Microwave-assisted preparation of manganese dioxide modified activated carbon for adsorption of lead ions.

In this study, manganese dioxide was evenly distributed on the surface of activated carbon (AC), and the porous structure of AC and the surface functional groups of manganese dioxide were used to adsorb the heavy metal ion Pb(II). The advantages of microwave heating are fast heating and high selectivity. The mole ratio control of the AC and MnO2 in 1:0.1, microwave heating to 800 °C, heat preservation for 30 min. The maximum adsorption capacity of the MnO2-AC prepared by this method on Pb(II) can reach 664 mg/L at pH = 6. It can be observed by scanning electron microscope (SEM) that manganese dioxide particles are dispersed evenly on the surface and pore diameter of AC, and there is almost no agglomeration. The specific surface area was 752.8 m2/g, and the micropore area was 483.9 m2/g. The adsorption mechanism was explored through adsorption isotherm, adsorption kinetics, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). It is speculated that the adsorption mechanism includes electrostatic interaction and specific adsorption, indicating that lead ions enter into the void of manganese dioxide and form spherical complexes. The results showed that the adsorption behavior of Pb(II) by MnO2-AC was consistent with the Langmuir adsorption model, the quasi-second-order kinetic model, and the particle internal diffusion model.

Symptoms and signs associated with benign and malignant proximal fibular tumors: a clinicopathological analysis of 52 cases.

BACKGROUND: Malignant tumors in the proximal fibula are rare but life-threatening; however, biopsy is not routine due to the high risk of peroneal nerve injury. Our aim was to determine preoperative clinical indicators of malignancy. METHODS: Between 2004 and 2016, 52 consecutive patients with proximal fibular tumors were retrospectively reviewed. Details of the clinicopathological characteristics including age, gender, location of tumors, the presenting symptoms, the duration of symptoms, and pathological diagnosis were collected. Descriptive statistics were calculated, and univariate and multivariate regression were performed. RESULTS: Of these 52 patients, 84.6% had benign tumors and 15.4% malignant tumors. The most common benign tumors were osteochondromas (46.2%), followed by enchondromas (13.5%) and giant cell tumors (13.5%). The most common malignancy was osteosarcomas (11.5%). The most common presenting symptoms were a palpable mass (52.0%) and pain (46.2%). Pain was the most sensitive (100%) and fourth specific (64%); both high skin temperature and peroneal nerve compression had the highest specificity (98%) and third sensitivity (64%); change in symptoms had the second highest specificity (89%) while 50% sensitivity. Using multivariate regression, palpable pain, high skin temperature, and peroneal nerve compression symptoms were predictors of malignancy. CONCLUSIONS: Most tumors in the proximal fibula are benign, and the malignancy is rare. Palpable pain, peroneal nerve compression symptoms, and high skin temperature were specific in predicting malignancy.

Distribution patterns and coincidence of sesamoid bones at metatarsophalangeal joints.

PURPOSE: Our aim was to identify the incidence and distribution of sesamoid bones plantar to the metatarsophalangeal (MTP) joints in adults, and to evaluate patterns of coincidence among these sesamoid bones. METHODS: We conducted a retrospective review of 7949 plain radiographs obtained from patients evaluated for foot trauma or symptomology. Associations between the distributions of MTP sesamoid bones as well as the association of age, sex, and laterality with identified prevalence, distribution, and coincidence were evaluated using Spearman's correlation coefficient. RESULTS: Overall, 17,060 sesamoid bones were identified for 9005 MTP joints, with 16 distinctive distribution patterns. Among possible patterns, we identified a prevalence rate of complete absence of MTP sesamoid of 0.04 %, of a single sesamoid at the hallux of 89.08 % of radiographs; and of sesamoid at ≥2 MTP joints of 10.88 %. The presence of a sesamoid at the hallux was consistent, and was not correlated with the presence or absence of a sesamoid bone at one of the other MTP joints (P > 0.05). However, there was a positive correlation between the presence and absence of sesamoid bones at any two of the other four MTP joints (P < 0.001). Age was positively correlated with both the total number of sesamoids present (P < 0.001) and the number of MTP joints with sesamoids (P < 0.001). CONCLUSIONS: Information from this study would assist clinicians in the diagnosis of patients presenting with pain and discomfort of the foot after trauma and overuse, as well as contribute a robust data set for research in forensic science and anthropology.

[Analysis of risk factors for deep vein thrombosis of the lower extremity for patients with bone metastases].

OBJECTIVE: To analyze the risk factors for deep vein thrombosis (DVT) of the lower extremity in patients with bone metastases. METHODS: Ninety patients with bone metastases were admitted to our hospital From January 2010 to December 2011, and their clinical data were retrospectively analyzed. There were 57 males and 33 females with a mean age of 61 years (range, 27 to 78 years). On admission, all cases were detected by color Doppler ultrasonography for DVT of bilateral lower extremities. Univariate and multivariate analyses were performed to determine the probable risk factors including gender, age, body weight, tumor location, bed confinement and etc. RESULTS: Among the 90 patients, DVT was found in 24 patients on admission and the DVT incidence was 26.7% (24/90). The univariate analysis showed that bed confinement, multiple metastasis, pathological fracture, primary lesion detected, blood group, fibrinogen and hematocrit were significantly related to the incidence of DVT (P < 0.05). The logistic multivariate regression analysis showed that bed confinement, pathological fracture and fibrinogen were independent risk factors for the incidence of DVT. CONCLUSIONS: Bed confinement, pathological fracture and fibrinogen are independent risk factors for the incidence of DVT for patients with bone metastases. Patients with bed confinement >3 days, pathological fracture or fibrinogen >4 g/L should be routinely screened for lower extremity DVT on admission. Once identified, the DVT patients should be treated as early as possible.

