Measurements and Modelling of Thermally Induced Warpages of DIMM Socket Server PCB Assembly after Solder Reflow Processes.

The thermal warpage of a server-computer-used DIMM socket-PCB assembly after the solder reflow process is studied experimentally, theoretically, and numerically, especially along the socket lines and over the entire assembly. Strain gauge and shadow moiré are used for determining the coefficients of thermal expansion of the PCB and DIMM sockets and for measuring the thermal warpages of the socket-PCB assembly, respectively, while a newly proposed theory and a finite element method (FEM) simulation are used to calculate the thermal warpage of the socket-PCB assembly in order to understand its thermo-mechanical behavior and then further identify some important parameters. The results show that the theoretical solution validated by the FEM simulation provides the mechanics with the critical parameters. In addition, the cylindrical-like thermal deformation and warpage, measured by the moiré experiment, are also consistent with the theory and FEM simulation. Moreover, the results of the thermal warpage of the socket-PCB assembly from the strain gauge suggest a warpage dependence on the cooling rate during the solder reflow process, due to the nature of the creep behavior in the solder material. Finally, the thermal warpages of the socket-PCB assemblies after the solder reflow processes are provided through a validated FEM simulation for future designs and verification.

[Effect of Shh and BM-MSC Synergism on the Proliferation of Hematopoietic Stem Cells].

OBJECTIVE: To study the effect and mechanism of shh and mesenchymal stem cell（MSC）synergism on the proliferation of hematopoietic stem cells in noninvasive co-culture system in vitro. METHODS: The mesenchymal stem cells were cultured in vitro，CD34+ cells were sorted by mini MACS magnetic bead separator，flow cytometry was used to identify the purity of 2 cells. CD34+ cells and MSCs were seeded to upper and low of transwell respecibely for non-contact coculture，and add exogenous shh protein for intervenece. The number of MSCs and HSCs，the total amount of RNA，the expression of ki67 and Tie-2 mRNA of HSC，the expression of VEGF and Ang-1 mRNA of MSC were detected for investigating the condition of cell proliferation and the expression of angiogenic factors. RESULTS: The total number of cells，the total amount of RNA and the relative expression of ki67, Tie-2, VEGF and Ang-1 in non-contact co-culture group increased and showed the following trends on the 7th day：the above-mentioned indexes in group MSC + HSC, group shh + HSC were higher than those in group HSC, while those in MSC + shh + HSC Group was higher than those in MSC + HSC and shh + HSC group. CONCLUSION: Angiogenic factors help MSC to proliferate HSC and amplify the CD34+ hematopoietic stem/progenitor cells by shh and MSC synergism in vitro coculture system which may be related with angiogenic factors.

[Influencing Factors of Nosocomial Infection after Chemotherapy in Adult Patients with Acute Myeloid Leukemia and Its Control Strategy].

OBJECTIVE: To investigate the influencing factors of nosocomial infection in adult patients with acute myeloid leukemia (AML) and its control strategies. METHODS: The clinical data of 109 patients with AML treated in our hospital from June 2014 to June 2017 were retrospectively analyzed. The clinical factors were analyzed retrospectively, and the influencing factors of infection after chemotherapy were explored. RESULTS: A total of 109 patients received chemotherapy for 267 case-times, the infection occurred in 168 case-times, the nosocomial infection rate was 62.92%, the main affected sites included upper respiratory tract and lung. 155 samples from 168 case-times infection patients were collected and cultured, 32 pathogens were obtained with a positive rate 20.6% (32/155), including 14 Gram-negative bacteria, 9 Gram-positive bacteria and 4 strains of fungi and 5 strains of other pathogens. Statistics showed that the patient's age over 40 years old, hospitalization in spring and summer, glucocorticoid therapy, high intensity chemotherapy, neutrophil count, white blood cell count and hemoglobin content were the independent risk factors for infection after chemotherapy in AML patients (P<0.05). CONCLUSION: The age of more than 40 years old, hospitalization in spring and summer, glucocorticoid therapy, high-intensity chemotherapy, white blood cell count, neutrophil count and hemoglobin content are the independent risk factors for infection after chemotherapy in the AML patients with the above-mentioned characteristics, they should be closely monitored, and chemotherapy intensity should be controled, so as to control the occurrence of infection; and in the event of infection, a timely powerful anti-infective treatment would be indispensable.

