My career in cytometry has so far had four phases: as a post doc from 1976 to 1978 in the pioneering flow cytometry group at Los Alamos Scientific Laboratory (LANL); a scientist from 1978 to 1987 with Ortho Instruments (later expanded to Ortho Diagnostic Systems) an early flow cytometer manufacturer; as a scientist with Becton Dickinson (BD) from 1987 to 2009; and as a retiree still engaged in cytometry since 2009. I have been fortunate that both companies I worked for encouraged scientific engagement and collaboration with the cytometry community and also encouraged publication of nonproprietary information. For me, many of those publications have been in Cytometry . The journal has been a valuable source of information as well as an opportunity to engage in the broader cytometry community on sometimes controversial topics. In the personal history that follows, I will include a thread concerning characterizing fluorescence detection performance that led to the idea of “Q and B" and continues to engage me today.

The journal Cytometry has been important to scientists in industry as well as their companies. In the early days of commercial flow cytometers, the primary value from my point of view was as a way for the cytometry community to learn about available products both through advertising in Cytometry and with publications from users of the instruments—especially how unique aspects of the instrument could be used or optimized. For the first seven issues of Cytometry , newly introduced Ortho flow cytometers were advertised on the prominent back cover page. The journal continues to be important in those ways. But as the field and the range of applications has expanded, Cytometry is an important source for new techniques or applications to guide marketing and product R&D.

My involvement with the Ortho flow cytometers advertised in 1980–1981 was minimal in those years as I was focused on a separate product, the Ortho Spectrum III, that was being developed for the clinical research and diagnostic market. Ortho was primarily a clinical company with a line of automated, light scatter‐based hematology analyzers. My time as a post doc at LANL was almost entirely focused on electrical impedance measurements of cells—especially using radio frequency currents to get information about the interior of cells. And that LANL work, completed by a LANL colleague after I started work at Ortho, resulted in my first publication in Cytometry (1). However, I was aware of the light scattering work that my post doc adviser, Gary Salzman, was doing, including a publication showing that using forward and right angle light scatter allowed discrimination of the major white blood cell types (lymphocytes, monocytes, and granulocytes). This bit of knowledge was essential for my first project at Ortho, which was to simplify the day‐long process of purifying lymphocytes and/or E‐rosetted T‐cells for immunofluorescent staining and analysis on Ortho Cytofluorografs. In the Fall of 1978, my supervisor, Peter Hansen, Ortho Instruments founder and president Lou Kamentsky and I traveled to Ortho Pharmaceuticals to learn about an application of a new thing called monoclonal antibody technology. Patrick Kung at Pharmaceuticals had developed monoclonal antibodies to subsets of lymphocytes. These OKT (OrthoKungTcell) antibodies were being used to study the human immune system including the reaction to immune modulators that were under investigation at pharmaceuticals. The OKT antibodies were initially for in‐house use but were also being supplied to collaborators. The problem was that the process for preparing and staining the cells took all day, while the time to run the sample on the flow cytometer (which had forward scatter and two colors of fluorescence of which only one color for fluorescein isothiocyanate (FITC) was used) took minutes. After hours of steps including ficoll isolation of mononuclear cells, removal of monocytes, sheep red cell E‐rosette separation of T‐ and B‐cells and indirect staining with a FITC‐conjugated second antibody for the OKT monoclonal, the samples could be run on the Cytofluorograf FC200 using forward scatter to identify cells from debris and green fluorescence to identify and count the stained cells. This was before the days of computerized flow cytometers and data analysis, so analog electronics were used to gate the cells using the forward scatter parameter and the green fluorescence signal was sent to a pulse height analyzer to obtain a histogram for analysis.

