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Developing rapid and non-invasive diagnostics for Helicobacter pylori (HP) is imperative to prevent associated diseases such as stomach gastritis, ulcers, and cancers. Owing to HP strain heterogeneity, not all HP-infected individuals incur side effects. Cytotoxin-associated gene A (CagA), and vacuolating cytotoxin A (VacA) genes predominantly drive HP pathogenicity. Therefore, diagnosing CagA and VacA genotypes could alert active infection and decide suitable therapeutics. We report an enhanced LbCas12a trans-cleavage activity with extended reporters and reductants (CEXTRAR) for early detection of HP. We demonstrate that extended ssDNA reporter acts as an excellent signal amplifier, making it a potential alternative substrate for LbCas12a collateral activity. Through a systematic investigation of various buffer components, we demonstrate that reductants improve LbCas12a trans-cleavage activity. Overall, our novel reporter and optimal buffer increased the trans-cleavage activity to an order of 16-fold, achieving picomolar sensitivity (171 pM) without target pre-amplification. Integrated with loop-mediated isothermal amplification (LAMP), CEXTRAR successfully attained attomolar sensitivity for HP detection using real-time fluorescence (43 and 96 aM), in-tube fluorescence readouts (430 and 960 aM), and lateral flow (4.3 and 9.6 aM) for CagA and VacA, respectively. We also demonstrate a rapid 2-min Triton X-100 lysis for clinical sample analysis, which could provide clinicians with actionable information for rapid diagnosis. CEXTRAR could potentially spot the

Uncoupling protein-1 (UCP1), located at the inner membrane of mitochondria, is expressed primarily in brown adipose tissue and mediates the permeability of protons through the inner mitochondrial membrane. This research examines whether human UCP1 can uncouple oxidative phosphorylation in E. coli. Recombinant human UCP1 that includes an N terminus signal peptide for the bacterial inner membrane was expressed in E. coli. Our testing showed that UCP1 functions as a proton transporter in the bacterial membrane, increasing its permeability, decrease ATP synthesis at neutral pH and reducing the viability of E. coli in markedly acidic environments. These results suggest that UCP1 can uncouple oxidative phosphorylation in E. coli. The decreased acid resistance (AR) of E. coli with UCP1 expressed in the membranes confirmed that oxidative phosphorylation plays a role in AR through the pumping of protons to regulate the intracellular pH, and demonstrate that UCP1 can be used as an uncoupler protein for bacterial metabolic research.

A new diamine monomer with a dioxinyl bipyrimidine group was synthesized. Polyimide containing a bipyrimidine group was successfully homopolymerized by chemical imidization. Analyses to determine the structure and properties of these polymers were conducted using 1H NMR and FTIR spectroscopy and gel permeation chromatography (GPC). For the first time, cobalt acetate was incorporated into the synthesized polyimide to fabricate cobalt-complexed polyimide thin film composite membranes (TFCMs) by spin coating. To fully understand the behavior of cobalt complexed TFCMs, these membranes were synthesized and then characterized by FTIR spectroscopy, X-ray diffraction (XRD), and differential scanning calorimetry (DSC) to survey the effects of cobalt acetate on polyimide. The morphologies of TFCMs were determined using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Phase separations and defects were absent in all cobalt-complexed TFCMs; the average thickness of the films ranged from 550 to 600 nm. This strongly suggested that cobalt acetate has good compatibility with bipyrimidine polyimide. The gas separation performance for TFCMs was also determined with the following results: the CO2 permeance of DMD-PI-3.0 (mixing 3.0 wt% cobalt acetate) TFCMs was 69.9 GPU at 35 °C and 1.5 bar while the selectivity of CO2/CH4 was 44.79 for DMD-PI-15 TFCMs. In short, this work reports a promising method to utilize the separation characteristics of polyimide TFCMs by incorporating cobalt ions.

