1.8 S sample. [ABSTRACT FROM AUTHOR]