Isotope Effect-Enabled Crystal Enlargement in Metal-Organic Frameworks.

Synthesizing large metal-organic framework (MOF) single crystals has garnered significant research interest, although it is hindered by the fast nucleation kinetics that gives rise to numerous small nuclei. Given the different chemical origins inherent in various types of MOFs, the development of a general approach to enhancing their crystal sizes presents a formidable challenge. Here, we propose a simple isotopic substitution strategy to promote size growth in MOFs by inhibiting nucleation, resulting in a substantial increase in the crystal volume ranging from 1.7- to 165-fold. Impressively, the crystals prepared under optimized conditions by normal approaches can be further enlarged by the isotope effect, yielding the largest MOF single crystal (2.9 cm × 0.48 cm × 0.23 cm) among the one-pot synthesis method. Detailed in situ characterizations reveal that the isotope effect can retard crystallization kinetics, establish a higher nucleation energy barrier, and consequently generate fewer nuclei that eventually grow larger. Compared with the smaller crystals, the isotope effect-enlarged crystal shows 33% improvement in the X-ray dose rate detection limit. This work enriches the understanding of the isotope effect on regulating the crystallization process and provides inspiration for exploring potential applications of large MOF single crystals.

Fabrication of Carboxylate-Functionalized 2D MOF Nanosheet with Caged Cavity for Efficient and Selective Extraction of Uranium from Aqueous Solution.

The efficient removal of radioactive uranium from aqueous solution is of great significance for the safe and sustainable development of nuclear power. An ultrathin 2D metal-organic framework (MOF) nanosheet with cavity structures was elaborately fabricated based on a calix[4]arene ligand. Incorporating the permanent cavity structures on MOF nanosheet can fully utilize its structural characteristics of largely exposed surface area and accessible adsorption sites in pollutant removal, achieving ultrafast adsorption kinetics, and the functionalized cavity structure would endow the MOF nanosheets with the ability to achieve preconcentration and extraction of uranium from aqueous solution, affording ultrahigh removal efficiency even in ultra-low concentrations. Thus, more than 97% uranium can be removed from the concentration range of 50-500 µg L-1 within 5 min. Moreover, the 2D nano-material exhibits ultra-high anti-interference ability, which can efficiently remove uranium from groundwater and seawater. The adsorption mechanism was investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) analysis, and density functional theory (DFT) calculations, which revealed that the cavity structure plays an important role in uranium capture. This study not only realizes highly efficient uranium removal from aqueous solution but also opens the door to achieving ultrathin MOF nanosheets with cavity structures, which will greatly expand the applications of MOF nanosheets.

Fabrication of a Large-Area Flexible Scintillating Membrane for High-Resolution X-ray Imaging Using an AIEgen-Functionalized Metal-Organic Framework.

With the growing demand for X-ray imaging, especially for three-dimensional objects with curved surfaces, a large-area flexible X-ray imaging membrane based on scintillating materials becomes the focus of vigorous investigation. Among the developed scintillators, metal-organic frameworks (MOFs) featuring tunable photophysical properties and marked luminescence stability hold great promise for serving as ideal X-ray scintillators. Here, we report a flexible composite scintillating membrane with superior imaging performance. The membrane is achieved by embedding an aggregation-induced emission (AIE) luminogen (AIEgen, H4ETTC)-functionalized MOF scintillator (Y-PCN-94) into a polymer matrix (PDMS). Notably, Y-PCN-94 exhibits a strong AIE effect under both ultraviolet (UV) light and X-ray irradiation, which is also the first time that the AIE effect was observed in the MOF system under an ionizing radiation field. This also gives the material promising radioluminescence properties, such as a low X-ray detection limit (1.6 µGy s-1) and high imaging resolution (>14.3 lp mm-1), which can be mainly attributed to the combination of the AIE effect and strong X-ray stopping power. This work demonstrates that incorporating AIEgens into MOFs or other frameworks can offer an alternative approach for producing high-performance X-ray scintillators.

