Ultra-High Proportion of Grain Boundaries in Zinc Metal Anode Spontaneously Inhibiting Dendrites Growth.

Aqueous Zn-ion batteries are an attractive electrochemical energy storage solution for their budget and safe properties. However, dendrites and uncontrolled side reactions in anodes detract the cycle life and energy density of the batteries. Grain boundaries in metals are generally considered as the source of the above problems but we present a diverse result. This study introduces an ultra-high proportion of grain boundaries on zinc electrodes through femtosecond laser bombardment to enhance stability of zinc metal/electrolyte interface. The ultra-high proportion of grain boundaries promotes the homogenization of zinc growth potential, to achieve uniform nucleation and growth, thereby suppressing dendrite formation. Additionally, the abundant active sites mitigate the side reactions during the electrochemical process. Consequently, the 15 µm Fs-Zn||MnO2 pouch cell achieves an energy density of 249.4 Wh kg-1 and operates for over 60 cycles at a depth-of-discharge of 23 %. The recognition of the favorable influence exerted by UP-GBs paves a new way for other metal batteries.

Temperature-Tuning Desorption Ionization for Ambient Mass Spectrometry.

In the past decade, mass spectrometry (MS) has been widely used for a broad range of on-site applications. This is largely attributed to the rapid advancement of technologies, such as ambient ionization and mass spectrometer miniaturization. Here, we report the development of the temperature-tuning desorption ionization (TTDI) method for versatile on-site applications using a miniature MS system. A unique feature of TTDI is its dynamic temperature range applicable from 30 to 800 °C, which enables optimal desorption ionization applied for chemical and biological compounds through tuning the temperature at the sampling spot. The versatility of TTDI has been demonstrated through on-site MS analysis of a variety of samples, such as explosives on surfaces, drugs of abuse in biofluids, and screening biomarkers in tissues.

Overloaded axial stress activates the Wnt/ß-Catenin pathway in nucleus pulposus cells of adult degenerative scoliosis combined with intervertebral disc degeneration.

BACKGROUND: Intervertebral disc degeneration (IVDD) is the initiating factor of adult degenerative scoliosis (ADS), and ADS further accelerates IVDD, creating a vicious cycle. Nevertheless, the role of the Wnt/ß-Catenin pathway in ADS combined with IVDD (ADS-IVDD) remains a mystery. Accordingly, this study was proposed to investigate the effect of axial stress on the Wnt/ß-Catenin pathway in nucleus pulposus cells (NPCs) isolated from DS-IVDD patients. METHODS: Normal NPCs (N-NPC) were purchased and the NPCs of young (25-30 years; Y-NPC) and old (65-70 years; O-NPC) from ADS-IVDD patients were primary cultured. After treatment of NPC with overloaded axial pressure, CCK-8 and Annexin V-FITC kits were applied for detecting proliferation and apoptosis of N-NPC, Y-NPC and O-NPC, and western blotting was performed to assess the expression of Wnt 3a, ß-Catenin, NPC markers and apoptosis markers (Bax, Bcl2 and Caspase 3). RESULTS: N-NPC, Y-NPC and O-NPC were mainly oval, polygonal and spindle-shaped with pseudopods, and the cell morphology tended to be flattened with age. N-NPC, Y-NPC and O-NPC were capable of synthesizing proteoglycans and expressing the NPC markers (Collagen II and Aggrecan). Notably, the expression of Wnt 3a, ß-Catenin, Collagen II and Aggrecan was reduced in N-NPC, Y-NPC and O-NPC in that order. After overload axial stress treatment, cell viability of N-NPC and Y-NPC was significantly reduced, and the percentage of apoptosis and expression of Wnt 3a and ß-Catenin were significantly increased. CONCLUSIONS: Overloaded axial pressure activates the Wnt/ß-Catenin pathway to suppress proliferation and facilitate apoptosis of NPC in ADS-IVDD patients.

Polyol Solvation Effect on Tuning the Universal Growth of Binary Metal Oxide Nanodots@Graphene Oxide Heterostructures for Electrochemical Applications.

