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Terahertz wave manipulations, especially the phase manipulations, through metasurfaces has attracted considerable interests. Here, we develop a terahertz beam steering device using the liquid-crystal (LC)-integrated programmable metasurface. Specifically, a reflective-type 1 bit metasurface element is designed by employing a multilayer structure composed of metallic back plate-LC-complementary split ring resonator (CSRR). Numerical simulations show that, at the optimized operation frequency of 0.675 THz, the developed metasurface element has a nearly 180° phase difference between unbiased and biased states with close reflection amplitudes. Furthermore, a one-dimensional programmable metasurface array with 32 independently controlled subarrays is designed and fabricated using the lithography technology. Both simulated and measured far-field scattering patterns of the metasurface certify the anomalous beam reflection and wide-angle beam steering performances. Nevertheless, the optimal frequency red shifts to 0.645 THz in the experiment. This work may advance the application of metasurfaces in terahertz beam manipulation devices.

Homogeneous charge compression ignition (HCCI) engines create a more efficient power source for either stationary power generators or automotive applications. Due to the absence of direct actuation of ignition, HCCI based combustion control is quite challenging. For the purpose of control synthesis and design, a crank-angle based dynamic model of an HCCI engine with internal exhaust gas recirculation (EGR) is proposed in this paper. The HCCI autoignition timing is controlled by the amount of internal EGR induced by the cost effective exhaust throttling strategy. The zero dimensional single zone model is developed based on conservation of mass and energy and ideal gas law. The model is comprised of five subsystems: cylinder volume, intake, and exhaust runners along with combustion and heat-transfer models. Inputs to the model include engine speed, intake temperature, fueling rate, intake, and exhaust throttle positions. Outputs of the model contain the pressure, temperature, mass and burned gas fraction in the intake, exhaust and cylinder, air-to-fuel ratio (AFR), heat release rate, combustion phasing, and the indicated mean effective pressure (IMEP). The model is developed based on MATLAB/Simulink and validated against experimental data under steady-state and transient conditions at various intake temperatures, fueling levels, and exhaust throttle positions. Results demonstrate that by changing the exhaust throttle position, the pressure in the exhaust runner is regulated. As a result, the residual gas fraction is altered, leading to changes in mixture temperature and thus control of the HCCI combustion phasing. In the end, closed loop simulation is conducted with a linear quadratic Gaussian (LQG) controller applied to the crank-angle based model for regulation of combustion timing CA50 using exhaust throttle during load (fueling level) changes. In the future, this model can be utilized for control development and hardware in the loop (HIL) simulation.

Four complexes from lanthanides, 3-pyridylacetate, and 1,10-phenanthroline, formulated as [Ln2(3-PAA)2(μ-Cl)2(phen)4](ClO4)2 [Ln = Gd(1), Dy(2), Eu(3), Tb(4), 3-PAA = 3-pyridylacetic acid, phen = 1,10-phenanthroline], were obtained. The four compounds were characterized by IR spectra, thermogravimetric analyses, powder X-ray diffraction, and single-crystal X-ray diffraction. Compounds 1–4 are isomorphous, and they have a dinuclear structure. Magnetic studies reveal that 1 shows the magnetocaloric effect with −ΔSmmax = 19.03 J kg–1 K–1 at 2 K for ΔH = 5 T, and 2 displays a field-induced single-molecule magnet with Ueff = 19.02 K. The photoluminescent spectra of 3 and 4 exhibit strong characteristic emission, which demonstrate that the ligand-to-EuIII/TbIII energy transfer is efficient.

The digital and programmable metasurfaces, as opposed to conventional metasurfaces, offer a more sophisticated method of collaborating information and physics, showcasing several real-time controls to electromagnetic (EM) ways in succinct ways. In this work, we propose a multi-frequency amplitude-programmable (MFAP) metasurface with multiple frequency channels to enhance the presentation and manipulation of EM data. With this metasurface, the reflected amplitudes can be simultaneously and independently encoded between high (digit “1”) and low (digit “0”) levels. The amplitude code is unique, which exhibits both reflection coefficients and radiation patterns to allow for flexible multi-functional EM operations with frequency. For instance, the MFAP metasurface can be used to design innovative communication systems by transmitting various EM signals individually across the channels in time domain. It is also possible to carry out multi-bit transmissions by mixing these frequency channels. By introducing complex coding patterns in space domain, it is possible to manipulate EM powers with greater precision. A square-split ring meta-atom that can achieve stable single-frequency amplitude control and multi-frequency 1 bit amplitude-programmable features is described as a proof-of-concept. Varactors loaded on metallic structures of various sizes are switched between operating states to modify the amplitude codes at each frequency channel. The suggested MFAP metasurface’s validity is confirmed by simulations and measurements from a dual-channel MFAP metasurface prototype.