On the flight back home, Peter Hansen and I knew what we were going to try to do to simplify the process. It would be easy to just add the monoclonal antibody to whole blood, lyse the red cells, and use the forward and side scatter to identify the lymphocytes. That should be enough, since the E‐rosetting step did not seem essential given specificity of the antibodies. Back at Ortho, I did a quick modification to the Cytofluorograf FC200 I'd been given for my research. I changed the filter and dichroic mirror combination from green and red to green and blue (side scatter). I used the whole blood staining method, used the FC200 electronics to gate on the lymphocyte population in a forward scatter/side scatter oscilloscope dot plot, and displayed the green FITC fluorescence histogram on the pulse height analyzer for analysis. IT WORKED! Or so we two physicists thought. We were excited to give Patrick Kung the news and disappointed to hear that biology would not allow adding antibody to whole blood. There were too many complicating factors such as complement that could lyse cells. We should at least wash the blood first. But being naive about biology and probably a little stubborn, we kept pursuing the simple “add antibody to blood” approach. Eventually Patrick helped organize a study to compare the simple and more complicated methods. To his surprise and our relief, the simple method compared well with more complex methods that involved washing the blood sample before adding antibody. 1979 was a busy year. Indirect staining was replaced with FITC‐conjugated monoclonal antibodies. A patent was generated (2), a paper was written (3), and I was just in time to have the breadboard version of what was to become the Ortho Spectrum III modified so that it would run the scatter plus immunofluorescence assay as well as acridine orange stain assays of other blood cells.

In 1981 with the introduction of the Ortho Spectrum III, my career took a turn. Ortho Instruments became Ortho Diagnostic Systems with the OKT antibodies becoming a commercial product and part of the product line, and flow cytometry and hematology instruments being integrated into a much larger diagnostics company. The Spectrum III had three clinical tests (T‐cell count, fluorescent platelet count, and reticulocyte count) (4, 5) but with forward and side scatter and two colors of fluorescence could also be used as a research instrument. I became more engaged in exploring applications and learning about various clinical needs. From reading an introduction to immunology book during my lunch hours, I became involved in clinical discussions about problems with kidney transplants, possible therapeutic use of monoclonal antibodies, platelet disorders, and so on. There were numerous clinical collaborations (6, 7), but also time to try some riskier ideas. We demonstrated the now common method of using beads to do fluorescence immunoassays in a flow cytometer (8) and tried a novel and unsuccessful “negative fluorescence” approach to measuring red cell volume using displacement of fluorescence solution in a flow cytometer (9).

I began being concerned about how to verify that a flow cytometer had adequate sensitivity to accurately identify dimly fluorescent cells and what standards should be used. There was not much consensus in the early‐ and mid‐1980s, but there were scientists in both industry and academia who had an informal interest group on this topic. At Ortho, we developed a standardization concept called Fluorotrol that was a mix of unstained calf thymocyte nuclei and nuclei stained at dim and moderate levels with FITC. This was an early attempt to have a material that could be used to standardize fluorescent gain settings and quantitatively measure resolution of dim staining (10). We also began working on a new hematology‐immunology system that would be much more capable, less costly and replace both the existing Ortho hematology instruments and the Spectrum III. To make the immunofluorescence analyzer less costly using then available reagents and lasers, we arrived at a scanning cytometer that used a red helium neon laser (11, 12). The new system got to the prototype stage before the parent company, Johnson & Johnson, decided to get out of the hematology and flow cytometry business in 1987.

Luckily, I was able to get a job with BD in the R&D group and enjoyed 22 years there. The first years with BD were focused mostly on instrumentation—initially helping to develop a simple system, the FACSCount, dedicated to CD4 counting in the less developed world. Some FACSCount details are in a later review of BD contributions to CD4 counting (13). There was also opportunity in the early 1990's to manage a small group to explore alternative technologies, which included fluorescence lifetime flow cytometry (14) and the use of air cooled lasers to do chromosome karyotyping (15). The FACSCalibur project in the mid‐1990s was intended as a quick upgrade to a fourth color on the FACScan. The approach to use APC and a second red, diode laser to produce the fourth color added complexity and significant analog electronics innovation compared to just adding a fourth color from the blue laser. But the approach has stood the test of time and provided a good understanding of what to do and not do in future multilaser products.