To investigate the effect of the segment architecture on membrane performance, a series of micro-block-type poly(ether sulfone)s with long hydrophilic segments were synthesized. Meanwhile, two other classes of polymers with random and intermediate construction were also synthesized. After optimized chloromethylation and quaternization reactions, respectively, the resulting AEMs were obtained with comparable IEC values. TTP-n-QAPES with the longest hydrophilic segment and the most intensive ion clustering produced the most distinct hydrophilic–hydrophobic phase morphology, which was confirmed by small-angle X-ray scattering (SAXS) and atomic force microscopy (AFM) observation. TTP-18.2-QAPES with an IEC of 2.17 meq g−1 showed a hydroxide conductivity of 64.5 mS cm−1 at 80 °C, which was almost 1.34 times higher than that of a random copolymer based AEM with the same IEC value, while preserving the promoted water management capacity and dimensional stability (about 20% lower than that of random type AEMs) due to the well-defined ion nanochannels. Moreover, TTP-n-QAPES was more stable than the corresponding random type AEMs under harsh basic conditions. A systematic study of long-term alkaline stability was performed, and SN2 nucleophilic substitution could be determined as the main degradation method by 1H NMR spectroscopy. Furthermore, the TTP-18.2-QAPES based MEA achieved a considerable power density of 148 mW cm−2 at 60 °C. These results suggest that the construction of long hydrophilic segments is a promising approach to promote the comprehensive performance of AEMs.

Confined polymerization is an effective method for precise synthesis, which can further control the micro‐nano structure inside the composite material. Polyaniline (PANI)‐based composites are usually prepared by blending and original growth methods. However, due to the strong rigidity and hydrogen bonding of PANI, the content of PANI composites is low and easy to agglomerate. Here, based on confined polymerization, it is reported that polyaniline /polyether ether ketone (PANI/PEEK) film with high PANI content is synthesized in situ by a one‐step method. The micro‐nano structure of the two polymers in the confined space is further explored and it is found that PANI grows in the free volume of the PEEK chain, making the arrangement of the PEEK chain more orderly. Under the best experimental conditions, the prepared 16 µm‐PANI/PEEK film has a dielectric constant of 205.4 (dielectric loss 0.401), the 75 µm‐PANI/PEEK film has a conductivity of 3.01×10−4 S m−1. The prepared PANI/PEEK composite film can be further used as electronic packaging materials, conductive materials, and other fields, which has potential application prospects in anti‐static, electromagnetic shielding materials, corrosion resistance, and other fields., Polyaniline/polyether ether ketone (PANI/PEEK) composite film is successfully synthesized using PEEKt film as a template through confined polymerization. PANI and PEEK are co‐grown in situ by one‐step method, and the micro‐nano structure changes are further investigated. PANI/PEEK film has a significant application effect in high dielectric materials, conductive materials and other fields.

Monoculture practices in plantation forests reduce biodiversity and soil fertility compared with the adjacent patches of primary or secondary forests. Thus, it is urgent to convert monocultures into mixed stands to resolve those problems. In Northeast China, pure larch (Larix spp., mainly including L. olgensis, L. gmelinii, and L. kaempferi) plantations (LPs) are widely converted into mixed larch-walnut stands by introducing Juglans mandshurica (a native and light-demanding broadleaved tree species in secondary forests) into the LPs. However, the success of the natural regeneration of J. mandshurica must rely on rodent-mediated seed dispersal away from parental trees, and the dispersal processes are largely influenced by microhabitat changes during the thinning management of plantations. A field trial was conducted by releasing tagged J. mandshurica seeds in LPs with three thinning intensities (0%, 25%, and 50% thinning intensities) during two continuous growing seasons. The results indicated that among the three thinning treatments, the removal rate of seeds by rodents was the fastest, and the scatter-hoard seed (6.3 m) was most plentiful, in the 25% thinning intensity of LPs. On the contrary, the seed dispersal rate was the slowest, and the seed dispersal distance (8.3 m) was the farthest, in the stand with 50% thinning intensity in the non-mast year of 2015. This finding may be because both the changes in canopy openness and variations in microhabitats (including light incidence, soil moisture, and coverage of understory shrubs and herbs) caused by different thinning intensities have a synergetic effect on rodent-mediated seed dispersal. Inter-annual variation in seed production resulted in faster removal rates with larger cache proportion in LPs (25.93%) and shorter dispersal distance (6.4 m) in the non-mast year (2015) and vice versa in the mast year (2016). Thinning is a potentially feasible practice to promote rodent-mediated seed dispersal and the potential seed germination of J. mandshurica in LPs. We could take varying measures for different silviculture objectives to make full use of the thinning advantage in rodent-mediated seed dispersal; for instance, 25% thinning intensity (437–532 trees ha−1) provided a suitable microhabitat for rodents to disperse walnut seeds into LPs faster, and 50% thinning intensity (292–355 trees ha−1) is suggested in LPs to promote rodents to cache seeds with longer distance.

It is increasingly important to build topic linkages between scientific publications and patents for the purpose of understanding the relationships between science and technology. Previous studies ...