Background Most previous studies compared survival between left-sided and right-sided colon cancer without adjustment for clinicopathological parameters. We investigated the effect of sidedness on survival among patients with early-stage colon cancer, using a propensity score matching method. Methods The 18 registry custom data within the SEER database were used to identify patients who were diagnosed with colon cancer between 2010 and 2014. A propensity score matching analysis was performed using the nearest neighbor method. Survival was estimated using the Kaplan–Meier method. A Cox proportional hazards model was applied to determine the prognostic factors. Results In the unmatched cohort, 25,094 (35.72%) patients were diagnosed with left-sided colon cancer and 45,156 (64.28%) with right-sided colon cancer. After propensity score matching, each cohort included 5118 patients, and the clinicopathological characteristics were well balanced. In the unmatched cohort, left-sided colon cancer had superior all-cause (χ2=315, Pχ2=43, Pχ2=0.7, P=0.4) and cancer-specific (χ2=0, P=0.96) survival between left and right colon cancer. The Cox model did not indicate sidedness as a prognostic factor. In the subgroup analysis, stage II right-sided colon cancer had a better survival outcome, while stage III left-sided tumors had a better survival outcome. Conclusions After adjusting for clinicopathological characteristics in this study, sidedness showed no impact on survival in early-stage colon cancer. However, sidedness was associated with prognostic differences in stages II and III early-stage colon cancer.

Electromagnetic metasurfaces are structured surfaces consisting of a thin array of subwavelength elements with engineered scattering properties, thus providing a promising means of holographic display by controlling the field distributions. However, the existing metasurface holography has limited capabilities in achieving 3-D fields with simultaneous features of high spatial resolution and energy efficiency due to the design methods. In this work, we present a transmissive metasurface to achieve polarization-dependent field distributions in 3-D space with both high resolution and efficiency. In the design, a new method that utilizes dyadic Green’s function (DGF) as the rigorous propagator is used. Using the method, the sources and fields are linked directly and can be located on arbitrary 3-D points with the intermediate spaces being equal or unequal. The design is successfully validated by full-wave simulations and experimental measurements. The broadband simulation results indicate that the design has a bandwidth of 0.8 GHz. This work demonstrates a feasible and simple route of field synthesis for real-world applications that require high resolution, high efficiency, and 3-D scenarios.

A new family of lanthanide complexes based on a tetrazole-1-acetate ligand and a 1,10-phenanthroline co-ligand were synthesized and characterized by IR spectroscopy, thermogravimetric analyses, powder X-ray diffraction and single-crystal X-ray diffraction, and their formula is [Ln2(μ-Cl)2(1-tza)2(phen)4](ClO4)2 [Ln = Eu (1), Tb (2), Gd (3), Dy (4); 1-Htza = tetrazole-1-acetate, phen = 1,10-phenanthroline]. They show dinuclear structures bridged by mixed μ-COO−1-tza and μ-Cl−. The solid-state luminescence emission properties of 1 and 2 exhibit the characteristic emission bands of Ln cations with a lifetime of 1.49 ms and 0.20 ms, respectively. Magnetic studies reveal that 3 shows a magnetocaloric effect with −ΔSmmax = 18.5 J kg−1 K−1 at 3 K for ΔH = 5 T and 4 displays a single-molecule magnet behaviour with Ueff of 15.19 K.

BackgroundNeoadjuvant intraperitoneal and systemic chemotherapy (NIPS) has shown promising results in gastric cancer (GC) with peritoneal metastasis. However, clinical practice experience of NIPS is still lacking in China. In this study, we investigate the efficacy and safety of NIPS in Chinese patients.MethodsEligible patients received NIPS every 3 weeks. Gastrectomy was performed for patients who met the criteria of conversion surgery. The primary end point was 1-year overall survival (OS) rate. Secondary end points were the response rate, toxic effects, conversion surgery outcomes and median survival time (MST).ResultsSixty-seven patients were enrolled. The primary endpoint was achieved with 1-year OS rate reached 67.2% (95% CI, 56.8%-79.4%). Conversion surgery was performed in 42 patients (62.9%), and R0 resection was achieved in 23 patients (54.8%) with the MST of 31.3 months (95% CI, 24.3-38.3). And the MST was 19.3 months (95% CI, 16.4-22.2) for all patients. Toxicity and surgical complications were well-tolerated. Moreover, sex, R0 resection, pathological nodal stage and tumor regression grade (TRG) were independent prognostic factors for patients who underwent conversion surgery.ConclusionThe NIPS is effective and safe in treating GC patients with peritoneal metastasis. Male patients, patients who underwent R0 resection, patients with ypN0-1 or TRG 1 after conversion surgery are more likely to benefit from the NIPS.Clinical Trial Registrationhttp://www.chictr.org.cn/, identifier https://clinicaltrials.gov/ ().