The FACSCalibur project also gave me an opportunity to pursue new approaches to characterizing and specifying performance. Not all those ideas made it to the end of product release but were further pursued with Eric Chase from CYTEK Development, who was then working with me as a consultant. Better ways to characterize and specify fluorescence performance had been an active topic at the annual Cytometry Development Workshop for several years, and Jim Wood, then at Beckman Coulter, and I were among the vocal proponents for physically relevant, quantitative measures. The workshop meeting in October 1997 gave Jim Wood and me the responsibility to write up a protocol for a method, get it published, and also write an article for Cytometry. The motivation for the Cytometry article was further motivated by an invitation to submit articles for a special 1998 Cytometry issue on Quantitative Fluorescence Cytometry: An Emerging Consensus. In that issue, an article by Eric Chase and me provided the fundamental basis and experimental results for characterizing fluorescence sensitivity on the basis of detection efficiency (Q) and background light (B) (16). And Jim Wood and I got the OK from our respective managements at Beckman Coulter and BD to co‐author an overview on why a new paradigm for assessing fluorescence sensitivity was needed (17). In that same issue was an article on a project led by Ken Davis at BD to determine antibody‐binding capacity for CD4 on lymphocytes. The article also rigorously established the scientific basis for assigning the number of R‐phycoerythrin molecules to calibration beads used for BD's QuantiBRITE system (18). For some reason, it took a while to get the Q&B protocols written and published (19).

Informal discussions among scientists concerned about making flow cytometry fluorescence measurements quantitative and standardized led to a workshop involving participants from International Society for Advancement of Cytomtery (ISAC) and National Institute of Standards and Technology (NIST), with the outcome that NIST was encouraged to establish a program to define fluorescent standards and make available reference standards for industry. With some equipment donations from companies, including flow cell, optics and data acquisition from BD, Adofas Gaigals at NIST assembled a reference flow cytometer as part of a system to assign molecules of equivalent soluble fluorophore (MESF) to beads. Combined with a custom, laser based spectrofluorometer, Adolfas and Lili Wang developed the NIST protocol for assignment of MESF values to beads. Working with Adolfas and Lili has been a great learning experience. The NIST standardization effort continues and has expanded under Lili Wang's direction to equivalent reference fluorophores (ERF) as a practical extension of MESF (20).

The last decade of my BD career was mostly spent helping design and evaluate new instruments and technologies. But the sensitivity and instrument performance characterization bug kept biting me. After a complaint at a workshop on instrument standardization and performance characterization that too many different beads had to be run and kept track of, I promoted and worked on a concept of using only three beads (bright, mid‐bright and dim and fluorescing in those intensity ranges in all colors). The result after more absolutely necessary effort than I had imagined, was BD's CS&T system—not quite perfect as true intensity standards, but a practical, automatable system that can be used to define instrument performance requirements in product development, carry those requirements to manufacturing testing specifications and customer acceptance criteria, and assist service in troubleshooting.

Since retiring in 2009, Cytometry has helped keep me informed about the exciting developments in the field and kept me connected to a scientific community I care about and respect. And somehow every few years, I have been involved in a collaboration on standardization or instrument performance characterization that has resulted in a publication—usually in Cytometry (21-26). Maybe this one will not be the last.

Finally, I would like to recognize colleagues that have not been mentioned above who have been essential to my journey in cytometry at BD. Thank you Diether Recktenwald, Joe Trotter, and Willem Stokdijk. And thanks to all of you in the cytometry community—especially Ming Yan—who have kept me engaged since retirement.

迄今为止，我在细胞计数方面的职业经历了四个阶段：1976 年至 1978 年在洛斯阿拉莫斯科学实验室 (LANL) 的开创性流式细胞术小组担任博士后；1978 年至 1987 年的科学家，Ortho Instruments（后来扩展为 Ortho Diagnostic Systems）是一家早期的流式细胞仪制造商；1987 年至 2009 年在 Becton Dickinson (BD) 担任科学家；作为一名退休人员，自 2009 年以来一直从事细胞计数。我很幸运，我工作的两家公司都鼓励与细​​胞计数界的科学参与和合作，并鼓励发布非专有信息。对我来说，这些出版物中有许多是关于细胞学的. 该杂志一直是宝贵的信息来源，也是参与更广泛的细胞学界讨论有时有争议的话题的机会。在接下来的个人经历中，我将包括一个关于表征荧光检测性能的主题，该主题导致了“Q 和 B”的想法，并在今天继续吸引我。

