Characterization of PLA/PBSeT Blends Prepared with Various Hexamethylene Diisocyanate Contents

Poly (lactic acid) (PLA) is the most widely available commercial bioplastic that is used in various medical and packaging applications and three-dimensional filaments. However, because neat PLA is brittle, it conventionally has been blended with ductile polymers and plasticizers. In this study, PLA was blended with the high-ductility biopolymer poly (butylene-sebacate–co–terephthalate) (PBSeT), and hexamethylene diisocyanate (HDI) was applied as a crosslinking compatibilizer to increase the miscibility between the two polymers. PLA (80%) and PBSeT (20%) were combined with various HDI contents in the range 0.1–1.0 parts-per-hundred rubber (phr) to prepare blends, and the resulting physical, thermal, and hydrolysis properties were analyzed. Fourier-transform infrared analysis confirmed that –NH–C=OO⁻ bonds had formed between the HDI and the other polymers and that the chemical bonding had influenced the thermal behavior. All the HDI-treated specimens showed tensile strengths and elongations higher than those of the control. In particular, the 0.3-phr-HDI specimen showed the highest elongation (exceeding 150%) and tensile strength. In addition, all the specimens were hydrolyzed under alkaline conditions, and all the HDI-treated specimens degraded faster than the neat PLA one.     

Effect of Copper Sulfate and Sulfuric Acid on Blind Hole Filling of HDI Circuit Boards by Electroplating

Here, in a certain high density interconnect (HDI) printed circuit board, the effect of copper sulfate and sulfuric acid on the filling effect of a blind hole with a certain diameter and depth was investigated by making a blind hole using a CO₂ laser drilling machine, filling the blind hole via electroplating by simulating the electroplating line in a Halin cell, and observing the cross-section of a micro blind hole after polishing using metallographic microscope, as well as the effect of hole filling, are evaluated. The results show that, under the conditions of a certain plating solution formula and electroplating parameters (current density and electroplating time), the sag degree decreases with the increase in the copper sulfate concentration. When the concentration of copper sulfate increases from 210 g/L to 225 g/L, the filling effect is good and the sag degree is about 0. However, with the increase in sulfuric acid concentration, the sag increases gradually. When the sulfuric acid concentration is 25–35 g/L, both the sag and copper coating thickness are in a small range. Under appropriate electroplating conditions, a better blind hole filling effect can be obtained. The volume of blind hole has a certain effect on the diffusion and exchange of copper sulfate and sulfuric acid, as well as on the concentration distribution of additives.     

ⅡB-ⅢD期黑色素瘤患者术后辅助PD-1抗体对比高剂量干扰素：一项回顾性队列研究

目的：探讨PD-1抗体对比高剂量干扰素在ⅡB-ⅢD期黑色素瘤患者术后辅助治疗中的疗效及安全性。方法：回顾性收集2013 年9 月至2022 年9 月期间在南京大学医学院附属楼医院收治的ⅡB-ⅢD期皮肤和肢端黑色素瘤患者的临床资料。所有患者术后均接受了高剂量干扰素（HDI）或PD-1 抗体辅助治疗。通过Kaplan-Meier 法行单因素生存分析并绘制生存曲线, Log-Rank 法分析评估组间无复发生存期（RFS）、无远处转移生存期（DMFS）以及总生存期（OS）差异是否有统计学意义,单因素和多因素Cox 回归分析判断影响患者预后的因素。结果：本研究共纳入91 例患者,中位随访时间为31.0个月。HDI 组和PD-1抗体组的mRFS 分别为29.2 个月和32.3 个月,差异无统计学意义[HR=0.90, 95%CI（0.50,1.64）;P=0.736]。HDI 组的mDMFS 和mOS分别为36.0个月和109.2个月,而PD-1抗体组均未达到（均P>0.05）。两组最常见的首次远处转移部位均是肺,并且在任何部位远处转移的发生率均无统计学差异（P>0.05）。通过单因素Cox 分析,相比于PD-1抗体,HDI 可以降低BRAFV600E/K突变的患者的远处转移风险[HR=10.03, 95%CI（1.10,91.35）;P=0.041]。亚组分析结果显示,在皮肤和肢端黑色素瘤中,HDI 组和PD-1单抗组的RFS 差异无统计学意义（均P>0.05）。HDI 组和PD-1抗体组不良反应发生率分别为83.3%和79.1%,多数为1或2级。两组均未发生与不良反应有关的死亡事件。结论：本研究中,PD-1抗体与HDI辅助治疗恶性黑色素瘤的临床疗效和安全性差异均无统计学意义;BRAFV600E/K突变的患者可能从HDI中获益更多;仍需大量前瞻性研究进一步探索亚洲人群黑色素瘤患者的最佳辅助治疗方案。     

ATL Ultramark 9HDI B超直流变换器故障原理及检修

本文介绍了ATL UM9HDI B超直流变换器的工作原理、常见故障及检修的方法。     

Outcome measurement in behavioral headache research: headache parameters and psychosocial outcomes

