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Hollow nanoporous carbon architectures (HNCs) present significant utilitarian value for a wide variety of applications. Facile and efficient preparation of HNCs has long been pursued but still remains challenging. Herein, we for the first time demonstrate that single‐component metal–organic frameworks (MOFs) crystals, rather than the widely reported hybrid ones which necessitate tedious operations for preparation, could enable the facile and versatile syntheses of functional HNCs. By controlling the growth kinetics, the MOFs crystals (STU‐1) are readily engineered into different shapes with designated styles of crystalline inhomogeneity. A subsequent one‐step pyrolysis of these MOFs with intraparticle difference can induce a simultaneous self‐hollowing and carbonization process, thereby producing various functional HNCs including yolk‐shell polyhedrons, hollow microspheres, mesoporous architectures, and superstructures. Superior to the existing methods, this synthetic strategy relies only on the complex nature of single‐component MOFs crystals without involving tedious operations like coating, etching, or ligand exchange, making it convenient, efficient, and easy to scale up. An ultra‐stable Na‐ion battery anode is demonstrated by the HNCs with extraordinary cyclability (93 % capacity retention over 8000 cycles), highlighting a high level of functionality of the HNCs. [ABSTRACT FROM AUTHOR]

Hollow nanoporous carbon architectures (HNCs) present significant utilitarian value for a wide variety of applications. Facile and efficient preparation of HNCs has long been pursued but still remains challenging. Herein, we for the first time demonstrate that single‐component metal–organic frameworks (MOFs) crystals, rather than the widely reported hybrid ones which necessitate tedious operations for preparation, could enable the facile and versatile syntheses of functional HNCs. By controlling the growth kinetics, the MOFs crystals (STU‐1) are readily engineered into different shapes with designated styles of crystalline inhomogeneity. A subsequent one‐step pyrolysis of these MOFs with intraparticle difference can induce a simultaneous self‐hollowing and carbonization process, thereby producing various functional HNCs including yolk‐shell polyhedrons, hollow microspheres, mesoporous architectures, and superstructures. Superior to the existing methods, this synthetic strategy relies only on the complex nature of single‐component MOFs crystals without involving tedious operations like coating, etching, or ligand exchange, making it convenient, efficient, and easy to scale up. An ultra‐stable Na‐ion battery anode is demonstrated by the HNCs with extraordinary cyclability (93 % capacity retention over 8000 cycles), highlighting a high level of functionality of the HNCs. [ABSTRACT FROM AUTHOR]

The pear (Pyrus pyrifolia) is an important accessory fruit in which the pear core is tarter than the pear pulp. However, the reason for the acidic core and diversity in the taste of the same fruit is not clear. In this study, we observed that the citrate contents were three times higher in the core than in the pulp, while the malate content decreased along with fruit development and was significantly lower in the core than in the pulp at 110 days after flowering. Overall transcript levels for citrate-malate synthesis-related genes increased more in the pear core than the pulp at early fruit development, while degradation-related genes activity was nearly similar or non-significant between the core and pulp during fruit development. The lesser malate accumulation in the pear core compared to the pulp at 110 DAF was possibly due to the reduced activity of tDT2 gene. Regarding citrate accumulation, we identified five important p-type H+-ATPase genes in pear and found that the relative expression level of the PH8.1 gene was four-fold higher in the core than in the pulp during fruit development. Moreover, the expression level of di-carboxylate carrier gene 2 (DIC2) was constantly and significantly higher in the core than in the pulp. In addition, correlation analysis signified that the transcript levels of the two genes PH8.1 and DIC2 positively and significantly correlated with the citrate contents. These results suggested that the increased and collaborative activity of PH8.1 and DIC2 played a key role in the higher citrate accumulation in the core than the pulp, thus, with the help of molecular breeding tools, the citrate contents can be optimized in pear fruit for divers and improved fruit flavoring. [ABSTRACT FROM AUTHOR]