Tuning the uniformity and size of binary metal oxide nanodots on graphene oxide (BMO NDs@GO) is significant but full of challenges in wet-chemistry, owing to the difficulties of controlling the complicated cation/anion co-adsorption, heterogeneous nucleation, and overgrowth processes. Herein, the aim is to tune these processes by understanding the functions of various alcohol solvents for NDs growth on GO. It is found that the polyol solvation effect is beneficial for obtaining highly uniform BMO NDs@GO. Polyol shell capped metal ions exhibit stronger hydrogen-bond interactions with the GO surface, leading to a uniform cation/anion co-adsorption and followed heterogeneous nucleation. The polyol-solvated ions with large diffusion energy barrier drastically limit the ion diffusion kinetics in liquids and at the solid/liquid interface, resulting in a slow and controllable growth. Moreover, the synthesis in polyol systems is highly controllable and universal, thus eleven BMO and polynary metal oxide NDs@GO are obtained by this method. The synthetic strategy provides improved prospects for the manufacture of inorganic NDs and their expanding electrochemical applications.

[Therapeutic effects of different doses of botulinum toxin A injection on tiptoe deformation in children with cerebral palsy].

OBJECTIVE: To study the therapeutic effects of different doses of botulinum toxin A (BTX-A) injection on tiptoe deformation in children with cerebral palsy. METHODS: A total of 256 children with tiptoe deformation due to spastic cerebral palsy were classified into group A (muscle tension levels I-II, n=147) and group B (muscle tension levels III-IV, n=109). Group A was randomly divided into group A1 (injected with high-dose BTX-A, n=73) and group A2 (injected with low-dose BTX-A, n=74). Group B was randomly divided into group B1 (injected with high-dose BTX-A, n=55) and group B2 ( injected with low-dose BTX-A, n=54). The dose of BTX-A was 6 U/kg for groups A1 and B1 and was 3 U/kg for groups A2 and B2. Before the injection and at 1,2,6, and 12 months after injection, the muscle tension of limbs was evaluated with the modified Ashworth Scale, and the recovery of motor function of lower limbs was assessed with the Gross Motor Function Measure (GMFM). RESULTS: Before and after treatment, there were no significant differences in Ashworth and GMFM scores between groups A1 and A2 (P>0.05). After treatment, group B1 had a significantly reduced Ashworth score and a significantly increased GMFM score, and group B1 had a significantly lower Ashworth score and a significantly higher GMFM score compared with group B2 (P<0.05). For groups A and B, Ashworth score gradually declined post-treatment, reached the lowest point at 3 months after treatment, and returned to the level before treatment at 12 months after treatment; GMFM score gradually increased post-treatment and reached the peak level at 12 months after treatment (P<0.05). CONCLUSIONS: The level of muscle tension should be considered when BTX-A injection is used for treating tiptoe deformation in children with cerebral palsy. It makes no difference to use high- or low-dose BTX-A when the muscle tension level is within I-II, but high-dose BTX-A has a better performance in reducing muscle tension and improving motor function when the muscle tension level is within III-IV.

Age-different BMSCs-derived exosomes accelerate tendon-bone interface healing in rotator cuff tears model.