In this paper, a kind of complex fuzzy linear matrix equation A X ˜ B = C ˜ , in which C ˜ is a complex fuzzy matrix and A and B are crisp matrices, is investigated by using a matrix method. The complex fuzzy matrix equation is extended into a crisp system of matrix equations by means of arithmetic operations of fuzzy numbers. Two brand new and simplified procedures for solving the original fuzzy equation are proposed and the correspondingly sufficient condition for strong fuzzy solution are analysed. Some examples are calculated in detail to illustrate our proposed method.

Matrices as mathematical models have been used in each branch of scientific fields for hundred years. We propose a new type of matrices, called topological coding matrices (Topcode-matrices). Topcode-matrices show us the following advantages: Topcode-matrices can be saved in computer easily and run quickly in computation; since a Topcode-matrix corresponds two or more Topsnut-gpws, so Topcode-matrices can be used to encrypt networks such that the encrypted networks have higher security; Topcode-matrices can be investigated and applied by people worked in more domains; Topcode-matrices can help us to form new operations, new parameters and new topics of graph theory, such as vertex/edge splitting operations and connectivities of graphs. Several properties and applications on Topcode-matrices, and particular Topcode-matrices, as well as unknown problems are introduced.

Since most of Chinese people use their mother tongue in everyday life, so we try to use Chinese characters for producing Topsnut-gpws (the abbreviation of passwords made by "topological structure plus mathematical restriction"), such Topsnut-gpws are called Hanzi-gpws in this article. Our Hanzi-gpws can to: (i) help Chinese people to remember their passwords written in Chinese; (ii) make easily text-based passwords (Hanzi-TB-paws); (iii) join information security with Chinese characters together. We, for producing Hanzi-TB-paws, introduce a technique based on hand-writing strokes of Chinese characters. Other techniques of making Hanzi-TB-paws are Topsnut-matrices and Hanzi-GB2312-80 matrices. Moreover, we generalize graph labellings to Hanzi-labellings with domination of Chinese words, phrases and idioms, even essays, poems, novels, proses, reports, news written in Chinese. Some problems are proposed in the end of this paper.

The long-term stressful utilization of forests and grasslands has led to ecosystem degradation and C loss. Since the late 1970s China has launched six key national ecological restoration projects to protect its environment and restore degraded ecosystems. Here, we conducted a large-scale field investigation and a literature survey of biomass and soil C in China's forest, shrubland, and grassland ecosystems across the regions where the six projects were implemented (∼16% of the country's land area). We investigated the changes in the C stocks of these ecosystems to evaluate the contributions of the projects to the country's C sink between 2001 and 2010. Over this decade, we estimated that the total annual C sink in the project region was 132 Tg C per y (1 Tg = 1012 g), over half of which (74 Tg C per y, 56%) was attributed to the implementation of the projects. Our results demonstrate that these restoration projects have substantially contributed to CO2 mitigation in China.

Background and purpose Increasing energy expenditure through adipocyte thermogenesis is generally accepted as a promising strategy to mitigate obesity and its related diseases. However, few clinically effective and safe agents are known to promote adipocyte thermogenesis. In this study, 20 traditional Chinese herbal medicines were screened to examine whether they induced adipocyte thermogenesis. Experimental approach The effects of Chinese herbal medicines or components isolated from extracts of A. membranaceus, on adipocyte thermogenesis were analysed by assessing expression of uncoupling protein 1 (UCP1) by qPCR. Eight-week-old C57BL6/J male mice were fed a high-fat diet for 8 weeks and then randomized to two groups treated with vehicle or formononetin for another 8 weeks. Glucose tolerance tests and staining of adipose tissue with haematoxylin and eosin were carried out. Whole-body oxygen consumption was measured with an open-circuit indirect calorimetry system. Key results Extracts of A. membranaceus increased expression of Ucp1 in primary cultures of mouse adipocytes. Formononetin was the only known component of A. membranaceus extracts to increase adipocyte Ucp1 expression. Diet-induced obese mice treated with formononetin gained less weight and showed higher energy expenditure than untreated mice. In addition, formononetin binds directly with PPARγ. Conclusions and implication Taken together, our study demonstrates that the Chinese herbal medicine from A. membranaceus and its constituent formononetin have the potential to reduce obesity and associated metabolic disorders. Our results suggest that formononetin regulates adipocyte thermogenesis as a non-classical PPARγ agonist.

