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The mandible is crucial for human physiological functions, as well as facial esthetics and expressions. The mandibular reconstruction surgery has dual challenges of restoration of both facial form and physiological function, which demands high precision in positioning and orientation of the bone graft. The traditional manual surgery heavily relies on surgeon’s experience. Although the computer image-guided surgery improves the positioning accuracy, the manual manipulation is still difficult to achieve precise spatial orientation of objects, resulting in unsatisfactory intraoperative execution of preoperative surgical design. This paper integrates computer image navigation and robotic technology to assist mandible reconstruction surgery, which empowers surgeons to achieve precise spatial localization and orientation adjustment of bone grafts. The kinematic analysis is conducted, and an improved Iterative Closest Point (ICP) algorithm is proposed for spatial registration. A novel hand-eye calibration method for multi-arm robot and spatial registration of free bone blocks are proposed. The precision experiment of the image-guided navigation and the animal experiments are carried out. The impact of registration point numbers on spatial registration accuracy is analyzed. The results show the feasibility of the robot-assisted navigation for mandibular reconstruction surgery. The robotic system can improve the orientation accuracy of bone blocks to enhance the effectiveness of surgery.
The pulse duration is a critical parameter of picosecond-petawatt laser systems because it directly affects the results of high-energy-density physics experiments. This study systematically investigated the effects of the spectral width, central wavelength and beam-pointing deviations on pulse duration stability at the SG-II facility. A theoretical analysis of the relationship between spectra and pulse duration is conducted to quantify the impact on pulse duration stability, and the results are further validated through experimental measurements. In addition, beam-pointing deviations at the stretcher significantly affect the pulse duration. For example, a 27 μrad deviation can induce a 30% pulse duration variation. In contrast, the compressor exhibits greater robustness. Based on simulation and experimental results, we identify operational tolerance ranges for spectral width and beam-pointing deviation to maintain pulse duration stability within 5% at the SG-II facility. These findings provide critical guidance for optimizing the performance and reliability of chirped-pulse amplification/optical parametric chirped-pulse amplification-based high-power laser systems.
Dietary n-3 PUFA may have potential benefits in preventing peptic ulcer disease (PUD). However, data from observational epidemiological studies are limited. Thus, we conducted a Mendelian randomisation analysis to reveal the causal impact of n-3 PUFA on PUD. Genetic variants strongly associated with plasma levels of total or individual n-3 PUFA including plant-derived α-linolenic acid and marine-derived EPA, DPA and DHA were enrolled as instrumental variables. Effect size estimates of the n-3 PUFA-associated genetic variants with PUD were evaluated using data from the UK biobank. Per one sd increase in the level of total n-3 PUFA in plasma was significantly associated with a lower risk of PUD (OR = 0·91; 95 % CI 0·85, 0·99; P = 0·020). The OR were 0·81 (95 % CI 0·67, 0·97) for EPA, 0·72 (95 % CI 0·58, 0·91) for DPA and 0·87 (95 % CI 0·80, 0·94) for DHA. Genetically predicted α-linolenic acid levels in plasma had no significant association with the risk of PUD (OR = 5·41; 95 % CI 0·70, 41·7). Genetically predicted plasma levels of n-3 PUFA were inversely associated with the risk of PUD, especially marine-based n-3 PUFA. Such findings may have offered an effective and feasible strategy for the primary prevention of PUD.