Photochromic Uranyl-Based Coordination Polymer for Quantitative and On-Site Detection of UV Radiation Dose.

A highly sensitive detection of ultraviolet (UV) radiation is required in a broad range of scientific research, chemical industries, and health-related applications. Traditional UV photodetectors fabricated by direct wide-band-gap inorganic semiconductors often suffer from several disadvantages such as complicated manufacturing procedures, requiring multiple operations and high-cost instruments to obtain a readout. Searching for new materials or simple strategies to develop UV dosimeters for quantitative, accurate, and on-site detection of UV radiation dose is still highly desirable. Herein, a photochromic uranyl-based coordination polymer [(UO2)(PBPCA)·DMF]·DMF (PBPCA = pyridine-3,5-bis(phenyl-4-carboxylate), DMF = N,N'-dimethylformamide, denoted as SXU-1) with highly radiolytic and chemical stabilities was successfully synthesized via the solvothermal method at 100 °C. Surprisingly, the fresh samples of SXU-1 underwent an ultra-fast UV-induced (365 nm, 2 mW) color variation from yellow to orange in less than 1 s, and then the color changed further from orange to brick red after the subsequent irradiation, inspiring us to develop a colorimetric dosimeter based on red-green-blue (RGB) parameters. The mechanism of radical-induced photochromism was intensively investigated by UV-vis absorption spectra, EPR analysis, and SC-XRD data. Furthermore, SXU-1 was incorporated into an optoelectronic device to fabricate a novel dosimeter for convenient, quantitative, and on-site detection of UV radiation dose.

Association between the rs6313 polymorphism in the 5-HTR2A gene and the efficacy of antipsychotic drugs.

BACKGROUND: Prescribing the optimal antipsychotic treatment to schizophrenia is very important as it is well established that patients have different sensitivity to the available antipsychotic drugs. The genotype of the HTR2A T102C (rs6313) polymorphism has been suggested to affect the efficacy of antipsychotic drugs, but the results of different studies have been inconsistent METHODS: In this study, a meta-analysis was used to ascertain the association between allele and genotype polymorphism of rs6313 and the efficacy of antipsychotic drugs. Related studies publicated from January 1995 to December 2021 were retrieved from PubMed, Embase, ScienceDirect, and Web of Science databases. The correlations between allele and genotype polymorphism of rs6313 and the responder rate and scale score reduction rate of antipsychotics were analyzed. In addition, subgroup analyses were performed on time, drug, and ethnicity. RESULTS: A total of 18 studies were included. The meta-analysis showed that allele and genotype polymorphisms at the rs6313 locus overall were not associated with antipsychotic drug responder rate or scale score reduction rate. Ethnicity subgroup analysis showed that antipsychotic drugs were more effective in patients with allele T in the Caucasian population. Indian patients with the TT genotype had the lowest scale score reduction rate and poor drug treatment effect. East Asian patients with the TC genotype had better treatment effect, whereas in patients with the CC genotype, the treatment was less effective. Drug subgroup analysis showed that patients with the TC genotype treated with clozapine had the highest responder rate and score reduction rate. CONCLUSIONS: The association between rs6313 polymorphism and the efficacy of antipsychotic drugs is mainly influenced by drug and ethnicity. Caucasian patients with the T allele respond better to drug therapy, and Asian patients with TC genotype. The TC genotype was also a good predictor of the efficacy of clozapine treatment.

Assembling a Heterobimetallic Actinide Metal-Organic Framework by a Reaction-Induced Preorganization Strategy.