BACKGROUND: Rotator cuff tears (RCTs) are culprit of shoulder pain and dysfunction. Tendon-bone interface (TBI) mal-healing is an essential contributor to retear after RCTs. Consequently, present project was conducted to investigate the role of bone marrow mesenchymal stem cells (BMSCs)-derived exosomes on TBI healing. METHOD: Young BMSCs (Y-BMSCs) and Aged BMSCs (A-BMSCs) were isolated from Young (3-month-old) and old (24-month-old) SD rats, and their-derived exosomes (A-BMSCs-exo and Y-BMSCs-exo) were identified. RCTs model was established, and A-BMSCs-exo and Y-BMSCs-exo were injected at the rotator cuff using hydrogel as a vehicle. Pathological changes of TBI were observed by HE, Sirius Red and Oil Red O staining. Western blotting and RT-qPCR were applied to assess the expression of extracellular matrix (ECM)-, tendon cell (TCs)-, osteogenic-, tendon-derived stem cell (TDSCs)- and angiogenic-associated proteins and mRNAs in TBI. RESULT: Y-BMSCs exhibited increased activity, osteogenic and lipogenic abilities than A-BMSCs. After A-BMSCs-exo and Y-BMSCs-exo treatment, TBI displayed massive sharpey's fibers growing along the tendon longitudinally, and a collagen fiber-chondrocyte migration zone forming a typical tendon-noncalcified fibrocartilage-calcified fibrocartilage-bone structure. A-BMSCs-exo and Y-BMSCs-exo significantly upregulated the expression of collagen Col I/II/III, Aggrecan, TNMD, SCX, Runx2, OPN, CD45, Sox2, CD31 and VEGFR2 in TBI. In vitro, A-BMSCs-exo and Y-BMSCs-exo significantly enhanced the activity of TCs and TDSCs, TDSCs stemness, and reduced the osteogenic and lipogenic capacity of TDSCs. The effect of Y-BMSCs-exo was significantly stronger than that of A-BMSCs-exo. CONCLUSION: BMSCs-derived exosomes facilitate ECM remodeling, osteogenic differentiation, angiogenesis, and stemness of TDSCs, thereby accelerating TBI healing in RCTs, with better outcomes using young individual-derived BMSCs.

Development and biomechanical analysis of an axially controlled compression spinal rod for lumbar spondylolysis.

BACKGROUND: To elucidate the differences in mechanical performance between a novel axially controlled compression spinal rod (ACCSR) for lumbar spondylolysis (LS) and the common spinal rod (CSR). METHODS: A total of 36 ACCSRs and 36 CSRs from the same batch were used in this study, each with a diameter of 6.0 mm. Biomechanical tests were carried out on spinal rods for the ACCSR group and on pedicle screw-rod internal fixation systems for the CSR group. The spinal rod tests were conducted following the guidelines outlined in the American Society for Testing and Materials (ASTM) F 2193, while the pedicle screw-rod internal fixation system tests adhered to ASTM F 1798-97 standards. RESULTS: The stiffness of ACCSR and CSR was 1559.15 ±â€…50.15 and 3788.86 ±â€…156.45 N/mm (P < .001). ACCSR's yield load was 1345.73 (1297.90-1359.97) N, whereas CSR's was 4046.83 (3805.8-4072.53) N (P = .002). ACCSR's load in the 2.5 millionth cycle of the fatigue four-point bending test was 320 N. The axial gripping capacity of ACCSR and CSR was 1632.53 ±â€…165.64 and 1273.62 ±â€…205.63 N (P = .004). ACCSR's torsional gripping capacity was 3.45 (3.23-3.47) Nm, while CSR's was 3.27 (3.07-3.59) Nm (P = .654). The stiffness of the pedicle screws of the ACCSR and CSR group was 783.83 (775.67-798.94) and 773.14 (758.70-783.62) N/mm (P = .085). The yield loads on the pedicle screws of the ACCSR and CSR group was 1345.73 (1297.90-1359.97) and 4046.83 (3805.8-4072.53) N (P = .099). CONCLUSION: Although ACCSR exhibited lower yield load, stiffness, and fatigue resistance compared to CSR, it demonstrated significantly higher axial gripping capacity and met the stress requirement of the human isthmus. Consequently, ACCSR presents a promising alternative to CSR for LS remediation.

Genetic Testing for Global Developmental Delay in Early Childhood.