Effect of Shh and BM-MSC Synergism on the Proliferation of Hematopoietic Stem Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To study the effect and mechanism of shh and mesenchymal stem cell（MSC）synergism on the proliferation of hematopoietic stem cells in noninvasive co-culture system in vitro.</p><p><b>METHODS</b>The mesenchymal stem cells were cultured in vitro，CD34 cells were sorted by mini MACS magnetic bead separator，flow cytometry was used to identify the purity of 2 cells. CD34 cells and MSCs were seeded to upper and low of transwell respecibely for non-contact coculture，and add exogenous shh protein for intervenece. The number of MSCs and HSCs，the total amount of RNA，the expression of ki67 and Tie-2 mRNA of HSC，the expression of VEGF and Ang-1 mRNA of MSC were detected for investigating the condition of cell proliferation and the expression of angiogenic factors.</p><p><b>RESULTS</b>The total number of cells，the total amount of RNA and the relative expression of ki67, Tie-2, VEGF and Ang-1 in non-contact co-culture group increased and showed the following trends on the 7th day：the above-mentioned indexes in group MSC + HSC, group shh + HSC were higher than those in group HSC, while those in MSC + shh + HSC Group was higher than those in MSC + HSC and shh + HSC group.</p><p><b>CONCLUSION</b>Angiogenic factors help MSC to proliferate HSC and amplify the CD34 hematopoietic stem/progenitor cells by shh and MSC synergism in vitro coculture system which may be related with angiogenic factors.</p>

Coculture with mesenchymal stem cells facilitates the proliferation of hematopoietic stem cells under different coculture modes / 中国组织工程研究

BACKGROUND: Although a large number of related studies have been carried out, there is still a lack of practical methods to amplify hematopoietic stem cells(HSCs)in vitro.Mesenchymal stem cells(MSCs)secrete a variety of cytokines that promote the HSCs proliferation and inhibit their differentiation. These cytokines play an important role in maintaining the hematopoietic microenvironment and regulating HSCs function. OBJECTIVE:To investigate the effect of bone marrow MSCs on the proliferation of HSCs in vitro under different coculture modes. METHODS:Mesenchymal stem cells from the bone marrow of C57BL/6 mice were cultured in vitro using the whole bone marrow adherent culture. CD117+cells (HSCs) were sorted from passage 3 cells by using miniMACS magnetic beads sorting. Then, CD117+cells were co-cultured with MSCs under different coculture models, including single culture of HSCs (control group), Transwell coculture (upper chamber, HSCs; lower chamber, MSCs) and two-dimensional contact coculture (coculturing HSCs and MSCs in 24-well plates). The morphology of HSCs was observed under phase contrast microscope and fluorescence microscope, and the number of active cells of HSCs was counted at 1, 3, 5, and 7 days after coculture. RESULTS AND CONCLUSION: During the coculture of 1-7 days, the number of HSCs in the two groups was increased with culture time (P <0.05). After 3 days of coculture, HSCs in each group was grown into the logarithmic growth phase, and morphological changes in some HSCs were detected at 5 days of coculture. At 7 days of coculture, the viabilities of HSCs in different culture models were ranked as follows: single culture model < Transwell coculture model < two-dimensional contact coculture model (P < 0.05). These findings suggest that MSCs can effectively promote the proliferation of HSCs in vitro,and the promotion effect is increased under contact coculture conditions.

Influencing Factors of Nosocomial Infection after Chemotherapy in Adult Patients with Acute Myeloid Leukemia and Its Control Strategy / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the influencing factors of nosocomial infection in adult patients with acute myeloid leukemia (AML) and its control strategies.</p><p><b>METHODS</b>The clinical data of 109 patients with AML treated in our hospital from June 2014 to June 2017 were retrospectively analyzed. The clinical factors were analyzed retrospectively, and the influencing factors of infection after chemotherapy were explored.</p><p><b>RESULTS</b>A total of 109 patients received chemotherapy for 267 case-times, the infection occurred in 168 case-times, the nosocomial infection rate was 62.92%, the main affected sites included upper respiratory tract and lung. 155 samples from 168 case-times infection patients were collected and cultured, 32 pathogens were obtained with a positive rate 20.6% (32/155), including 14 Gram-negative bacteria, 9 Gram-positive bacteria and 4 strains of fungi and 5 strains of other pathogens. Statistics showed that the patient's age over 40 years old, hospitalization in spring and summer, glucocorticoid therapy, high intensity chemotherapy, neutrophil count, white blood cell count and hemoglobin content were the independent risk factors for infection after chemotherapy in AML patients (P<0.05).</p><p><b>CONCLUSION</b>The age of more than 40 years old, hospitalization in spring and summer, glucocorticoid therapy, high-intensity chemotherapy, white blood cell count, neutrophil count and hemoglobin content are the independent risk factors for infection after chemotherapy in the AML patients with the above-mentioned characteristics, they should be closely monitored, and chemotherapy intensity should be controled, so as to control the occurrence of infection; and in the event of infection, a timely powerful anti-infective treatment would be indispensable.</p>