Periodically arranging coordination-distinct actinides into one crystalline architecture is intriguing but of great synthetic challenge. We report a rare example of a heterobimetallic actinide metal-organic framework (An-MOF) by a unique reaction-induced preorganization strategy. A thorium MOF (SCU-16) with the largest unit cell among all Th-MOFs was prepared as the precursor, then the uranyl was precisely embedded into the MOF precursor under oxidation condition. Single crystal of the resulting thorium-uranium MOF (SCU-16-U) shows that a uranyl-specific site was in situ induced by the formate-to-carbonate oxidation reaction. The heterobimetallic SCU-16-U exhibits multifunction catalysis properties derived from two distinct actinides. The strategy proposed here offers a new avenue to create mixed-actinide functional material with unique architecture and versatile functionality.

Synergistic Effect of Soil Organic Matter and Nanoscale Zero-Valent Iron on Biodechlorination.

Nanoscale zero-valent iron (nZVI) provides a promising solution for organochlorine (OC)-contaminated soil remediation. However, the interactions among nZVI, soil organic matter (SOM), and indigenous dechlorinating bacteria are intricate, which may result in unascertained effects on the reductive degradation of OCs and merits specific investigation. Herein, we isolated an indigenous dehalogenation bacterium (Burkholderia ambifaria strain L3) from a paddy soil and further investigated the biodechlorination of pentachlorophenol (PCP) with individual and a combination of SOM and nZVI. In comparison with individual-strain L3 treatment, the cotreatment with nZVI or SOM increased the removal efficiency of PCP from 34.4 to 44.3-54.2% after 15 day cultivation. More importantly, a synergistic effect of SOM and nZVI was observed on the PCP removal by strain L3, and the PCP removal efficiency reached up to 75.3-84.5%. Other than the biodegradation through ortho- and meta-substitution under the individual application of SOM or nZVI, PCP was further biodegraded to 2,4,6-trichlorophenol (TCP) through para-substitution by the isolated bacteria with the cotreatment of SOM and nZVI. The main roles of the nZVI-SOM cotreatment in the biodegradation included the SOM-facilitated microbial proliferation, the nZVI-promoted microbial transformation of SOM, and the induced higher electron transport capacity of redox Fe-PCP biocycling. These findings provide a novel insight into the action of nZVI in environmental remediations.

Evaluation of pelvic floor muscle function (PFMF) in cervical cancer patients with Querleu-Morrow type C hysterectomy: a multicenter study.

INTRODUCTION: To evaluate the pelvic floor muscle function (PFMF) of cervical cancer patients after type QM-C hysterectomy and to explore the relationship between decreased PFMF and related factors. METHODS: This was a multi-centered retrospective cohort study. 181 cervical cancer patients who underwent type QM-C hysterectomy were enrolled from 9 tertiary hospitals. Strength of PFMF were measured using neuromuscular apparatus (Phenix U8, French). Risk factors contributing to decreased PFMF were analyzed by univariate and multivariate ordinal polytomous logistic regression. RESULTS: Totally 181 patients were investigated in this study. 0-3 level of type I muscle fibre strength (MFSI) was 52.6% (95/181), 0-3 level of type IIA muscle fibre strength (MFSIIA) was 50% (91/181). Subjective stress urinary incontinence was 46% (84/181), urinary retention was 27.3% (50/181), dyschezia was 41.5% (75/181), fecal incontinence was 9% (18/181). ① MFSI: Multivariate ordinal polytomous logistic regression shows that the follow-up time (p < 0.05), chemotherapy and radiotherapy (p = 0.038) are independent risk factors of MFSI's reduction after type QM-C hysterectomy. ② MFSIIA: multivariate ordinal polytomous logistic regression shows that the follow-up time (p < 0.05) are independent risk factors of MFSIIA's reduction after type QM-C hysterectomy. The pelvic floor muscle strength (PFMS) increased after 9 months than in 9 months after operation, which showed that the PFMS could be recovered after operation. CONCLUSIONS: We advocate for more attention and emphasis on the PFMF of Chinese female patients with cervical cancer postoperation. PEKING UNIVERSITY PEOPLE'S HOSPITAL: PFMF after QM-C hysterectomy has not been analyzed by current study. The contribution is that patients with radical hysterectomy should do pelvic floor rehabilitation exercises in 3 months after operation. Clinical Trails NCT number of this study is 02492542.