The experience of pain is complex and includes multiple dimensions or aspects, such as sensory and affective (among others). Headache includes not only pain, but also associated symptoms that can further diversify the relevant dimensions. Subjective ratings of head pain, sampled daily, have come to be regarded as the "gold standard" in behavioral headache research. Primary measures of headache include the attack frequency or headache days per month. Secondary measures of headache may include headache activity/index, headache duration, peak headache severity, and/or frequency of severe headaches per month. Secondary measures of disability and quality of life include Migraine Disability Assessment (MIDAS), Headache Impact Test (HIT), Headache Disability Inventory (HDI). Secondary nonheadache measures include medication consumption, psychiatric symptoms, stress and coping, treatment satisfaction and preference, side effects, and others. Researchers should include not only primary measures of headache, but also secondary measures, disability and quality of life, and nonheadache measures. All measures should be clearly defined and reported. A baseline period that is adequate for each measure needs inclusion and a minimum of 4 weeks is recommended for primary headache measures. Specific suggestions for future research directions are provided.     

A composite index to explain variations in poverty, health, nutritional status and standard of living: use of multivariate statistical methods

OBJECTIVES: To calculate the Human Development Index (HDI) and Human Poverty Index (HPI) of Indian states; to trace the indicators useful for finding variations in poverty; and to develop a composite index that may explain variations in poverty, health, nutritional status and standard of living. STUDY DESIGN: Cross-sectional study. METHODS: The HDI and HPI were calculated for different Indian states. A set of possible indicators varying between rich and poor states of India was identified with the use of discriminant function analysis. A composite index has been developed for measuring the standard of living of Indian states with the help of factor analysis. RESULTS: Demographic, socio-economic, health and dietary indicators play a major role in determining the real standard of living. Poverty, standard of living and human development depend on multiple factors. The existing indices, such as HDI and HPI, use income indicators to measure the standard of living, and do not take into account diet and nutritional status indicators. The proposed index was found to be more suitable for measuring the real standard of living and human development, as it is a comprehensive index of income and non-income indicators. Further validation may be carried out for different populations. CONCLUSIONS: Discriminant function analysis and factor analysis were used to assess health inequality and standard of living among Indian states. The proposed multi-dimensional index may provide a better picture of human development. Further work is of interest for other populations.     

Combined alveolitis and asthma due to hexamethylene diisocyanate (HDI), with demonstration of crossed respiratory and immunologic reactivities to diphenylmethane diisocyanate (MDI)

A worker exposed intermittently to hexamethylene diisocyanate (HDI) developed episodes of dyspnea, wheezing, and fever on working days. Complete lung function tests performed when the subject was asymptomatic were normal except for increased airway responsiveness to histamine, which significantly improved after a 3 wk period off work. At that time, specific inhalation challenges with HDI were carried out. After being exposed for 5 min, the subject developed general malaise, cough, fever, and leukocytosis, together with a mixed restrictive and obstructive breathing defect. We demonstrated a subsequent increase in airway hyperexcitability, which lasted for 2 mo. The subject was also challenged with diphenylmethane diisocyanate (MDI) for 15 min. A late obstructive reaction was documented. Increased levels of specific IgG antibodies against HDI-human serum albumin (HSA) and MDI-HSA were demonstrated.     

The guinea pig model of diisocyanate sensitization. I. Immunologic studies

Two strains of guinea pigs were parenterally immunized with well-characterized diisocyanate-protein conjugates. Hapten-specific IgE antibodies were detected in the sera of English short-hair strain guinea pigs immunized with either toluene diisocyanate-human serum albumin (TDI-HSA) or hexamethylene diisocyanate-HSA (HDI-HSA) when these sera were analyzed by the 168 hr passive cutaneous anaphylaxis (PCA) technique followed by intravenous challenges with conjugates of respective ligands coupled to an unrelated carrier protein, transferrin. IgG1 antibodies and precipitating antibodies were demonstrated in Hartley strain guinea pigs immunized with TDI/HDI-HSA conjugates. The hapten specificity of these antibodies was proved by PCA inhibition experiments and antibody absorption experiments. In the precipitating antibody system, this was further confirmed by immunoelectrophoretic analysis. Cross-reactivity between HDI and TDI was not observed in the PCA experiments. However, apparent cross-reactivity in the double gel diffusion experiments was due to new antigenic determinants formed by isocyanates after conjugation with proteins. It was therefore apparent that immune responses of guinea pigs immunized with protein conjugates of bifunctional isocyanates were heterogeneous and involved multiple specificities for hapten, carrier protein, and new antigenic determinants. It was postulated that the complex nature of the immune response generated by diisocyanate compounds in the guinea pig may also serve as a more appropriate model of isocyanate-induced human sensitivity reactions, which are known to involve diverse immunologic and nonimmunologic mechanisms.