Intracytoplasmic sperm injection (ICSI) is a technique that directly injects a single sperm into the cytoplasm of mature oocytes. Here, we explored the safety of single-sperm cryopreservation applied in ICSI. This retrospective study enrolled 186 couples undergoing ICSI-assisted pregnancy. Subjects were allocated to the fresh sperm (group A)/single-sperm cryopreservation (group B) groups based on sperm type, with their clinical baseline/pathological data documented. We used ICSI-compliant sperm for subsequent in vitro fertilization and followed up on all subjects. The recovery rate/cryosurvival rate/sperm motility of both groups, the pregnancy/outcome of women receiving embryo transfer, and the delivery mode/neonatal-related information of women with successful deliveries were recorded. The clinical pregnancy rate, cumulative clinical pregnancy rate, abortion rate, ectopic pregnancy rate, premature delivery rate, live birth delivery rate, neonatal birth defect rate, and average birth weight were analyzed. The two groups showed no significant differences in age, body mass index, ovulation induction regimen, sex hormone [anti-Müllerian hormone (AMH)/follicle-stimulating hormone (FSH)/luteinizing hormone (LH)] levels, or oocyte retrieval cycles. The sperm recovery rate (51.72%-100.00%) and resuscitation rate (62.09% ± 16.67%) in group B were higher; the sperm motility in the two groups demonstrated no significant difference and met the ICSI requirements. Group B exhibited an increased fertilization rate, decreased abortion rate, and increased safety versus group A. Compared with fresh sperm, the application of single-sperm cryopreservation in ICSI sensibly improved the fertilization rate and reduced the abortion rate, showing higher safety.
The collector for separating diasporic bauxite serves as a type of flotation reagent by adsorbing selectively on diaspore to make it hydrophobic enough to separate it from the aluminosilicates. Although the flotation process is considered economical in the desilication of Chinese diasporic bauxite, the existing collectors fail to separate these ores because of their poor adsorption selectivity over other minerals. The present study was an attempt to seek a collector for selective flotation of diaspore over aluminosilicates. A novel carboxyl hydroxamic acid compound, 2,2-bis(hydroxycarbamoyl) decanoic acid (BHDA), was designed and synthesized, and the flotation behavior of diaspore, kaolinite, and illite was investigated by flotation tests with BHDA. The interactions between the BHDA and the minerals were also explored by Fourier-transform infrared spectroscopy (FTIR), zeta-potential measurement, and density functional theory (DFT) calculation. Using BHDA as the collector, the pulp pH value affected the floatability of diaspore significantly while the floatability of kaolinite or illite was unaffected or only slightly affected. The dosage of BHDA had little effect on the floatability of the three minerals. The greatest difference in floatability between diaspore and aluminosilicates occurred at mid-range pulp pH (7). Large shifts in characteristic absorption peaks and new absorption peaks were observed for BHDA-treated diaspore but were absent from BHDA-treated aluminosilicates. The change in the negative zeta potential of diaspore was also greater than those of aluminosilicates in the presence of BHDA. The O atoms in the carboxyl and hydroxycarbamoyl of BHDA have highly negative charges, and favorable stereo conditions existed to form five- or six-membered rings, resulting in their coordination with the Al atoms of diaspore, leading to chemisorption in chelate rings; the adsorption of BHDA on kaolinite or illite, on the other hand, was mainly physical in nature. The BHDA was, therefore, highly selective in the flotation between diaspore and aluminosilicates and possibly suitable for the separation of diasporic bauxite.
Retropharyngeal lymphadenectomy is challenging. This study investigated a minimally invasive approach to salvage retropharyngeal lymphadenectomy in patients with nasopharyngeal carcinoma.
Methods
An anatomical study of four fresh cadaveric heads was conducted to demonstrate the relevant details of retropharyngeal lymphadenectomy using the endoscopic transoral medial pterygomandibular fold approach. Six patients with nasopharyngeal cancer with retropharyngeal lymph node recurrence, who underwent retropharyngeal lymphadenectomy with the endoscopic transoral medial pterygomandibular fold technique at the Eye and ENT Hospital of Fudan University from July to December 2021, were included in this study.
Results
The anatomical study demonstrated that the endoscopic transoral medial pterygomandibular fold approach offers a short path and minimally invasive approach to the retropharyngeal space. The surgical procedure was well tolerated by all patients, with no significant post-operative complications.
Conclusion
The endoscopic transoral medial pterygomandibular fold approach is safe and efficient for retropharyngeal lymphadenectomy.