Intercalation-Activated Layered MoO3 Nanobelts as Biodegradable Nanozymes for Tumor-Specific Photo-Enhanced Catalytic Therapy.

The existence of natural van der Waals gaps in layered materials allows them to be easily intercalated with varying guest species, offering an appealing strategy to optimize their physicochemical properties and application performance. Herein, we report the activation of layered MoO3 nanobelts via aqueous intercalation as an efficient biodegradable nanozyme for tumor-specific photo-enhanced catalytic therapy. The long MoO3 nanobelts are grinded and then intercalated with Na+ and H2 O to obtain the short Na+ /H2 O co-intercalated MoO3-x (NH-MoO3-x ) nanobelts. In contrast to the inert MoO3 nanobelts, the NH-MoO3-x nanobelts exhibit excellent enzyme-mimicking catalytic activity for generation of reactive oxygen species, which can be further enhanced by the photothermal effect under a 1064 nm laser irradiation. Thus, after bovine serum albumin modification, the NH-MoO3-x nanobelts can efficiently kill cancer cells in vitro and eliminate tumors in vivo facilitating with 1064 nm laser irradiation.

Association of pelvic floor function with postoperative urinary incontinence in cervical cancer patients after the radical hysterectomy.

AIMS: To assess the pelvic floor function in cervical cancer patients after radical hysterectomy and its relationship with urinary incontinence (UI). METHODS: Cervical cancer patients who underwent radical hysterectomy were recruited from 18 hospitals in China from January 2012 to March 2015. Pelvic floor examinations were conducted by measuring the pelvic floor muscle strength, fatigue of pelvic floor muscle fatigue, dynamic pressure of vaginal, nerve injury, A3 feedback, muscle potential, static tension, and dynamic tension. Postoperative urinary incontinence (UI) was identified using the International Consultation on Incontinence Questionnaire. Multivariable logistic regression analysis was used to assess the association of pelvic floor function examination results with postoperative UI. RESULTS: Totally 169 patients were included in this study. The prevalence of UI was 39.6% (67/169). The proportion of abnormal fatigue of Type I muscle (64% vs. 36%, p = .04) and abnormal A3 feedback (53.9% vs. 46.1%, p = .03) were higher among patients with postoperative UI compared to those without UI. In the multivariable analysis, abnormal fatigue of Type I muscle (odds ratio [OR] = 3.73, 95% confidence interval [CI]: 1.42-9.84), abnormal A3 feedback (OR = 2.40, 95% CI: 1.04-5.51), and length of resected vagina > 3 cm (OR = 3.44, 95% CI: 1.27-9.31) were associated with postoperative UI. Compared to laparoscopy, laparotomy was less likely to cause postoperative UI (OR = 0.12, 95% CI:0.04-0.33). CONCLUSIONS: The abnormal function of the pelvic floor muscle is related to postoperative UI. Early assessment among these patients is needed to prevent the development of pelvic floor disorder postoperatively.

Adjuncts to pulsed dye laser for treatment of port wine stains: a literature review.

Noninvasive pulsed dye laser is the current gold standard for the treatment of port wine stains. However, most port wine stains are not completely cleared after pulsed dye laser therapy, owing to insufficient photocoagulation and laser-induced vascular regeneration and reperfusion. Several studies have explored approaches designed to improve treatment efficacy. This integrative literature review summarizes the results of clinical and animal studies published between 2004 and 2021. Pulsed dye laser has been administered in combination with photoelectric devices (the neodymium: yttrium-aluminum-garnet lasers, dual-wavelength 1064-/595-nm laser irradiation, fiberoptic Nd-YAG laser, photodynamic therapy, and radio frequency), and drugs (rapamycin, imiquimod, timolol, axitinib, endothelin receptor antagonist, artificial red blood cells and oxymetazoline). The initial results suggest that combination therapy is a direction worth exploring in the future. Further large prospective, blinded and controlled multicenter clinical trials with longer follow-up period are required to obtain more robust evidence.