Importance: Global developmental delay (GDD) is characterized by a complex etiology, diverse phenotypes, and high individual heterogeneity, presenting challenges for early clinical etiologic diagnosis. Cognitive impairment is the core symptom, and despite the pivotal role of genetic factors in GDD development, the understanding of them remains limited. Objectives: To assess the utility of genetic detection in patients with GDD and to examine the potential molecular pathogenesis of GDD to identify targets for early intervention. Design, Setting, and Participants: This multicenter, prospective cohort study enrolled patients aged 12 to 60 months with GDD from 6 centers in China from July 4, 2020, to August 31, 2023. Participants underwent trio whole exome sequencing (trio-WES) coupled with copy number variation sequencing (CNV-seq). Bioinformatics analysis was used to unravel pathogenesis and identify therapeutic targets. Main Outcomes and Measures: The main outcomes of this study involved enhancing the rate of positive genetic diagnosis for GDD, broadening the scope of genetic testing indications, and investigating the underlying pathogenesis. The classification of children into levels of cognitive impairment was based on the developmental quotient assessed using the Gesell scale. Results: The study encompassed 434 patients with GDD (262 [60%] male; mean [SD] age, 25.75 [13.24] months) with diverse degrees of cognitive impairment: mild (98 [23%]), moderate (141 [32%]), severe (122 [28%]), and profound (73 [17%]). The combined use of trio-WES and CNV-seq resulted in a 61% positive detection rate. Craniofacial abnormalities (odds ratio [OR], 2.27; 95% CI, 1.45-3.56), moderate or severe cognitive impairment (OR, 1.69; 95% CI, 1.05-2.70), and age between 12 and 24 months (OR, 1.57; 95% CI, 1.05-2.35) were associated with a higher risk of carrying genetic variants. Additionally, bioinformatics analysis suggested that genetic variants may induce alterations in brain development and function, which may give rise to cognitive impairment. Moreover, an association was found between the dopaminergic pathway and cognitive impairment. Conclusions and Relevance: In this cohort study of patients with GDD, combining trio-WES with CNV-seq was a demonstrable, instrumental strategy for advancing the diagnosis of GDD. The close association among genetic variations, brain development, and clinical phenotypes contributed valuable insights into the pathogenesis of GDD. Notably, the dopaminergic pathway emerged as a promising focal point for potential targets in future precision medical interventions for GDD.

Different impulse control disorder evolution patterns and white matter microstructural damage in the progression of Parkinson's disease.

Background: The course of impulse control disorders (ICD) varies in the early stage of Parkinson's disease (PD). Aim: We aimed to delineate the association between the evolution pattern of ICD and the progression of PD. Methods: A total of 321 de novo PD patients from the Parkinson's Progression Markers Initiative database were included. Patients were followed up for a mean of 6.8 years and were classified into different groups according to the evolution patterns of ICD. Disease progression was compared among groups using survival analysis, in which the endpoint was defined as progression to Hoehn and Yahr stage 3 or higher for motor progression and progression to mild cognitive impairment for cognitive decline. In the fourth year of follow-up, four types of ICD evolution patterns were identified: (1) non-ICD-stable (68.2%), a patient who is consistently free of ICD; (2) late-ICD (14.6%), ICD developed during the follow-up of patients; (3) ICD-stable (11.5%), patients showed persistent ICD; and (4) ICD-reversion (5.6%), baseline ICD disappeared during the follow-up of patients with ICD. Results: The ICD-reversion type shows daily life non-motor symptoms [Movement Disorder Society-Unified Parkinson Disease Rating Scale (MDS-UPDRS) part I], daily life motor symptoms (MDS-UPDRS part II), rapid eye movement sleep behavior disorder, and anxiety symptoms has a greater impact. PD patients with different ICD evolution patterns had different changes in white matter microstructure at the onset of the disease. Those relevant brain regions are involved in ICD and non-motor functions. Conclusion: Four early ICD evolution patterns are identified in de novo PD, with different prognoses and brain white matter microstructural damage patterns, and they may predict motor progression and cognitive decline in PD patients.

A narrative review of the progress in the treatment of knee osteoarthritis.