Everyone faces uncertainty on a daily basis. Two kinds of probability expressions, verbal and numerical, have been used to characterize the uncertainty that we face. Because our cognitive concept of living things differs from that of non-living things, and distinguishing cognitive concepts might have linguistic markers, we designed four studies to test whether people use different probability expressions when faced with animate or inanimate uncertainty. We found that verbal probability is the preferred way to express animate uncertainty, whereas numerical probability is the preferred way to express inanimate uncertainty. The “verbal-animate” and “numerical-inanimate” associations were robust enough to persist when tested with forced-choice response patterns regardless of the information (e.g., equally likely outcomes, frequencies, or personal beliefs) used to construct probabilities of events. When the response pattern was changed to free-responses, the associations were evident unless the subjects were asked to write their own probability predictions for vague uncertainty. Given that the world around us consists of both animate (i.e., living) and inanimate (i.e., non-living) things, “verbal-animate” and “numerical-inanimate” associations may play a major role in risk communication and may otherwise be useful for practitioners and consultants.
This study aimed to investigate the nurse-patient trust among in-patients in the context of the coronavirus disease (COVID-19) epidemic; it further analyzed the related influencing factors, which will provide a theoretical basis for developing corresponding measures.
Methods:
This study employed a mixed-method design and analyzed 149 patients at the Hongqi Hospital, affiliated with Mudanjiang Medical University, from December 2020 to February 2021. Quantitative analysis was carried out using the “Nurse Patient Trust Scale,” and qualitative analysis was performed using a semi-structured interview with in-patients.
Results:
The average score on the scale was 46.65 ± 2.83, and the scores of the 2 dimensions were: 23.24 ± 1.51 for ability and peace of mind, and 23.32 ± 1.53 for attitude and care. According to the interview data, the factors included 3 aspects: a comfortable hospital environment and humane management measures; the nurse’s own competence; and effective communication with patients.
Conclusion:
During the COVID-19 epidemic, there are still many factors affecting patients’ trust in nurses that can be addressed by taking different measures. All these factors must be considered by the relevant managers and clinical nursing staff to maintain a better nurse-patient trust relationship.
The study investigated novel wear and corrosion resistance of stainless steel and 316 stainless steel samples which were successfully prepared by laser melting deposition. Phase composition, microstructure, microhardness, wear resistance, and electrochemical corrosion resistance were studied. The experimental results showed that novel stainless steel was mainly composed of α-Fe and a few carbide phase (Cr, Fe)7C3. The microhardness of novel stainless steel was about 2.7 times greater than 316 stainless steel. Meanwhile, the specific wear rate of novel stainless steel and 316 stainless steel was 2.63 × 10−5 mm3/N m and 1.63 × 10−4 mm3/N m, respectively. The wear volume of 316 stainless steel was 6.19 times greater than novel stainless steel. The corrosion current and the corrosion potential of novel stainless steel and 316 stainless steel were 1.02 × 10−7 A/cm2 and 1.5 × 10−7 A/cm2, and −138.8 mV, −135.9 mV, respectively, in 3.5 wt% NaCl solution. Therefore, both microhardness and wear resistance of novel stainless steel were greatly improved, with high corrosion resistance.
Depression often coexists with other chronic conditions in older people. The COACH study is an ongoing random controlled trial (RCT) to test the effectiveness of a primary-care-based collaborative care approach to treat co-morbid hypertension and depression in Chinese rural elders. In the COACH model, a team—village doctor (VD), aging worker (AW), and psychiatrist consultant—provides collaborative care to enrolled subjects in each intervention village for 12 months. This study examines how COACH was implemented and identifies facilitators and barriers for its more widespread implementation.
Methods:
Five focus groups were conducted, two with VDs, two with AWs, and one with psychiatrists, for a total of 38 participants. Transcripts were analyzed using qualitative content analysis.
Results:
COACH care-team members showed shared understanding and appreciation of the team approach and integrated management of hypertension and depression. Team collaboration was smooth. All members regarded COACH to be effective in reducing depressive symptoms and improving patient health. Facilitators to implementation include training, leaders’ support, geographic proximity between VD and AW pairs, preexisting relationships among care-team members, comparability of COACH activities and existing practices of VDs and AWs, and care team members’ caring about older members of their villages. Barriers to sustainability include frustration of some VDs related to their low wages and feelings of overload of some AWs.