A multi-centre randomized controlled trial of mobile gynaecological cancer support program for patients with gynaecological cancer undergoing chemotherapy: Study protocol.

AIM: Patients with gynaecological cancer often experience high levels of uncertainty in illness during chemotherapy and report unmet supportive care needs. Mobile applications (apps) are increasing being used as an easily accessible alternative to support these patients, but a lack of rigorous trials have been conducted to explore their effectiveness. Based on Mishel's uncertainty in illness theory, the Mobile Gynaecological Cancer Support (MGCS) program is an app-based program that includes four modules: 1) weekly topics, 2) emotional care, 3) discussion centre and 4) health consultation. The aim of this study is to assess the effectiveness of MGCS for Chinese patients with gynaecological cancer receiving chemotherapy in respect of reducing uncertainty in illness and symptom distress and improving quality of life and social support. DESIGN: A multi-centre randomized controlled trial will be used. METHODS: One hundred and sixty-eight patients with gynaecological cancer commencing chemotherapy will be recruited from three university affiliated hospitals and assigned to the control or intervention group with block randomization. The control group will only receive routine care. The intervention group will access the MGCS program for 24 weeks and receive routine care. Health outcomes will be evaluated at baseline, 12 weeks, and 24 weeks. Repeated measures multivariate analysis of covariance (intention-to-treat) will be used to assess the effectiveness of MGCS. DISCUSSION: This is the first trial to explore the effectiveness of an app-based program for patients with gynaecological cancer using a robust and rigorous study design in China. If effective, this trial will provide evidence for an app-based program to support these patients. IMPACT: The knowledge gained can be applied to develop other culturally appropriate app-based programs for cancer groups worldwide, and provide evidence for health policymakers to allocate more resources and train staff for e-health. TRIAL REGISTRATION: ChiCTR2000033678 (Chinese Clinical Trial Registry Registered 08 June, 2020).

Protoplast fusion between Blakeslea trispora 14,271 (+) and 14,272 (-) enhanced the yield of lycopene and ß-carotene.

Blakeslea trispora, a heterothallic Zygomycota with two mating types (termed "plus" and "minus"), is an ideal source of lycopene and ß-carotene. The lycopene and ß-carotene yields when the two type strains are used for fermentation separately are lower than those when they are joint together. To enhance the yield of lycopene and ß-carotene in B. trispora, protoplast fusion technology was carried out between ATCC 14,271 (+) and ATCC 14,272 (-). After protoplast preparation, protoplast fusion, fusion sorting, fusion regeneration, and high-throughput screening, two fusions (Fu-1and Fu-2) with high lycopene and ß-carotene yields were obtained. The lycopene yields of Fu-1 and Fu-2 were increased to 0.60 mg/gDW and 0.90 mg/gDW, which were respectively 3.62- and 5.44-fold those of 14,271 and 1.76- and 2.64-fold those of 14,272. The ß-carotene yields of Fu-1 and Fu-2 were increased to 22.07 mg/gDW and 36.93 mg/gDW, which were respectively 1.72- and 2.89-fold those of 14,271 and 1.23- and 2.06-fold those of 14,272. In this study, the protoplast fusion technique was successfully used in Blakeslea trispora, providing new ideas for improving lycopene and ß-carotene production.

Three-Dimensional Polycatenation of a Uranium-Based Metal-Organic Cage: Structural Complexity and Radiation Detection.