Cytometry杂志对工业界的科学家及其公司都很重要。在商业流式细胞仪的早期，从我的观点来看，主要价值是作为一种让流式细胞仪社区通过流式细胞仪广告和仪器用户的出版物了解可用产品的方式——尤其是流式细胞仪的独特方面可以使用或优化仪器。对于Cytometry的前七期，新推出的 Ortho 流式细胞仪在显着的封底页上做了广告。该期刊在这些方面仍然很重要。但随着领域和应用范围的扩大，细胞计数 是指导营销和产品研发的新技术或应用的重要来源。

在那些年里，我对 1980 年至 1981 年宣传的 Ortho 流式细胞仪的参与很少，因为我专注于为临床研究和诊断市场开发的单独产品 Ortho Spectrum III。Ortho 主要是一家临床公司，拥有一系列基于光散射的自动化血液学分析仪。我在 LANL 做博士后的时间几乎完全专注于细胞的电阻抗测量——尤其是使用射频电流来获取有关细胞内部的信息。在我开始在 Ortho 工作后，由 LANL 同事完成的 LANL 工作导致我在细胞计量学上发表了第一篇文章（1）。然而，我知道我的博士后顾问 Gary Salzman 正在做的光散射工作，包括一份出版物表明使用前向和直角光散射可以区分主要的白细胞类型（淋巴细胞、单核细胞和粒细胞） ）。这些知识对于我在 Ortho 的第一个项目至关重要，该项目旨在简化纯化淋巴细胞和/或 E 玫瑰花结 T 细胞以对 Ortho Cytofluorografs 进行免疫荧光染色和分析的全天过程。1978 年秋天，我的上司 Peter Hansen、Ortho Instruments 创始人兼总裁 Lou Kamentsky 和我前往 Ortho Pharmaceuticals，了解一种叫做单克隆抗体技术的新事物的应用。制药公司的 Patrick Kung 开发了针对淋巴细胞亚群的单克隆抗体。这些 OKT (OrthoKungTcell) 抗体被用于研究人类免疫系统，包括对正在研究中的药物免疫调节剂的反应。OKT 抗体最初供内部使用，但也提供给合作者。问题是制备和染色细胞的过程需要一整天，而在流式细胞仪上运行样品的时间（具有前向散射和两种颜色的荧光，其中仅使用一种颜色的异硫氰酸荧光素 (FITC) ) 花了几分钟。经过数小时的步骤，包括单核细胞的 ficoll 分离、单核细胞的去除、T 细胞和 B 细胞的绵羊红细胞 E 玫瑰花环分离以及用 FITC 偶联的二抗间接染色 OKT 单克隆抗体，样品可以在 Cytofluorograf FC200 上运行，使用前向散射从碎片中识别细胞，并使用绿色荧光来识别和计数染色细胞。这是在计算机化流式细胞仪和数据分析出现之前，因此使用模拟电子设备使用前向散射参数对细胞进行门控，并将绿色荧光信号发送到脉冲高度分析仪以获得直方图进行分析。