Background and Objective: The pathogenesis of osteoarthritis (OA) involves a variety of complex mechanisms, including genetic, mechanical, metabolic, and inflammatory factors. There is evidence that inflammatory factors, abnormal chondrocyte apoptosis, and extracellular matrix degradation are closely associated with the occurrence and development of OA. The best treatment for OA is still controversial, but intra-articular injection is safer and more effective than non-surgical treatments, such as physical therapy and oral analgesics. This study sought to explore the mechanism, benefits, and adverse reactions of commonly used intra-articular injection therapy in the treatment of knee osteoarthritis (KOA). Methods: We analyzed the safety and adverse reactions of intra-articular injection in patients with KOA, and summarized the results. Key Content and Findings: Six weeks of the corticosteroid injection contributed to improve the symptoms of OA patients in short time. However, their symptoms did not improve significantly after this period. Using corticosteroids for a long time may result in oxidative stress, leading to adverse reactions, such as cartilage toxicity, and accelerate the progress of OA. Due to its high frequency, the local injection of hyaluronic acid can result in more adverse reactions when compared with the corticosteroids. Due to the lack of standardized factors for platelet-rich plasma (PRP) preparation, leukocyte-rich or leukocyte-free variants may be produced. Adverse reactions include injection-site pain, joint stiffness. Conclusions: Thus, it is necessary to promote further clinical trials to promote the clinical application of PRP.

Does a home-based exercise program play any role in the treatment of knee osteoarthritis? A meta-analysis.

BACKGROUND: Knee-osteoarthritis is a very common joint disorder, affecting about 85% of the population worldwide. The effectiveness of home-based exercises is still debatable, with many studies indicating positive outcomes with few side effects, while others find them of limited utility. OBJECTIVES: To assess the role of home-based exercise (HBE) programs in the treatment of knee osteoarthritis. MATERIAL AND METHODS: Randomized controlled trials were included as per the predefined Population, Intervention, Comparison, Outcomes and Study (PICOS) criteria. Demographic summaries and event data for osteoarthritis therapy in the exercise and control groups were assessed, and comparative efficacy was evaluated using clustered graphs. The RevMan software was used to calculate the odds ratio (OR) and risk ratio of the included studies. The risk of bias was also evaluated and heterogeneity analysis was performed. RESULTS: Fifteen clinical trials performed from 2000 to 2022, with a total of 2922 osteoarthritis patients, were included in the study, according to the chosen inclusion criteria. We observed a reduction in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores but a more marked improvement in clinical symptoms in the exercise group. The Knee Injury and Osteoarthritis Outcome Score (KOOS) increased only in the exercise group and not in the control group. We obtained a pooled OR of 0.59 (95% confidence interval (95% CI): 0.36-0.98), T2 value of 0.88, χ2 value of 185.41, degrees of freedom (df) value of 14, I2 value of 92%, and p-value <0.00001. The overall Z effect was 2.04 with a p-value of 0.04. The pooled risk ratio was 0.81 (95% CI: 0.66-0.99) with a T2 value of 0.14, χ2 value of 191.53, df value of 14, I2 value of 93%, and p-value <0.00001. CONCLUSION: The data from the studies included in this meta-analysis are in favor of the use of HBEs for the treatment of knee osteoarthritis.

One-pot hydrothermal preparation of manganese-doped carbon microspheres for effective deep removal of hexavalent chromium from wastewater.

Mn-doped activated carbon microspheres (MnOx/ACS) with super-high adsorption capacities and deep removal capability for hexavalent chromium (Cr(VI)) were successfully prepared via an ammonium persulfate-assisted hydrothermal method followed by potassium oxalate activation using KMnO4 and sucrose as raw materials. Their -physical and chemical properties, as well as those of Mn-doped non-activated carbon spheres (MnOx/CS), were characterized by XRD, SEM, TEM, EDS-mapping, XPS, N2 adsorption-desorption, ICP-AES, and elemental analysis. It was found that the manganese oxide (MnOx) particles were uniformly embedded within the carbon spheres via layer-by-layer capture, and the MnOx/ACS exhibited strong redox activity because of the multivalent nature of MnOx, resulting in excellent adsorption performance via reduction. In particular, MnOx/ACS-4 with a Mn content of 1.06 wt% and a specific surface area of 1405.7 m2 g-1 achieved a maximum adsorption capacity of 660.7 mg g-1; this can reduce Cr(VI) content to less than 0.05 mg L-1, which meets the corresponding Chinese drinking water quality standard when the initial concentration of Cr(VI) is less than 400 mg L-1. Furthermore, this highly efficient method can be extended to prepare V-, Mo-, or W-doped carbon microspheres with significantly enhanced adsorption performance for Cr(VI) compared to bare activated carbon sphere, indicating their good application prospect for the deep removal for heavy metal ions from wastewater.