The potential applications of metal-organic cages (MOCs) are mostly achieved through specific host-guest interactions within their cavities. Electronic applications would require an effective electron transport pathway, which has been extensively studied in hybrid organic-inorganic materials with extended structures. These properties have not been considered for MOCs because cage-to-cage interactions in these materials have rarely been examined and are challenging to functionalize. We report here a previously unobserved actinide-based MOC assembled from four hexagonal-bipyramidal-coordinated uranyl ions and six bidentate flexible ligands. Remarkably, each isolated cage is further interlocked with six adjacent ones through mechanical bonds, resulting in the first case of a 0D → 3D f-element polycatenated metal-organic cage, SCU-14. Long-range π-π stacking extending throughout the structure is built via polycatenation, providing a visible carrier transmission path. SCU-14 is also an extremely rare case of an intrinsically semiconductive MOC with a wide band gap of 2.61 eV. Combined with the high X-ray attenuation efficiency, SCU-14 can effectively convert X-ray photons to electrical current signals and presents a promising sensitivity of 54.93 µC Gy-1 cm-2.

Trapped excited electrons in Ni2+-doped perovskite KZnF3 nanocrystals in KF-ZnF2-SiO2 glass ceramics: publisher's note.

This publisher's note contains a correction to Opt. Lett.45, 4984 (2020)OPLEDP0146-959210.1364/OL.402229.

Trapped excited electrons in Ni2+-doped perovskite KZnF3 nanocrystals in KF-ZnF2-SiO2 glass ceramics.

The photonic properties of glass ceramics (GCs) are often enabled by encapsulating nanocrystals (NCs) and doped transition metal ions (TMIs). However, it is difficult to probe the optics-related effect between the host NCs' band structure and doped TMIs' d-d orbitals. Herein, perovskite-type KZnF3:NiNCs in KF-ZnF2-SiO2 GCs were prepared and taken as a model system. The excited-state dynamics of host NCs and Ni ions' d-d orbitals were studied by transient absorption spectroscopy. It presents a strong interaction between Ni's d orbitals and the band edge, which could extract excitonic energy in photonic applications. These findings facilitate understanding and design of TMIs-doped GCs in real-life photonic applications.

The effects and costs of laparoscopic versus abdominal myomectomy in patients with uterine fibroids: a systematic review and meta-analysis.

BACKGROUND: Abdominal myomectomy (AM) and laparoscopic myomectomy (LM) are commonly see surgery for the uterine fibroids, several randomized controlled trials (RCTs) have compared the role of AM and LM, the results remained inconsistent. Therefore, we attempted this meta-analysis to analyze the role of LM versus AM in patients with uterine fibroids. METHODS: We searched PubMed et al. databases from inception date to July 31, 2019 for RCTs that compared LM versus AM in patients with uterine fibroids. Two authors independently screened the studies and extracted data from the published articles. Summary odd ratios(OR) or mean differences(MD) with 95% confidence intervals(CI) were calculated for each outcome by means of fixed- or random-effects model. RESULTS: Twelve RCTs with a total of 1783 patients were identified, with 887 patients for and 897 patients for AM. Compared with AM, LM could significantly decrease the blood loss (OR = - 29.78, 95% CI -57.62- - 0.95), shorten the duration of postoperative ileus (OR = - 10.91, 95% CI -18.72- - 3.11), reduce the length of hospital stay (OR = - 1.57, 95% CI -2.05- - 1.08), but LM was associated with longer duration of operation (OR = 16.10, 95% CI 6.52-25.67) and higher medical cost (OR = 17.61, 95% CI 7.34-27.88). CONCLUSIONS: LM seems to be a better choice for patients with uterine fibroids, more related studies are needed to identify the role of LM and AM for the treatment of uterine fibroids.

Ratiometric Monitoring of Thorium Contamination in Natural Water Using a Dual-Emission Luminescent Europium Organic Framework.

