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The aim of this study was to analyze the profile of chest injuries, oxygen therapy for respiratory failure, and the outcomes of victims after the Jiangsu tornado, which occurred on June 23, 2016 in Yancheng City, Jiangsu Province, China.
The clinical records of 144 patients referred to Yancheng City No.1 People’s Hospital from June 23 through June 25 were retrospectively investigated. Of those patients, 68 (47.2%) sustained major chest injuries. The demographic details, trauma history, details of injuries and Abbreviated Injury Scores (AIS), therapy for respiratory failure, surgical procedures, length of intensive care unit (ICU) and hospital stay, and mortality were analyzed.
Of the 68 patients, 41 (60.3%) were female and 27 (39.7%) were male. The average age of the injured patients was 57.1 years. Forty-six patients (67.6%) suffered from polytrauma. The mean thoracic AIS of the victims was calculated as 2.85 (SD = 0.76). Rib fracture was the most common chest injury, noted in 56 patients (82.4%). Pulmonary contusion was the next most frequent injury, occurring in 12 patients (17.7%). Ten patients with severe chest trauma were admitted to ICU. The median ICU stay was 11.7 (SD = 8.5) days. Five patients required intubation and ventilation, one patient was treated with noninvasive positive pressure ventilation (NPPV), and four patients were treated with high-flow nasal cannula (HFNC). Three patients died during hospitalization. The hospital mortality was 4.41%.
Chest trauma was a common type of injury after tornado. The most frequent thoracic injuries were rib fractures and pulmonary contusion. Severe chest trauma is usually associated with a high incidence of respiratory support requirements and a long length of stay in the ICU. Early initiation of appropriate oxygen therapy was vital to restoring normal respiratory function and saving lives. Going forward, HFNC might be an effective and well-tolerated therapeutic addition to the management of acute respiratory failure in chest trauma.
This study aimed to determine whether increased carotenoids intake was associated with reduced risk of gestational diabetes mellitus (GDM). We performed a cross-sectional analysis using data from Tongji Maternal and Child Health Cohort study. The dietary carotenoids intake of 1978 pregnant women was assessed using a researcher-administered FFQ before undertaking an oral glucose tolerance test at 24–28 weeks. Multivariate logistic and linear regression analyses were used to obtain the effect estimates. Participants in the highest quartile of lycopene intake showed a lower risk of GDM (OR 0·50; 95 % CI 0·29, 0·86; Pfor trend = 0·007) compared with those in the lowest quartile; each 1 mg increase in lycopene consumption was associated with a 5 % (95 % CI 0·91, 0·99; Pfor trend = 0·020) decrease in GDM risk. No significant association was found between α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin intake and GDM risk. Multiple linear regression analysis suggested an inverse association between lycopene intake and fasting blood glucose (FBG) (Pfor trend < 0·001); each 1 mg increase in lycopene intake was associated with 0·005 (95 % CI 0·002, 0·007; Pfor trend < 0·001) mmol/l decrease in FBG. Interaction analysis indicated consistent effect on each age or pre-BMI subgroup; however, a stronger protective effect of lycopene intake against GDM was observed among primigravid women (OR 0·20; 95 % CI 0·07, 0·55 in the highest v. the lowest quartile of intake; Pfor interaction = 0·036). In conclusion, dietary lycopene intake was mainly assumed via reducing FBG to decrease GDM risk, and the protection was relatively increased among primigravid women.
The piezophotonic effect is the coupling between piezoelectric properties and photoexcitation, where strain-induced piezopotential modulates and controls the relevant optical process. Specifically, metal ions as activators are capable of responding to photoexcitation and subsequent emission of light, also called mechanoluminescence, in general, and piezoluminescence specifically for piezoelectrics. These phenomena are helpful for understanding the materials fundamentals and conceiving widespread device applications. In this article, we briefly introduce the physical mechanisms of piezophotonics, including piezoluminescence. Selected host materials and metal-ion activators are described for demonstrating the piezophotonic effect. We provide a unified profile and recent prototypical demonstrations of light emission triggered by mechanical stimuli. The devices based on these materials offer the advantages of remote detection, nondestructive analysis, and repeatability, hence they are promising candidates for applications in stress sensing, structural health diagnosis, three-dimensional handwriting, magnetic-optical sensing, energy harvesting, biomedicine, novel light sources, and displays.