Maintenance of Postharvest Quality and Reactive Oxygen Species Homeostasis of Pitaya Fruit by Essential Oil p-Anisaldehyde Treatment.

The performance of p-Anisaldehyde (PAA) for preserving pitaya fruit quality and the underpinning regulatory mechanism were investigated in this study. Results showed that PAA treatment significantly reduced fruit decay, weight loss and loss of firmness, and maintained higher content of total soluble solids, betacyanins, betaxanthins, total phenolics and flavonoids in postharvest pitaya fruits. Compared with control, the increase in hydrogen peroxide (H2O2) content and superoxide anion (O2•-) production was inhibited in fruit treated with PAA. Meanwhile, PAA significantly improved the activity of antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT). Moreover, PAA-treated pitaya fruit maintained higher ascorbic acid (AsA) and reduced-glutathione (GSH) content but lower dehydroascorbate (DHA) and oxidized glutathione (GSSG) content, thus sustaining higher ratio of AsA/DHA and GSH/GSSG. In addition, activities of ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate reductase (MDHAR) and dehydrogenation ascorbic acid reductase (DHAR), as well as the expression of HpSOD, HpPOD, HpCAT, HpAPX, HpGR, HpDHAR and HpMDHAR, were enhanced after PAA treatment. The findings suggest that postharvest application of PAA may be a reliable method to control postharvest decay and preserve quality of harvested pitaya fruit by enhancing the antioxidant potential of the AsA-GSH cycle and activating an antioxidant defense system to alleviate reactive oxygen species (ROS) accumulation.

Dose reduction with adaptive bolus chasing computed tomography angiography.

Computed Tomography (CT) has become an effective diagnosis and evaluating tool in clinical; however, its radiation exposure has drawn great attention as more and more CT scans are performed every year. How to reduce the radiation dose and meanwhile keep the resultant CT images diagnosable becomes an important research topic. In this paper, we propose a dose reduction approach along with the adaptive bolus chasing CT Angiography (CTA) techniques, which are capable of tracking the contrast bolus peak over all the blood vessel segments during the CTA scan. By modulating the tube current (and collimator width) online, we can reduce the total radiation dose and maintain the contrast to noise ratio (CNR) of the blood vessel. Numerical experiments on reference DSA data sets show that by using the proposed dose reduction method, the effective radiation dose can be saved about 39%.

Identification of a Modified Wiener-Hammerstein System and Its Application in Electrically Stimulated Paralyzed Skeletal Muscle Modeling.

Electrical muscle stimulation demonstrates potential for restoring functional movement and preventing muscle atrophy after spinal cord injury (SCI). Control systems used to optimize delivery of electrical stimulation protocols depend upon mathematical models of paralyzed muscle force outputs. While accurate, the Hill-Huxley-type model is very complex, making it difficult to implement for real-time control. As an alternative, we propose a modified Wiener-Hammerstein system to model the paralyzed skeletal muscle dynamics under electrical stimulus conditions. Experimental data from the soleus muscles of individuals with SCI was used to quantify the model performance. It is shown that the proposed Wiener-Hammerstein system is at least comparable to the Hill-Huxley-type model. On the other hand, the proposed system involves a much smaller number of unknown coefficients. This has substantial advantages in identification algorithm analysis and implementation including computational complexity, convergence and also in real time model implementation for control purposes.