Traditional analytical methods of thorium contamination suffer from several disadvantages such as time-consuming procedures and an equipment-intensive nature, leading to substantial challenges in rapid and on-site monitoring of thorium concentrations in complex natural water systems. We report here the first case of a luminescent metal organic framework based probe (ThP-1) for highly sensitive and selective self-calibrated sensing of Th4+ contamination in natural fresh water media with a notably facilitated detection procedure. The detection limit of ThP-1 was determined to be 24.2 µg/L, much lower than the thorium contamination standard of 246 µg/L in drinking water defined by the World Health Organization. Importantly, the detection procedure based on the rarely reported self-calibration manner is greatly beneficial in improving the detection accuracy. The self-calibrated luminescence evolution process shows a great anti-interference ability capable of detecting thorium contamination in a wide concentration range from 24.2 µg/L to 300 mg/L, which can not be achieved directly by the traditional methods. The Th4+-selective luminescence response originates from the selective uptake and efficient enrichment of Th4+ by the host framework of ThP-1 through inner-sphere coordination, which is further confirmed by batch experiments, X-ray absorption spectroscopic study, and DFT calculations.

Comparison between Serum HE4 and CA125 as Tumor Markers in Premenopausal Women with Benign Pelvic Mass.

BACKGROUND: The aim of the study was to evaluate the role of human epididymal secretory protein (HE4), cancer antigen 125 (CA125), and the Risk of Ovarian Malignancy Algorithm (ROMA) in diagnosing benign pelvic masses in premenopausal women. METHODS: Serum was collected from 391 premenopausal women with benign pelvic mass prior to surgery and from 45 healthy individuals. Serum HE4 and CA125 levels and ROMA scores were evaluated separately. RESULTS: Among the 391 women with benign pelvic mass, 2.3% (9/391) had elevated HE4 levels (> 70 pmol/L), while 37.1% (145/391) had elevated CA125 levels (> 35 U/mL) (p < 0001). Endometriosis provided false-positive results for CA125 levels in more than half of the cases but resulted in no significant change for HE4 level. In 13 gravid women with a mass, 30.8% (4/13) and 38.5% (5/13) had elevated HE4 and CA125 levels, respectively; however, the difference was not significant (p > 0.05). Moreover, serum levels and patient percentages for CA125 elevation significantly increased with increase in mass diameter, whereas those for HE4 did not. CONCLUSIONS: CA125 elevation showed random results for benign pelvic masses, while HE4 elevation showed a higher specificity. Thus, serum HE4 testing is a better approach than CA125 testing for diagnosing benign pelvic masses in premenopausal women.

Precoding Design for Energy Efficiency Maximization in MIMO Half-Duplex Wireless Sensor Networks with SWIPT.

This paper explores the energy efficiency (EE) maximization problem in single-hop multiple-input multiple-output (MIMO) half-duplex wireless sensor networks (WSNs) with simultaneous wireless information and power transfer (SWIPT). Such an energy efficiency maximization problem is considered in two different scenarios, in which the number of energy-harvesting (EH) sensor nodes are different. In the scenario where the single energy-harvesting sensor node is applied, the modeled network consists of two multiple-antenna transceivers, of which the energy-constrained energy-harvesting sensor node harvests energy from the signals transmitted from the source by a power splitting (PS) scheme. In the scenario of multiple EH sensor nodes, K energy-constrained sensor nodes are applied and the same quantity of antennas are equiped on each of them. The optimization problem is formulated to maximize the energy efficiency by jointly designing the transceivers' precoding matrices and the PS factor of the energy-harvesting sensor node. The considered constraints are the required harvested energy, the transmission power limit and the requirement on the data rate. The joint design of the precoding matrices and the PS factor can be formulated as an optimization problem, which can be transformed into two sub-problems. An alternating algorithm based on Dinkelbach is proposed to solve the two sub-problems. The convergence of the proposed alternating algorithm, the solution optimality and the computational complexity are analyzed in the paper. Simulation results demonstrate the convergence and effectiveness of our proposed algorithm for realizing the maximum energy efficiency.