Conclusions:
COACH was positively perceived and successfully implemented. The findings offer guidance for planning primary-care-based collaborative depression care in low- and middle-income countries.
To explore whether and how group cognitive-behavioural therapy (GCBT) plus medication differs from medication alone for the treatment of generalised anxiety disorder (GAD).
Methods:
Hundred and seventy patients were randomly assigned to the GCBT plus duloxetine (n=89) or duloxetine group (n=81). The primary outcomes were Hamilton Anxiety Scale (HAMA) response and remission rates. The explorative secondary measures included score reductions from baseline in the HAMA total, psychic, and somatic anxiety subscales (HAMA-PA, HAMA-SA), the Hamilton Depression Scale, the Severity Subscale of Clinical Global Impression Scale, Global Assessment of Functioning, and the 12-item Short-Form Health Survey. Assessments were conducted at baseline, 4-week, 8-week, and 3-month follow-up.
Results:
At 4 weeks, HAMA response (GCBT group 57.0% vs. control group 24.4%, p=0.000, Cohen’s d=0.90) and remission rates (GCBT group 21.5% vs. control group 6.2%, p=0.004; d=0.51), and most secondary outcomes (all p<0.05, d=0.36−0.77) showed that the combined therapy was superior. At 8 weeks, all the primary and secondary significant differences found at 4 weeks were maintained with smaller effect sizes (p<0.05, d=0.32−0.48). At 3-month follow-up, the combined therapy was only significantly superior in the HAMA total (p<0.045, d=0.43) and HAMA-PA score reductions (p<0.001, d=0.77). Logistic regression showed superiority of the combined therapy for HAMA response rates [odds ratio (OR)=2.12, 95% confidence interval (CI) 1.02−4.42, p=0.04] and remission rates (OR=2.80, 95% CI 1.27−6.16, p=0.01).
Conclusions:
Compared with duloxetine alone, GCBT plus duloxetine showed significant treatment response for GAD over a shorter period of time, particularly for psychic anxiety symptoms, which may suggest that GCBT was effective in changing cognitive style.
l-Carnitine is essential for mitochondrial β-oxidation and has been used as a lipid-lowering feed additive in humans and farmed animals. d-Carnitine is an optical isomer of l-carnitine and dl-carnitine has been widely used in animal feeds. However, the functional differences between l- and d-carnitine are difficult to study because of the endogenous l-carnitine background. In the present study, we developed a low-carnitine Nile tilapia model by treating fish with a carnitine synthesis inhibitor, and used this model to investigate the functional differences between l- and d-carnitine in nutrient metabolism in fish. l- or d-carnitine (0·4 g/kg diet) was fed to the low-carnitine tilapia for 6 weeks. l-Carnitine feeding increased the acyl-carnitine concentration from 3522 to 10 822 ng/g and alleviated the lipid deposition from 15·89 to 11·97 % in the liver of low-carnitine tilapia. However, as compared with l-carnitine group, d-carnitine feeding reduced the acyl-carnitine concentration from 10 822 to 5482 ng/g, and increased lipid deposition from 11·97 to 20·21 % and the mRNA expression of the genes involved in β-oxidation and detoxification in the liver. d-Carnitine feeding also induced hepatic inflammation, oxidative stress and apoptosis. A metabolomic investigation further showed that d-carnitine feeding increased glycolysis, protein metabolism and activity of the tricarboxylic acid cycle and oxidative phosphorylation. Thus, l-carnitine can be physiologically utilised in fish, whereas d-carnitine is metabolised as a xenobiotic and induces lipotoxicity. d-Carnitine-fed fish demonstrates increases in peroxisomal β-oxidation, glycolysis and amino acid degradation to maintain energy homeostasis. Therefore, d-carnitine is not recommended for use in farmed animals.