Design of shelter-tent channel in mobile hospital / 医疗卫生装备

Objective To design a channel in the mobile hospital to solve the existing problems.Methods The technical form and characteristics of the existing channel were analyzed,and the requirements of the mobile hospital and channel shelter were considered comprehensively,then the selection of technical form and structure design of the channel shelter was explored from the aspects of airtightness,heat preservation and etc.The feasibility was verified by trial-manufacture and test.Results A shelter-tent channel was designed and the experiments showed its effectiveness when fulfilling the requirements of the mobile hospital.Conclusion The channel gains reasonable and feasible design,and has its performances meeting the desired requirements.

Design of shelter-tent channel in mobile hospital / 医疗卫生装备

Objective To design a channel in the mobile hospital to solve the existing problems.Methods The technical form and characteristics of the existing channel were analyzed,and the requirements of the mobile hospital and channel shelter were considered comprehensively,then the selection of technical form and structure design of the channel shelter was explored from the aspects of airtightness,heat preservation and etc.The feasibility was verified by trial-manufacture and test.Results A shelter-tent channel was designed and the experiments showed its effectiveness when fulfilling the requirements of the mobile hospital.Conclusion The channel gains reasonable and feasible design,and has its performances meeting the desired requirements.

Application of Integrative Medicines of TCM and WM Combined with Fast-track Surgery Concept in Perioperative Nursing in Colorectal Surgery / 昆明医科大学学报

Objective To study the clinical effect and significance of integrative medicines of TCM and WM combined with fast-track surgery concept on perioperative nursing in colorectal surgery.Methods One hundred and twenty patients with surgery were randomly divided into the observation group and the control group,60 cases in each group.The control group was treated with conventional nursing,while the observation group was treated with fast track surgery nursing of integrative medicines of TCM and WM.Results Bowel sound recovery time,anus exhaust time,defecation time,length of hospital stay and postoperative complications of observation group was significantly less than the control group (P＜0.05).Nursing total satisfaction of observation group was significantly higher than the control group (P＜0.05).Conclusion Integrative medicines of TCM and WM combined with fast-track surgery concept on perioperative nursing in colorectal surgery can reduce stress,speed up the recovery,reduce complications.So it is a safe and effective way of perioperative nursing,and worthy of clinical popularization and application.

Photonic generation of ultra-wideband signals by direct current modulation on SOA section of an SOA-integrated SGDBR laser.

Photonic ultra-wideband (UWB) pulses are generated by direct current modulation of a semiconductor optical amplifier (SOA) section of an SOA-integrated sampled grating distributed Bragg reflector (SGDBR) laser. Modulation responses of the SOA section of the laser are first simulated with a microwave equivalent circuit model. Simulated results show a resonance behavior indicating the possibility to generate UWB signals with complex shapes in the time domain. The UWB pulse generation is then experimentally demonstrated for different selected wavelength channels with an SOA-integrated SGDBR laser.

Preliminary investigation of the molecular mechanisms of imipenem-resistance in clinical isolates of Acinetobacter baumannii in Xi'an / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the molecular mechanism of carbapenem resistance in the clinical isolates of Acinetobacter baumannii from Xi'an and their profile of carbapenemase production.</p><p><b>METHODS</b>A total of 146 Acinetobacter baumannii strains were isolated from 6 general hospitals in Xi'an. Antimicrobial susceptibility test was performed for all the strains, followed by detection of imipenem resistance using E-test for metallo-beta-lactamase (MBL) and NaCl inhibition test for OXA type carbapenemase. Bla(OXA-23)and bla(OXA-58) were amplified by PCR, and the positive products were sequenced.</p><p><b>RESULTS</b>From the collected strains, 15 non-repetitive imipenem-resistant Acinetobacter baumannii strains were identified, among which 14 yielded negative results in E-test for MBL production. All the resistant strains showed increased sensitivity to imipenem after NaCl inhibition, suggesting the presence of carbapenemase production. Eleven of the strains harbored OXA -23 type gene and 1 harbored OXA -58 type gene. The concordance rate of the results by NaCl inhibition test and PCR was 85.7%.</p><p><b>CONCLUSIONS</b>Production of OXA-type carbapenemase is the most important reason for carbapenem resistance in Acinetobacter baumannii in Xi'an. The OXA-58 type gene is a novel carbapenemase genotype in China. NaCl inhibition test is a convenient and cost-effective method for detecting carbapenemase in Acinetobacter baumannii.</p>