The separation of organic solvents can be improved in a sustainable way by implementing membranes produced via streamlined processing. However, conventional membranes are not typically used in organic solvents, and thus require further chemical cross-linking before use. This process is complicated, and cross-linking agents are harmful to the environment. This study investigated the synthesis of a sulfonated poly(aryl ether ketone) (SPAEK) copolymer with a controlled degree of sulfonation via molecular design as a novel nanofiltration membrane in organic solvent. The introduction of a suitable number of sulfonic acid groups improved the hydrophilicity and surface charge of the membrane compared to conventional poly(aryl ether ketone) (PAEK), leading to excellent performance in separating alcoholic solvents and negatively charged dyes. The membrane still exhibited good separation performance, and no obvious damage to its microstructure was found by FESEM after the membrane was soaked in N,N-dimethylformamide (DMF) for 7 days. Consequently, the ethanol permeance and dye rejection of the membrane was maintained. PEK-SPEDEK membrane has potential applications in OSN under complex and harsh conditions such as printing, dyeing and pharmaceuticals.

Larch (Larix spp.) is planted extensively after clear-cut of secondary forests in Northeast China to satisfy the enormous timber demands. However, some serious problems arise in larch plantations (LPs) due to mono-species composition, such as a decline in soil fertility and acidification of surface runoff. Converting pure LPs into larch-broadleaf mixed forests would resolve these issues. Since larch-walnut mixed forests are mutually beneficial, it is crucial to promote the regeneration of Juglans mandshurica in LPs. Rodent-mediated seed dispersal of J. mandshurica determines the regeneration success or failure and is closely related to stand structure. Forest gaps are formed by an uneven thinning that changes stand structure in plantation management; the gap size and within-gap position are two key characteristics that affect tree regeneration by changing the micro-environment. We hypothesized that rodent-mediated walnut seed dispersal were strongly influenced by these two key factors. The field trial was conducted by releasing tagged J. mandshurica seeds in two sizes of artificial gaps in LPs (small and medium gaps) and at four positions (south, north, east and west) of the gap edges. The seed releases were conducted at three stages of seed rain (early, middle and final stages) during two continuous growing seasons. Our results showed that only the seed removal rate was significantly affected by gap size and within-gap position; the rate in medium gaps was significantly higher than that in small gaps (Wald = 24.57, df = 1, P

The development of Internet information technology has been advancing by leaps and bounds, which marks the entry of human society into the network. The increasingly networked human society needs to understand the network structure. We study and explore the self-similar networks, and show self-similar networks of Chinese characters (called self-similar Hanzi-networks) and some conclusions on them. Self-similar Hanzi-networks can be used to produce topological graphic passwords, which are easy to derive text-based passwords.

Graphical passwords are convenient for mobile equipment with touch screen. QR code is a successful example of graphical passwords. In this paper, we design a new-type of graphical passwords, called Hanzi-gpw, which are the abbreviation of Hanzi graphical passwords, that can be use conveniently and have higher level security in information networks by mean of topological structures and colorings/labellings of graph theory. Hanzi-gpw can be saved in computer by classical matrices and run quickly than the existing graphical passwords. In the course of our research Chinese Characters, we find a new-type of graph labellings called flawed graceful labelling, so we can keep their disconnected property. Our result can be provided two or more users and to meet the needs of special populations. The methods can easily be converted into polynomial time algorithms.

Nowadays, PEEK, as a kind of high performance polymer characterized with high strength, great corrosion resistance and thermal stability is regarded as a promising membrane material. In this study, PEEK fibers were prepared by melt spinning and then woven into textiles. Furthermore, interface reduction was utilized to give a more hydrophilic textile (PEEK-OH textile). In addition, considering to make full use of the huge membrane pores of the textile, a liquid-infused method was employed to regulate its surface energy and to establish an under-water oleophobic surface. Surprisingly, PEEK-OH textile functioned in not only oil/water separation, but also separating immiscible organic liquids with different polarities just through a liquid-infused approach. More importantly, we firstly introduced ‘mediator effect’ during the pre-wetting process before separation, taking ethanol as a ‘mediator’. Furthermore, according to the ‘mediator effect’, an under-oil hydrophobic membrane was established using dichloromethane as a ‘mediator’. As we expected, both PEEK and PEEK-OH textiles revealed features such as high flux, admirable selectivity, competitive strength, great corrosion resistance and thermal stability, herein, they promised to be used for oil/water separation in practical environment.