Dalian, China, is a city free of rabies in recent 20 years, but the annual cost for rabies vaccination still brings an economic burden on society and individuals. We did a retrospective descriptive analysis to analyse the reason for this and try to find some ways to resolve it. A total of 10 028 post-exposure prophylaxis (PEP) cases were recorded from January 2016 to December 2017. According to the exposure grades, 32 cases were grade I; 7712 cases were grade II; 2284 cases were grade III. All the patients in the cases were injured by pet dogs without abnormal clinical signs, and 80% of them were home pet dogs. Fifty-two per cent of the pet dogs were vaccinated. All the dogs survived during the PEP vaccination period. The data showed that a considerable proportion of people who did not have exposure risk for rabies had received vaccination. The underlying reasons included social, medical and personal factors. So here we proposed to replace the current ‘five-course’ intramuscular injection with intradermal injection method in the cities free of rabies in China, this can not only achieve effective vaccination but also save resources and eliminate the fear of rabies from victims. Meanwhile we should strengthen communication on rabies knowledge and make a routine evaluation of rabies surveillance system to improve understanding of the risk for rabies from biting animals.
Hepatitis B constitutes a severe public health challenge in China. The Community-based Collaborative Innovation hepatitis B (CCI-HBV) project is a national epidemiological study of hepatitis B and has been conducting a comprehensive intervention in southern Zhejiang since 2009.
The comprehensive intervention in CCI-HBV areas includes the dynamic hepatitis B screening in local residents, the normalised treatment for hepatitis B infections and the upcoming full-aged hepatitis B vaccination. After two rounds of screening (each round taking for 4 years), the initial epidemiological baseline of hepatitis B in Qinggang was obtained, a coastal community in east China. By combining key data and system dynamics modelling, the regional hepatitis B epidemic in 20 years was predicted.
There were 1041 HBsAg positive cases out of 12 228 people in Round 1 indicating HBV prevalence of 8.5%. Of the 13 146 people tested in Round 2, 1171 people were HBsAg positive, with a prevalence of 8.9%. By comparing the two rounds of screening, the HBV incidence rate of 0.192 per 100 person-years was observed. By consulting electronic medical records, the HBV onset rate of 0.533 per 100 person-years was obtained. We generated a simulated model to replicate the real-world situation for the next two decades. To evaluate the effect of interventions on regional HBV prevalence, three comparative experiments were conducted.
In this study, the regional hepatitis B epidemic in 20 years was predicted and compared with HBV prevalence under different interventions. Owing to the existing challenges in research methodology, this study combined HBV field research and simulation to provide a system dynamics model with close-to-real key data to improve prediction accuracy. The simulation also provided a prompt guidance for the field implementation.
The effect of zirconium alloying on the crystal structures and mechanical properties of binary tungsten–zirconium alloys is investigated in this study using the first-principles method. Firstly, we investigate the cell volumes, lattice constants, and formation energies of binary W1−xZrx (x = 0, 0.0625, 0.125, 0.1875, 0.25, and 0.5) alloys. It is shown that binary tungsten–zirconium alloys maintain BCC structures. When the concentration of zirconium atoms is lower than 12.5%, the structures of binary tungsten–zirconium alloys can be thermodynamically stable. The elastic constants of binary tungsten–zirconium alloys are calculated based on the optimized atomic lattice. Then, the elastic modulus and other mechanical parameters are deduced according to the relevant formulas. It is shown that the mechanical strength of binary tungsten–zirconium alloy decreases with an increasing concentration of zirconium atoms, which is lower than the mechanical strength of pure tungsten metal. However, the mechanical strength of binary tungsten–zirconium alloys is higher than that of pure zirconium metal. In addition, zirconium alloying can be effective in improving the ductility of pure tungsten metal.
Northeastern China is a region of high tick abundance, multiple tick-borne pathogens and likely human infections. The spectrum of diseases caused by tick-borne pathogens has not been objectively evaluated in this region for clinical management and for comparison with other regions globally where tick-transmitted diseases are common. Based on clinical symptoms, PCR, indirect immunofluorescent assay and (or) blood smear, we identified and described tick-borne diseases from patients with recent tick bite seen at Mudanjiang Forestry Central Hospital. From May 2010 to September 2011, 42% (75/180) of patients were diagnosed with a specific tick-borne disease, including Lyme borreliosis, tick-borne encephalitis, human granulocytic anaplasmosis, human babesiosis and spotted fever group rickettsiosis. When we compared clinical and laboratory features to identify factors that might discriminate tick-transmitted infections from those lacking that evidence, we revealed that erythema migrans and neurological manifestations were statistically significantly differently presented between those with and without documented aetiologies (P < 0.001, P = 0.003). Twelve patients (6.7%, 12/180) were co-infected with two tick-borne pathogens. We demonstrated the poor ability of clinicians to identify the specific tick-borne disease. In addition, it is necessary to develop specific laboratory assays for optimal diagnosis of tick-borne diseases.