Harnessing the nonvolatility of magnetism and the power of electric control, magnetoelectric devices that control magnetism electrically promise to deliver next-generation electronics systems that can store and compute large amounts of information with minimal power consumption and ultrafast processing speed. We highlight progress in magnetoelectric memory and logic prototypes using the voltage-controlled magnetic anisotropy (VCMA) effect. First, important performance metrics of VCMA-based magnetoelectric random access memory (MeRAM) are benchmarked against embedded complementary metal oxide semiconductor and other emerging embedded nonvolatile memories. We then discuss scaling of MeRAM from the physics and materials perspectives of the VCMA effect, as well as the use of magnetoelectric logic devices and circuits to realize new computing paradigms with VCMA. Finally, challenges to realize the full potential of VCMA-based memory and logic are presented: VCMA coefficient of 1000 fJ/V-m for energy-efficient write with low errors and tunneling magnetoresistance of 1000% for high density and low noise margin readout. New approaches for deterministic switching based on VCMA are needed. We share perspectives to address these challenges using new materials and device operation schemes.
Maternal dietary patterns and macronutrients intake have been shown to affect the development of gestational diabetes mellitus (GDM), but the findings are inconsistent. We aimed to identify maternal dietary patterns and examine their associations with GDM risk, and to evaluate the contributions of macronutrients intake to these associations. We included 2755 Chinese pregnant women from the Tongji Maternal and Child Health Cohort. Dietary intakes were assessed using a validated semi-quantitative FFQ 2 weeks before the diagnosis of GDM. GDM (n 248) was diagnosed based on the results of a 75-g, 2-h oral glucose tolerance test at 24–28 weeks gestation. We derived five different dietary patterns from a principal component analysis. The results showed that high fish–meat–eggs scores, which were positively related to protein intake and inversely related to carbohydrate intake, were associated with a higher risk of GDM (adjusted OR for quartile 4 v. quartile 1: 1·83; 95 % CI 1·21, 2·79; Ptrend=0·007) and higher plasma glucose levels. In contrast, high rice–wheat–fruits scores, which were positively related to carbohydrate intake and inversely related to protein intake, were associated with lower risk of GDM (adjusted OR for quartile 3 v. quartile 1: 0·54; 95 % CI 0·36, 0·83; Ptrend=0·010) and lower plasma glucose levels. In addition, dietary protein and carbohydrate intake significantly contributed to the associations between dietary patterns and GDM risk or glucose levels. These findings suggest that a dietary pattern characterised by high protein and low carbohydrate intake in pregnancy was associated with a higher risk of GDM, which may provide important clues for dietary guidance during pregnancy to prevent GDM.
For the first time, an experiment has been conducted to investigate synthetic jet laminar vortex rings impinging onto porous walls with different geometries by time-resolved particle image velocimetry. The geometry of the porous wall is changed by varying the hole diameter on the wall (from 1.0 mm to 3.0 mm) when surface porosity is kept constant (
). The finite-time Lyapunov exponent and phase-averaged vorticity field derived from particle image velocimetry data are presented to reveal the evolution of the vortical structures. A mechanism associated with vorticity cancellation is proposed to explain the formation of downstream transmitted vortex rings; and both the vortex ring trajectory and the time-mean flow feature are compared between different cases. It is found that the hole diameter significantly influences the evolution of the flow structures on both the upstream and downstream sides of the porous wall. In particular, for a porous wall with a small hole diameter (
, 0.10 and 0.133), the transmitted finger-type jets will reorganize into a well-formed transmitted vortex ring in the downstream flow. However, for the case of a large hole diameter of
, the transmitted vortex ring is not well formed because of insufficient vorticity cancellation. Additionally, the residual vorticity gradually evolves into discrete jet-like structures downstream, which further weaken the intensity of the transmitted vortex ring. Consequently, the transmitted flow structures for the
case would lose coherence more easily (or probably even transition to turbulence), resulting in a faster decay of the axial velocity and stronger entrainment of the transmitted jet. For all porous wall cases, the velocity profile of the transmitted jet exhibits self-similar behaviour in the far field (
), which agrees well with the velocity distribution of free synthetic jets. With the help of the control-volume approach, the time-mean drag of the porous wall is evaluated experimentally for the first time. It is shown that the porous wall drag increases with the decrease in the hole diameter. Moreover, for a porous wall with a small hole diameter (
, 0.10 and 0.133), it appears that the porous wall drag mainly derives from the viscous effect. However, as
increases to 0.20, the form drag associated with the porous wall geometry becomes significant.