Charged metal-organic cages generally produce aggregates with various morphologies and different properties through the multiple supramolecular interactions in solution. Herein, a luminescent hexahedral metal-organic cage containing pyrene chromophores is successfully constructed through coordination-driven subcomponent self-assembly. The cage exhibits novel spontaneous aggregation in a dilute solution and time-dependent luminescence enhancement behavior during the subsequent incubation process. Dynamic light scatter (DLS) and transmission electron microscopy (TEM) results prove that the metal-organic cages can form blackberry-like aggregates in methanol dilute solution. Unexpectedly, the luminescent intensity of this system shows a linear increase with the extension of the incubation time in methanol, and this process is also reflected in the change in the quantum yield of the system (2% to over 80% after 5 days incubation time). Ultraviolet-visible (UV-vis), 1H nuclear magnetic resonance (1H NMR) and mass spectra show that metal-organic cages can stably exist in dilute solution. Time-depended DLS and TEM data reveal that the aggregates of metal-organic cages are gradually changed from the dense state to the loose one, which may involve the transition of the system from an energy unstable state to a stable one, probably leading to the unusual time-dependent luminescent property. This unique time-dependent luminescent cage aggregate can be potentially applied as a "supramolecular time meter". [ABSTRACT FROM AUTHOR]

Objective To summarize the clinical features and electrophysiological characteristics of stiff-person syndrome (SPS). Methods and Results Clinical data of 11 SPS patients [8 were classic and 3 were stiff-person plus syndrome (SPPS)], who were diagnosed and treated from August 2009 to November 2018, were retrospectively collected. They mainly presented paroxysmal muscle stiffness and pain spasm under stimulation or emotional excitement. The first affected sites were at trunk (4 cases) or limb (7 cases) muscles, and by the time of diagnosis, were mainly at truck muscles (8 cases). Anti - glutamic acid decarboxylase (GAD) antibody testing was positive in 6 cases. Electromyography (EMG) of all the patients showed continuous motor unit activity (CMUA) in the affected muscles at rest state. After treated by benzodiazepines, motor unit potential (MUP) obviously decreased or even disappeared in 6 patients. Conclusions Stiff-person syndrome is a rare autoimmune disease with multiple initial sites, atypical initial symptoms and difficulty in early diagnosis. It should be distinguished from many diseases such as familiar hyperekplexia, tetanus, myotonia congenita and multiple sclerosis (MS). [ABSTRACT FROM AUTHOR]

Objective To report the efficacy and safety of lamotrigine in the treatment of one case of Becker myotonia congenita. Methods and Results A 17 - year - old male had muscle stiffness in the limbs as the first symptom, which could be alleviated after repeated exercise. The creatine kinase (CK) level was normal. Genetic testing showed there were two missense mutations c.1205C > T (p.Ala402Val) and c.896T > C (p.Val299Ala) located in exon 11 and 8 of CLCN1 gene respectively in the proband. The missense mutation c.1205C > T (p.Ala402Val) in exon 11 was found out in his mother and c.896T > C (p. Val299Ala) located in exon 8 was found out in his father. The latter, exon 8 c.896T > C of CLCN1 gene has not been reported. The proband was clearly diagnosed as Becker myotonia congenita, and his family was diagnosed as Becker myotonia congenita pedigree. After 5 years' treatment with lamotrigine, the symptom of myotonia was significantly improved and no adverse reactions was observed. Conclusions The missense mutation in exon 8 c.896T > C in this patient further expanded the CLCN1 gene mutation spectrum. Lamotrigine is effective in treating Becker myotonia congenita, providing a new idea for the treatment of myotonia congenita. [ABSTRACT FROM AUTHOR]

Background: To quantify the contribution of locally implemented prevention programmes in contributing to reductions in treatment and care costs by averting HIV infections among those who inject drugs this study calculates net financial benefit of providing harm reduction programmes using information from services being implemented in Urumqi, Xinjiang Uighur Autonomous Region of China ( between 2005 and 2010).Methods: Information was collected to assess cost of providing methadone treatment (MMT) and needle and syringe programmes (NSP). HIV incidence was estimated among people who inject drugs (PWID). HIV infections averted were calculated. Net benefit was assessed by estimating costs of providing prevention programmes and comparing these to the costs of providing care.Results: An estimated 5678 (range 3982-7599) HIV infections were averted between 2005 and 2010 and the net financial benefit of providing harm reduction programmes compared to treatment and care costs for HIV infections averted was USD 4.383 million during the same time period.Conclusion: These results demonstrate the net and accumulating benefit of investing in harm reduction programmes for PWID in Urumqi. The return on investment progressively increased during the time period studied and it is clear that these cost savings will continue to accrue with the continued implementation of HIV prevention interventions in the community that include harm reduction programmes targeted at PWID. [ABSTRACT FROM AUTHOR]