Preliminary experimental results on controlled cardiac computed tomography: a phantom study.

In this paper, we present the preliminary experimental results on controlled cardiac computed tomography (CT), which aims to reduce the motion artifacts by means of controlling the x-ray source rotation speed. An innovative cardiac phantom enables us to perform this experiment without modifying the scanner. It is the first experiment on the cardiac CT with speed controlled x-ray source. Experimental results demonstrate that the proposed method successfully separates the phantom images at different phases (improve the temporal resolution) through controlling the x-ray speed.

CPEB1 Expression Correlates with Severity of Posttraumatic Ankle Osteoarthritis and Aggravates Catabolic Effect of IL-1ß on Chondrocytes.

Most cases of posttraumatic ankle osteoarthritis (PTAOA) represent a sequela of ankle fractures. The cytoplasmic polyadenylation element-binding protein 1 (CPEB1) is an RNA binding protein that controls protein expression. Here, we report the previously unappreciated association of CPEB1 with PTAOA. We found that CPEB1 was upregulated in articular cartilage from patients with PTAOA. Additionally, its expression level positively correlated with disease severity. In human primary chondrocytes cultured in vitro, CPEB1 was upregulated when treated with pro-inflammatory cytokines, i.e., IL-1ß and TNF-α, suggesting that the observed CPEB1 upregulation in articular cartilage of PTAOA patients may be attributed to local inflammatory milieu. Functionally, CPEB1 overexpression aggravated the catabolic effect of IL-1ß on chondrocytes in vitro, and vice versa, its knockdown reduced this effect, together implying a detrimental role of CPEB1 involved in OA progression. In sum, our study identifies CPEB1 as a potential regulator of disease progression of PTAOA.

Bolus characteristics based on Magnetic Resonance Angiography.

BACKGROUND: A detailed contrast bolus propagation model is essential for optimizing bolus-chasing Computed Tomography Angiography (CTA). Bolus characteristics were studied using bolus-timing datasets from Magnetic Resonance Angiography (MRA) for adaptive controller design and validation. METHODS: MRA bolus-timing datasets of the aorta in thirty patients were analyzed by a program developed with MATLAB. Bolus characteristics, such as peak position, dispersion and bolus velocity, were studied. The bolus profile was fit to a convolution function, which would serve as a mathematical model of bolus propagation in future controller design. RESULTS: The maximum speed of the bolus in the aorta ranged from 5-13 cm/s and the dwell time ranged from 7-13 seconds. Bolus characteristics were well described by the proposed propagation model, which included the exact functional relationships between the parameters and aortic location. CONCLUSION: The convolution function describes bolus dynamics reasonably well and could be used to implement the adaptive controller design.

[The transformation of betA gene into the pollen plantlets of Populus simonii x P. nigra].

In this study, betA gene was introduced into the pollen plantlets of Populus simonii x P. nigra using Agrobacterium-mediated transformation. The four kanamycine-resistant plants obtained were identified as transgenic plants by PCR detection and the results were all positive. The result of quantitative real-time PCR detection showed that the betA gene was transcribed and expressed in all the transformed plants, but the transcript levels are different. Test of salt-tolerance of the transgenic plants showed that 80%-00% of transgenic plants were rooted while 0 of non-transgenic plants were rooted at 0.55% NaCl stress, and 0 of transgenic plants were rooted at 0.70%-0.80% NaCl stress. The betaine content analysis showed the betaine content of the transgenic plants are obviously higher than that in non-transgenic plants, so transformation betA gene raised the salt tolerance to the transgenic plants.

[Study of hereditary mode on handedness, preferential foot and hand-clasping].

The data of 21 families were analyzed by the method of Slater's calculating model to differentiate between single-gene and multi-gene heredity and by the method of non-deviation analysis. The results showed that the hereditary mode of handedness or preferential foot or hand-clasping is the dominant heredity of single gene of autosome, and the right type of all of them is the dominant character. In a way, although environmental factors affected the phenotypes of these characters,hereditary factors were also the decisive ones.