In Northeast China, larch (Larix spp.) plantations exchanged from broadleaved secondary forests to meet the demand of timber consumption are facing some serious problems, including soil fertility decline, acidification of surface runoff and low levels of biodiversity. How to promote the regeneration of broadleaved tree species in larch plantations and convert the pure larch plantations into mixed larch-broadleaved forests would be a top priority to solve some of these issues. The success of this conversion mainly depends on the seedling performances of the selected broadleaved tree species. Seedlings of four dominant broadleaved tree species (intermediate shade tolerant species: Fraxinus mandshurica and Acer mono, shade intolerant species: Juglans mandshurica and Quercus mongolica) from the secondary forests were planted in the thinned pure larch stands (0%, 25%, 50% and 100% thinning) to explore the adaptive strategies (biomass accumulation, leaf structural, nutrient and physiological traits) of two shade-tolerant types of broadleaved tree species responding to the thinning in larch plantations. We found that compared with the intermediate shade tolerant group, the shade intolerant species had higher leaf construction cost (CC), carbon:phosphorus (C:P) ratio, nitrogen:phosphorus (N:P) ratio, and nonstructural carbohydrate concentration (NSC) in stems and roots at all thinning treatments, and had higher leaf ash and specific leaf area (SLA) only in the larch plantations with a canopy openness more than 25 ± 1% (i.e., the 50% and 100% thinning intensity). Across all the thinning treatments, higher survival rates were found for the shade intolerant species relative to the intermediate shade tolerant species, but relative height growth (RHG) did not differ significantly between the groups. When the canopy openness of larch plantations was less than 21% (i.e., 0% and 25% thinning intensity), the intermediate shade tolerant group could utilize essential growth resources more efficiently by investing less energy per unit of RHG, and had a greater photosynthetic capacity at minimal costs relative to the shade intolerant species. However, regression analyses indicated that across all the thinning treatments (and hence all the light irradiance in this study), at a given NSC, there was a higher RHG for the shade intolerant group; also at a common SLA, there were a lower CC and lower area-based N for the shade intolerant group. Ordination using 15 eco-physiological and chemical traits of plants indicated that the major axis of shade intolerant-intermediate shade tolerant dichotomy was primarily driven by leaf NSC, CC and C:P ratio, and was significantly linked with RHG. These results demonstrated that it is a potentially feasible practice for building uneven-aged larch-broadleaved mixed forests by thinning and planting seedlings of native broadleaved tree species in pure larch plantations. Furthermore, the regeneration of the intermediate shade tolerant group and the shade intolerant species could be promoted in larch plantations with the canopy openness less than 21% and more than 25%, respectively. This study may provide an insight into uneven-aged and mixed silviculture for larch plantation forests.

The mixed-broadleaved Korean pine ( Pinus koraiensis Sieb. et Zucc.) forest (MBKPF) is a zonal climax ranging from Northeast China to the Far East region of Russia. However, since the 1950s, most of the MBKPFs in Northeast China have become the mixed broadleaved secondary forests due to the heavy forest exploitation by timber harvesting. The natural regeneration of Korean pine is generally poor because of the light limitation in Northeast China. This study was conducted to understand how Korean pine seedlings adapt to different canopy openness (CO) and what would be the minimum CO for its establishment and growth in the natural forest stands. In order to test the hypothesis that Korean pine seedlings have acclimated to low light regimes, the responses of photosynthetic, morphological and growth parameters to light environments were examined in Korean pine seedlings that were field-grown in secondary forests. The results can provide the references for the restoration of MBKPFs in Northeast China. Three-year-old Korean pine seedlings were under-planted in secondary forest stands with three levels of CO at 30%, 15% and 7%, which were created by modifying the branches of the secondary forest stands. After one year of acclimation under the secondary forest stands, the variations in the physiological and morphological characteristics of the needles as well as the growth parameters were measured. The maximum net photosynthesis ( A max ), dark respiration ( R d ), needle chlorophyll (Chl) contents and total needle nitrogen (N) contents all responded positively to the increased CO. The total non-structural carbohydrate (TNC), A max , R d , and N contents in the 7% stand were significantly lower than those in the 15% and 30% stands ( p F v ′/ F m ′) in the 7% stand was the lowest and was significantly different from those in the 15% and 30% stands ( p p > 0.05). These results indicated that 7% CO seedlings were experiencing some degree of low light stress. The leaf mass area (LMA) and height growth decreased as the CO decreased from 30% to 15% to 7%, while the lateral shoot growth increased. Therefore, needle morphology, tree height and crown growth of Korean pine seedlings displayed a large plasticity in response to variations in light intensities. These findings suggest that Korean pine seedlings can strongly acclimate in the forest canopy by adjusting physiological traits that are associated with light energy distribution in the PSII and by adjusting the morphological features of their needles. These results suggest that the minimum canopy openness required for the survival of P. koraiensis seedlings (4 years old) grown under a canopy should be more than 7%.