Coexisting scapolite, biotite and hornblende in scapolite-biotite rocks from the Tongmugou Pb-Zn deposit, Qinling, northwestern China are characterized by high levels of chlorine. Scapolite composition varies from EqAn27 to EqAn47 with 47–80 wt.% Cl. The scapolite composition is a sensitive indicator of the NaCl activity in coexisting hydrothermal fluid. Biotite contains 0.3–1.2 wt. % Cl and also has high F contents (0.2–0.7 wt.%). The hornblende is a Cl-rich hastingsite with Cl>3.5 wt.% and high (Na2O + K2O) contents (3.2–3.9 wt. %), high Xk [= K/(K + Na)] values (0.45–0.55) and high XFc [= Fe/(Fe + Mg)] values (0.76–0.79). The chlorine within these minerals is thought to be derived from evolved seawater. The scapolite-biotite rocks are products of Cl-rich alteration of volcanoclastic sedimentary rocks during submarine hydrothermal processes. Multiple-stage hydrothermal activity culminated with the circulation of a high-NaCl fluid that was also responsible for the formation of the massive sulphide deposits.
Electron-microprobe analyses of muscovite, biotite, and feldspar are reported for the stratiform Yindongzi—Daxigou Pb—Zn—Ag and Fe deposits of Qinling, northwestern China. The micas are characterized by high Ba levels in banded albite-carbonate rocks that host the deposits. The biotite is also rich in Cl, as is biotite in the nearby Tongmugou Pb-Zn deposit, although biotite and muscovite from this deposit lack Ba enrichment. It is likely that the Ba-rich micas in the Yindongzi-Daxigou deposits formed contemporaneously from the diagenesis and/or regional metamorphism of hydrothermally altered clay minerals, with the barium being derived from entrained pore fluids that may represent relict hydrothermal fluids associated with ore deposition. During the formation of coexisting muscovite and biotite, barium is preferentially partitioned into muscovite and chloride into biotite. Together with the presence of baryte rocks in the bedded ores, these data suggest that ore deposition in the Yindongzi—Daxigou deposits took place in a more oxidising environment than in the nearby Tongmugou deposit. This difference is attributed to the contrasting sedimentary environments of the two deposits, with the Yindongzi—Daxigou deposits having formed under shallow, oxic conditions and the Tongmugou deposit under deeper, anoxic conditions.
A high power laser system was used to drive the ignition of inertial confinement fusion (ICF), of which the high energy, the uniform focal spot, the accurate laser waveform, and the synchronization between the laser beams are key parameters. To accomplish this, global laser characteristics control should be assured, which was the main purpose of the injection laser system. In this paper, the key technological progress involved in the improvement of the performance of the injection laser of SG-II is reported, including frequency domain control, time domain control, near-field spatial shaping, pre-amplifier technology, and the optical parametric chirped pulse amplification pump source.
Consider the scattering of a time-harmonic acoustic incident wave by a bounded, penetrable, and isotropic elastic solid, which is immersed in a homogeneous compressible air or fluid. The paper concerns the numerical solution for such an acoustic-elastic interaction problem in three dimensions. An exact transparent boundary condition (TBC) is developed to reduce the problem equivalently into a boundary value problem in a bounded domain. The perfectly matched layer (PML) technique is adopted to truncate the unbounded physical domain into a bounded computational domain. The well-posedness and exponential convergence of the solution are established for the truncated PML problem by using a PML equivalent TBC. An a posteriori error estimate based adaptive finite element method is developed to solve the scattering problem. Numerical experiments are included to demonstrate the competitive behavior of the proposed method.