In this paper, we introduce a lower extremity exoskeleton CUHK-EXO that is developed to help paraplegic patients, who have lost the motor and sensory functions of their lower limbs to perform basic daily life motions. Since the sit-to-stand and stand-to-sit (STS) motion is the first step for paraplegic patients toward walking, analysis of the exoskeleton's applicability to the STS motion assistance is performed. First, the human-exoskeleton system (HES) is modeled as a five-link model during the STS motion, and the center of pressure (COP) on the ground and center of gravity of the whole system are calculated. Then, a description of the CUHK-EXO hardware design is presented, including the mechatronics design and actuator selection. The COP position is an important factor indicating system balance and wearer's comfort. Based on the COP position, a trajectory online modification algorithm (TOMA) is proposed for CUHK-EXO to counteract disturbances, stabilize system balance, and improve the wearer's comfort in the STS motion. The results of STS motion tests conducted with a paraplegic patient demonstrate that CUHK-EXO can provide a normal reference pattern and proper assistive torque to support the patient's STS motion. In addition, a pilot study is conducted with a healthy subject to verify the effectiveness of the proposed TOMA under external disturbances before future clinical trials. The testing results verify that CUHK-EXO can counteract disturbances, and help the wearer perform the STS motion safely and comfortably.
The effects of different Fe contents (0.168, 0.356 and 0.601 wt%) on microstructures and mechanical properties of the Al–1.6Mg–1.2Si–1.1Cu–0.15Cr–0.15Zr (all in wt%) alloys prepared by low frequency electromagnetic casting process were investigated in the process of solidification, hot extrusion, solid solution and aging treatments. The results show that the increase of Fe content promotes the formation of feathery grains in the process of solidification and the precipitation of another important strengthening phase Q′ with small size. Additionally, it also results in no recrystallization even after solid solution at a high temperature of 550 °C, which is because of the increase number of elliptical shaped and fine DO22-Al3Zr dispersoids (∼70 nm long and ∼35 nm wide) and the spherical or elliptical shaped Fe-containing phases. When Fe content of the alloy increases to 0.356 wt%, both the ultimate tensile strength and yield strength of the alloy-T6 increase by more than 60 MPa and with little cost of ductility.
This article outlines the evolution of a rescue team in responding to adenovirus prevention with a deployable field hospital. The local governments mobilized a shelter hospital and a rescue team consisting of 59 members to assist with rescue and response efforts after an epidemic outbreak of adenovirus. We describe and evaluate the challenges of preparing for deployment, field hospital maintenance, treatment mode, and primary treatment methods. The field hospital established at the rescue scene consisted of a medical command vehicle, a computed tomography shelter, an X-ray shelter, a special laboratory shelter, an oxygen and electricity supply vehicle, and epidemic prevention and protection equipment. The rescue team comprised paramedics, physicians, X-ray technicians, respiratory therapists, and logistical personnel. In 22 days, more than 3000 patients with suspected adenovirus infection underwent initial examinations. All patients were properly treated, and no deaths occurred. After emergency measures were implemented, the spread of adenovirus was eventually controlled. An emergency involving infectious diseases in less-developed regions demands the rapid development of a field facility with specialized medical personnel when local hospital facilities are either unavailable or unusable. An appropriate and detailed prearranged action plan is important for infectious diseases prevention. (Disaster Med Public Health Preparedness. 2018;12:109–114)
Disaster can strike people in any community at any time anywhere in the world. Disasters occur with high frequency, take on multiple forms, and exert wide influence, typically causing property damage, injuries, and death. As the world’s largest developing country, China incurs great costs when a disaster hits. After the Wenchuan earthquake in 2008, the Chinese government focused its attention on the construction of an emergency response system, the creation of disaster prevention and mitigation systems, and the development of a disaster medicine program. Here, we describe the current status of disaster medicine in China, focusing on the following four aspects: the Emergency Management System, Education & Training, Rescue Practices, and Research. We also discuss the future of disaster medicine in China. (Disaster Med Public Health Preparedness. 2018;12:157–165)
This article is devoted to the study of some high-order difference schemes for the distributed-order time-fractional equations in both one and two space dimensions. Based on the composite Simpson formula and Lubich second-order operator, a difference scheme is constructed with convergence in the L1(L∞)-norm for the one-dimensional case, where τ,h and σ are the respective step sizes in time, space and distributed-order. Unconditional stability and convergence are proven. An ADI difference scheme is also derived for the two-dimensional case, and proven to be unconditionally stable and convergent in the L1(L∞)-norm, where h1 and h2 are the spatial step sizes. Some numerical examples are also given to demonstrate our theoretical results.