Direction-of-arrival (DOA) estimation is one of the most critical technologies of radar, remote sensing, and wireless communications. The traditional DOA estimation is closely related to phased array antennas, which require complicated and expensive hardware and high-power consumption. Metasurface can manipulate electromagnetic waves without using massive transceivers, which makes it possible to realize antenna arrays in a cost-effective way. Here, we propose a strategy of DOA estimations by using a time-domain-coding digital metasurface and a single receiver. Specifically, the incident wave on the metasurface is modulated by the time-domain orthogonal codes impressed on the meta-atoms, and their amplitude and phase distributions are precisely retrieved from the signals detected by the receiver antenna. The effectiveness and accuracy of the proposed strategy are verified by experiments on a two-dimensional metasurface with individually addressable meta-atoms. The strategy features low cost and high flexibility and will facilitate various wireless applications.

AIMS To investigate the prevalence of overactive bladder (OAB) and assess its risk factors in 5- to 14-year-old Chinese children. METHODS A cross-sectional study of OAB prevalence was performed by distributing 11 800 anonymous self-administered questionnaires to parents in five provinces of mainland China from July to October 2018. The questionnaires included questions on sociodemographics, history of urinary tract infection (UTI), lower urinary tract symptoms (LUTS), family history of LUTS, bowel symptoms, and details about the elimination communication (EC) start time. OAB was defined as urgency and increased the daytime frequency with or without urinary incontinence. RESULTS A total of 10 133 questionnaires qualified for statistical analysis. The overall prevalence of OAB was 9.01% and decreased with age, from 12.40% at 5 years to 4.55% at 14 years (χ2 trend = 88.899; P

Exogenous enzymes, including protease, lipase, carbohydrate enzyme and phytase, are widely used as additives in fish feed worldwide. The chemical effects of these enzymes are well understood; however, their benefits to fish remain controversial. This review aimed to explore the current state of knowledge on the impacts of exogenous enzymes on finfish aquaculture, and demonstrate the application of exogenous enzymes as a safe and efficient bio‐additive to regulate growth performance, digestibility, feed utilization, whole‐body composition and immune performance of fish, and reduce phosphorus pollution into environment. Overall, based on the current knowledge and information gathered in this review, it is clear that the research on exogenous enzyme supplementation in finfish aquaculture is not extensive. It may be significant to increase research on this subject in future because it could broaden the application of exogenous enzyme use in diets where they cannot be applied currently.

Antennas and metasurfaces have enabled a number of far-field manipulation functions. According to the addition theorem of multipoles, near fields have richer spatial spectra than far fields; hence, in the near-field region, it is easier to achieve complex manipulations on field distributions. In this paper, an algorithm is presented to synthesize the near fields of source arrays. Given target distributions of near-field intensities and also predefined source magnitudes, the algorithm will find the needed source phases, which can then be applied on active antenna arrays and passive metasurfaces to induce the target distribution of fields. The algorithm adopts the dyadic Green’s function as the propagator, and hence, it naturally takes account of the near-field and vector properties of electromagnetic fields. As a typical application of the algorithm, an example is given to obtain the excitation phases of a dipole array, which is then physically imitated by a coding metasurface. Experimental measurement is performed and the result proves the validity of the algorithm. From the perspective of information metasurface, the algorithm finds the phase-coding pattern of metasurface to achieve specific functions.

To describe the application of reversed contralateral distal femoral locking compression plate (DF-LCP) inserted through a progressive and intermittent drilling procedure in the treatment of osteopetrotic subtrochanteric fracture (OSF).Three patients (one male and two females with an average age of 45.33 ± 11.09 years) with OSF hospitalized between September 2015 and September 2020, were included in this present study. Lateral approach was applied in all patients who accepted open reduction and internal fixation (ORIF) with a reversed contralateral DF-LCP inserted through a progressive and intermittent drilling procedure. The operation time and intraoperative blood loss were recorded to evaluate the efficiency of this surgical method. Physical examination and imaging examination of the fracture site were used to evaluate the fracture union status, the position and stability of the implant, and the alignment of the injured limb at 1, 3, 6, and 12 months after operation, then a subsequent visit was conducted at least once a year. Harris Hip Score (HHS) was used to evaluate the hip joint function at 6 and 12 months after operation.The average operation time was 140 ± 21.60 min (110, 160, and 150 min); The average intraoperative blood loss was about 333.33 ± 23.57 ml (300, 350, and 350 ml). The average follow-up time was 22.33 ± 7.41 months (29, 26, and 12 months). All patients achieved bone union with an average time of 6.67 ± 0.94 months (6, 8, and 6 months). At the time of 6 months after operation, case 1 and 3 were almost pain-free and could walk with full weight bearing while case 2 could walk only with partial weight bearing using a crutch. The HHS scores of cases 1, 2, and 3 were 84/100, 74/100, and 92/100, respectively. At the follow-up at 12 months after operation, the HHS score improved to 91/100, 81/100, and 96/100, respectively. The contralateral incomplete old subtrochanteric fracture was deteriorated in case 1 at 26 months after operation. After 3 months of limited weight bearing using a crutch, bone union was verified in radiograph imaging. Fresh contralateral subtrochanteric fracture occurred in case 2 at 26 months after operation, which was treated using a similar surgical approach, and its clinical outcome is under follow-up. Moreover, no perioperative complications including operation-related death, vascular/nerve injury, deep venous thrombosis, pulmonary embolism, and incision infection, and long-term complications involving malunion, nonunion, implant failure, ankylosis, heterotopic ossification, osteonecrosis, and osteomyelitis were identified.The application of reversed contralateral DF-LCP in OSF is practicable and reliable. Progressive and intermittent drilling is a safe and efficient method for implant insertion in this complicated situation.