Simulated warming enhances biological invasion of Solidago canadensis and Bidens frondosa by increasing reproductive investment and altering flowering phenology pattern.

Phenological and reproductive shifts of plants due to climate change may have important influences on population dynamics. Climate change may also affect invasive species by changing their phenology and reproduction, but few studies have explored this possibility. Here, we investigated the impact of climate change on the phenology, reproduction and invasion potential of two alien Solidago canadensis and Bidens frondosa and one native weed, Pterocypsela laciniata, all of which are in the Asteraceae family. The three species responded to simulated climate change by increasing reproductive investments and root/leaf ratio, prolonging flowering duration, and while the two alien species also displayed a mass-flowering pattern. Moreover, our experimental results indicated that the alien invasive species may have greater phenological plasticity in response to simulated warming than that of the native species (P. laciniata). As such, climate change may enhance the invasion and accelerate the invasive process of these alien plant species.

Simulated warming shifts the flowering phenology and sexual reproduction of Cardamine hirsuta under different Planting densities.

Climate warming can shift the reproductive phenology of plant, and hence dramatically reduced the reproductive capacity both of density-dependent and -independent plant species. But it is still unclear how climate warming affects flowering phenology and reproductive allocation of plant under different planting densities. Here, we assessed the impact of simulated warming on flowering phenology and sexual reproduction in the ephemeral herb Cardamine hirsuta under four densities. We found that simulated warming delayed the onset of flowering averagely for 3.6 days but preceded the end of flowering for about 1 day, which indicated climate warming shortened the duration of the flowering. And the flowering amplitude in the peak flowering day also dramatically increased in the simulated warming treatment, which caused a mass-flowering pattern. Climate warming significantly increased the weights of the fruits, seeds and seed, but reduced fruit length and sexual reproductive allocation under all the four densities. The duration of flowering was shortened and the weights of the fruits, seeds and seed, and sexual reproductive allocation were reduced under The highest density.

Prevalence, morphological variation and ossification of sesamoid bones of the forefoot: a retrospective radiographic study of 8,716 Chinese subjects.

Background and Aim: Previous studies provided evidence of a genetic basis for the occurrence of sesamoids bone in the foot among different ethnic populations. However, information for the Chinese population has not been previously reported. Therefore, the aim of our study was to determine the distribution, morphological variation and ossification timeline of sesamoid bones of the forefoot in a large sample of the Chinese population. Methods: Antero-posterior (AP) and oblique radiographs of 4,417 left and 4,299 right feet obtained from 8,716 patients in the Hebei province of Northern China, and retrospectively examined for the presence of sesamoid bones, identified as a small oval bone plantar to each metatarsophalangeal (MTP) joint and the first interphalangeal (IP) joint. Results and Conclusions: The prevalence rate of a sesamoid bone associated with the first to fifth MTP joints and the first IP joint was 99.96%, 3.08%, 0.39%, 0.69%, 8.94%, and 59.22%, respectively. Moreover, a morphological variation in hallucal sesamoids was identified in 12.09% of feet, with variations classified into three distinct types according to bone size and the number of ossification centers. Ossification begins in the hallucal MTP and IP joints at approximately 8 years of age, with the final ossification center being evidence for the sesamoid bone of the fourth MTP joint at 28 years of age. Relevance for patients: Our study provides important anatomical data regarding the prevalence of sesamoid bones in the forefoot of a large population of Chinese adult and pediatric patients for use in clinical practice and research in forensic science and anthropology.

[Temporal and spatial dynamics of reproductive modules of endangered plant Disanthus cercidifolius var. longipes natural populations].

Based on field observation data, this paper studied the flowering phenology and the temporal and spatial dynamics of the reproductive modules of endangered plant Disanthus cercidifolius var. longipes natural populations. The results showed that there were certain differences of the flowering phenology among the populations in different communities, e. g., in pure forest, the average flowering duration of individuals was the longest (75 d), while the flowering synchrony was the lowest (0.717 d), but in bamboo forest, the flowering duration of individuals was the shortest (47 d), while its flowering synchrony was the highest. The numbers of reproductive branches and inflorescences were increased with increasing individual age, and reached the highest at the age of 30 - 35 yr. At the elevation of 810 m, the numbers of individual reproductive branches and inflorescences reached the peak, and there were significant differences among the crown levels. The reproductive branch number of individuals and the inflorescences per reproductive branch were the highest in pure forest, being 411.39 and 7. 857, respectively, while the inflorescences per reproductive branch in bamboo forest were notably lower than those in other communities. The abortive ratio of reproductive modules of young individuals was higher than that of the older ones in the flower-bud, flowering, and fruit phases. The abortion of reproductive modules had no correlation with their distributed elevation, but some correlations existed with their development time, distributed crown levels and communities. The major factor affecting the abortive ratio of individual reproduction modules was probably the illumination condition in the distributed communities.