To determine dynamic changes in clinical characteristics by examining an outbreak of adenovirus infection that occurred from December 20, 2012, to February 25, 2013, in Tianjin, China.
Active surveillance for febrile respiratory illnesses was conducted, and medical records of patients were collected. Real-time quantitative polymerase chain reaction and sequencing were used for pathogen identification and viral genome study, respectively. Student’s t-test was used to compare the mean values of normally distributed continuous variables. Mann-Whitney U or Kruskal-Wallis tests were used if continuous variables were not normally distributed. Pearson’s chi-square test or Fisher’s exact test was used to compare categorical variables.
The outbreak was sourced from the index case diagnosed as the common cold on December 20, 2012; a total of 856 cases were reported in the following 66 days. The pathogen was identified as human adenovirus (HAdV) 55. The symptoms manifested differently in severe and mild cases. Routine blood examinations, liver function indexes, and heart function indexes showed different dynamic patterns over time in hospitalized patients.
Clinical characteristics and laboratory examinations may reveal unique patterns over the course of HAdV-55 infection. (Disaster Med Public Health Preparedness. 2018;12:464–469)
X-ray powder diffraction data, unit-cell parameters and space group for gemcitabine, C9H11F2N3O4, are reported [a = 17.641(8) Å, b = 6.985(1) Å, c = 18.653(2) Å, α = β = γ = 90°, unit-cell volume V = 2298.61 Å3, Z = 8 and space group Pmna]. All measured lines were indexed and are consistent with the Pmna space group. No detectable impurities were observed.
In this paper, the robust, optimal, output control problem is dealt with for a 3-degree-of-freedom laboratory helicopter. The control goal is to achieve the practical tracking of the desired elevation and pitch angles without the angular velocity feedback. A nominal linear time-invariant system is introduced and the real system is considered as the nominal one with uncertainties, including parameter perturbations, nonlinear time-varying uncertainties, and external disturbances. An observer is first used to estimate angular velocity. Then a nominal controller based on the optimal control method is designed for the nominal system to achieve the desired tracking properties. Lastly, a robust output compensator is added to restrain the effects of uncertainties in the real system. It is shown that asymptotic tracking properties and robust stability can be achieved. Experimental results on the laboratory helicopter are shown to verify the effectiveness of the proposed control method.
Photoperiods influence diapause beyond the maternal generation in Cotesia vestalis (Haliday) (Hymenoptera: Braconidae). The sizes, 20-hydroxyecdysone (20E), and juvenile hormone III (JH III) contents in the G1 diapausing prepupae, G0 nondiapausing prepupae, adults, and G1 eggs from C. vestalis cultures reared under three photoperiods (8:16 hours light:dark, 12:12 hours light:dark, and 16:8 hours light:dark) were measured to investigate the hormones’ roles on maternal information transmission and diapause regulation. Results showed that the body size of G1 diapausing prepupae was significantly larger than that of G0 nondiapausing prepupae. The sizes of G0 prepupae, female abdomens, and G1 eggs under eight-hour light were significantly larger than those under 16-hour light. The 20E content in diapausing prepupae was significantly lower than that in nondiapausing prepupae, whereas JH III content did not show significantly difference under the same photoperiod. The 20E content in maternal prepupae, mated females and G1 eggs decreased as the light period was reduced. Juvenile hormone III contents in G0-mated females and G1 eggs (after oviposition) under three photoperiods showed no significant differences. These findings suggest that 20E may play a critical role in diapause regulation of C. vestalis, and be used as a maternal environmental message to be transmitted to the next generation.