In this study, we reported the complete chloroplast genome of Fortunella crassifolia Swingle using the HiSeq-4000 sequencing. The chloroplast genome size is 160,229 bp, which consists of a large single-copy region (87,774 bp), a small single-copy region (18,721 bp), and a pair of IR regions (26,867 bp). The chloroplast genome contains 114 unique genes, including 80 protein-coding genes, 30 tRNAs, and 4 rRNAs. Phylogenetic maximum likelihood analysis showed that F. crassifolia was closest to Hongkong kumquat (F. hindsii). The complete chloroplast genome would be subsequently used for citrus species researches.

We propose to systematically investigate the loss mechanism in spoof surface plasmon transmission lines (SSP-TLs) associated with surface-mounted resistors, by numerical simulation and circuit topology modeling, with the experimental validations. Distorted dispersion and loss curves introduced by the resistors are simultaneously predicted by the numerical results and interpreted by the circuit topology model. Attenuators constructed by periodically loaded resistors and T-type networks are designed according to the circuit topology model, and validated by both simulation and experiment results; hence, significant and controllable losses are achieved in a deep-subwavelength scale. The proposed structures and methods enable insightful understanding of the SSP-TLs and hold promise in other lossy SSP device study and design.

Recent advances of space-time-coding digital metasurfaces demonstrate powerful capabilities in the generation of nonlinear harmonics and the accurate control of the corresponding wavefronts. However, to date the near field manipulation and the experiment characterization are still not explored. In this paper, we propose a space-time-digital coding metasurface to realize accurate manipulation of the near fields at the fundamental and + 1 st ( − 1 st) harmonics simultaneously, by properly controlling the initial phase and time delay of the time varying reflectivity. A novel mapping system is established to measure the nonlinear near field distributions of multiharmonics. Both the simulation and experimental results demonstrate the validity of the proposed method.

Purpose: To investigate the prevalence of spina bifida occulta (SBO) and its relationship with the presence of overactive bladder (OAB) in middle-aged and elderly people in China. Methods: A cross-sectional community-based survey was carried out at 7 communities in Zhengzhou City, China from December 15, 2013 to June 10, 2014, where residents aged over 40 years were randomly selected to participate. All of the participants underwent lumbosacral radiographic analysis and relevant laboratory tests. A questionnaire including basic information, past medical history and present illness, and the OAB symptom score was filled out by all participants. Chi-square tests and logistic regression were used for data analysis with a P-value of 0.05). In men, age, SBO, and constipation were risk factors for OAB (P0.05). In women, age, SBO, and HCI were risk factors for OAB (P0.05). Conclusions: The prevalence of SBO is high and it is related to OAB in middle-aged and elderly people in China.

MicroRNAs (miRNAs) are a class of short, evolutionary conserved non-coding RNA molecules, which are shown as the key regulators of many biological functions. External stress can alter miRNA expression levels, thereby changing the expression of mRNA target genes. Here, we show that miR-21 is involved in the regulation of alkalinity tolerance in Nile tilapia. Alkalinity stress results in a marked reduction in miR-21 levels. miR-21 loss of function could affect ion balance regulation, ROS production, and antioxidant enzyme activity in vivo. Moreover, miR-21 knockdown protects cell against alkalinity stress-induced injury in vitro. miR-21 directly regulates VEGFB and VEGFC expression by targeting the 3′-untranslated regions (UTRs) of their mRNAs, and inhibition of miR-21 significantly increases the levels of VEGFB and VEGFC expression in vivo. Taken together, our study reveals that miR-21 knockdown plays a protective role in alkalinity tolerance in tilapia.