In this study, crystal orientation and polymorphism formation in electrospun poly(vinylidene fluoride) (PVDF)/polyacrylonitrile (PAN) blend fibers after melt-recrystallization were studied. To achieve uniform alignment of electrospun fibers, mechanical stretching was applied to the as-spun nonwoven fibers at 110 °C. Pure ferroelectric β-PVDF crystals in the PAN matrix were achieved, and both polar β-PVDF and polar PAN crystals oriented with their chain axes parallel to the fiber axes. After melt-recrystallization of PVDF, a significant amount of ferroelectric β crystals was retained in addition to the formation of nonpolar α crystals. A polarized Fourier transform infrared study showed that the degree of orientation of ferroelectric β-PVDF crystals was higher than that of nonpolar α crystals, suggesting that the β-PVDF crystals should form at the PVDF/PAN interfaces because of strong dipolar and hydrogen bonding interactions between vinylidene fluoride and acrylonitrile units. The nonpolar α-PVDF crystals should form in the center of PVDF domains.
Growing evidence shows that the deregulation of the circadian clock plays an important role in the development of malignant tumors, including gliomas. However, the molecular mechanisms of genes controlling circadian rhythm in glioma cells have not been explored.
Using reverse transcription polymerase chain reaction and immunohistochemistry techniques, we examined the expression of two important clock genes, Per1 and Per2, in 33 gliomas.
In this study, out of 33 gliomas, 28 were Per1-positive, and 23 were Per2-positive. The expression levels of Per1 and Per2 in glioma cells were significantly different from the surrounding non-glioma cells (P<0.01). The difference in the expression rate of Per1 and Per2 in high-grade (grade III and IV) and low-grade (grade 1 and II) gliomas was insignificant (P>0.05). While there was no difference in the intensity of immunoactivity for Per2 between high-grade gliomas and low-grade gliomas (r=-0.330, P=0.061), the expression level of Per1 in highgrade gliomas was significantly lower than that in low-grade gliomas(r=-0.433, P=0.012).
In this study, we found that the expression of Per1 and Per2 in glioma cells was much lower than in the surrounding non-glioma cells. Therefore, we suggest that disturbances in Per1 and Per2 expression may result in the disruption of the control of normal circadian rhythm, thus benefiting the survival of glioma cells. Differential expression of circadian clock genes in glioma and non-glioma cells may provide a molecular basis for the chemotherapy of gliomas.
We previously reported that translocation of mitochondria from the oocyte cortex to the perinuclear area indicates positive developmental potential that was reduced in porcine somatic cell nuclear transfer (SCNT) embryos compared to in vitro–fertilized (IVF) embryos (Katayama, M., Zhong, Z.-S., Lai, L., Sutovsky, P., Prather, R.S. & Schatten, H. (2006). Dev Biol299, 206–220.). The present study is focused on distribution of donor cell mitochondria in intraspecies (pig oocytes; pig fetal fibroblast cells) and interspecies (pig oocytes; mouse fibroblast cells) reconstructed embryos by using either pig fibroblasts with mitochondria-stained MitoTracker CMXRos or YFP-mitochondria 3T3 cells (pPhi-Yellow-mito) as donor cells. Transmission electron microscopy was employed for ultrastructural analysis of pig oocyte and donor cell mitochondria. Our results revealed donor cell mitochondrial clusters around the donor nucleus that gradually dispersed into the ooplasm at 3 h after SCNT. Donor-derived mitochondria distributed into daughter blastomeres equally (82.8%) or unequally (17.2%) at first cleavage. Mitochondrial morphology was clearly different between donor cells and oocytes in which various complex shapes and configurations were seen. These data indicate that (1) unequal donor cell mitochondria distribution is observed in 17.2% of embryos, which may negatively influence development; and (2) complex mitochondrial morphologies are observed in IVF and SCNT embryos, which may influence mitochondrial translocation and affect development.