在回家的航班上，彼得汉森和我知道我们将尝试做些什么来简化流程。只需将单克隆抗体添加到全血中，裂解红细胞，然后使用前向和侧向散射来识别淋巴细胞就很容易了。这应该足够了，因为考虑到抗体的特异性，E-玫瑰花设置步骤似乎不是必需的。回到 Ortho，我对我的研究使用的 Cytofluorograf FC200 进行了快速修改。我将滤镜和分色镜组合从绿色和红色更改为绿色和蓝色（侧向散射）。我使用全血染色方法，使用 FC200 电子设备在前向散射/侧向散射示波器点图中对淋巴细胞群进行门控，并在脉冲高度分析仪上显示绿色 FITC 荧光直方图以进行分析。它奏效了！或者我们两个物理学家是这么想的。我们很高兴将这个消息告诉 Patrick Kung，但听到生物学不允许在全血中添加抗体，我们感到很失望。有太多的复杂因素，例如可以裂解细胞的补体。我们至少应该先把血洗干净。但由于对生物学幼稚且可能有点固执，我们一直在追求简单的“在血液中添加抗体”的方法。最终帕特里克帮助组织了一项研究来比较简单和更复杂的方法。令他惊讶和欣慰的是，这种简单的方法与更复杂的方法（在添加抗体之前清洗血样）相比效果很好。1979年是忙碌的一年。间接染色被 FITC 偶联的单克隆抗体取代。产生了一项专利（我们很高兴将这个消息告诉 Patrick Kung，但听到生物学不允许在全血中添加抗体，我们感到很失望。有太多的复杂因素，例如可以裂解细胞的补体。我们至少应该先把血洗干净。但由于对生物学幼稚且可能有点固执，我们一直在追求简单的“在血液中添加抗体”的方法。最终帕特里克帮助组织了一项研究来比较简单和更复杂的方法。令他惊讶和欣慰的是，这种简单的方法与更复杂的方法（在添加抗体之前清洗血样）相比效果很好。1979年是忙碌的一年。间接染色被 FITC 偶联的单克隆抗体取代。产生了一项专利（我们很高兴将这个消息告诉 Patrick Kung，但听到生物学不允许在全血中添加抗体，我们感到很失望。有太多的复杂因素，例如可以裂解细胞的补体。我们至少应该先把血洗干净。但由于对生物学幼稚且可能有点固执，我们一直在追求简单的“在血液中添加抗体”的方法。最终帕特里克帮助组织了一项研究来比较简单和更复杂的方法。令他惊讶和欣慰的是，这种简单的方法与更复杂的方法（在添加抗体之前清洗血样）相比效果很好。1979年是忙碌的一年。间接染色被 FITC 偶联的单克隆抗体取代。产生了一项专利（有太多的复杂因素，例如可以裂解细胞的补体。我们至少应该先把血洗干净。但由于对生物学幼稚且可能有点固执，我们一直在追求简单的“在血液中添加抗体”的方法。最终帕特里克帮助组织了一项研究来比较简单和更复杂的方法。令他惊讶和欣慰的是，这种简单的方法与更复杂的方法（在添加抗体之前清洗血样）相比效果很好。1979年是忙碌的一年。间接染色被 FITC 偶联的单克隆抗体取代。产生了一项专利（有太多的复杂因素，例如可以裂解细胞的补体。我们至少应该先把血洗干净。但由于对生物学幼稚且可能有点固执，我们一直在追求简单的“在血液中添加抗体”的方法。最终帕特里克帮助组织了一项研究来比较简单和更复杂的方法。令他惊讶和欣慰的是，这种简单的方法与更复杂的方法（在添加抗体之前清洗血样）相比效果很好。1979年是忙碌的一年。间接染色被 FITC 偶联的单克隆抗体取代。产生了一项专利（最终帕特里克帮助组织了一项研究来比较简单和更复杂的方法。令他惊讶和欣慰的是，这种简单的方法与更复杂的方法（在添加抗体之前清洗血样）相比效果很好。1979年是忙碌的一年。间接染色被 FITC 偶联的单克隆抗体取代。产生了一项专利（最终帕特里克帮助组织了一项研究来比较简单和更复杂的方法。令他惊讶和欣慰的是，这种简单的方法与更复杂的方法（在添加抗体之前清洗血样）相比效果很好。1979年是忙碌的一年。间接染色被 FITC 偶联的单克隆抗体取代。产生了一项专利（2），写了一篇论文（3），我及时修改了将成为 Ortho Spectrum III 的面包板版本，以便它可以运行散射加免疫荧光测定以及吖啶橙染色测定其他血细胞。

1981 年，随着 Ortho Spectrum III 的推出，我的职业生涯发生了转折。Ortho Instruments 成为 Ortho Diagnostic Systems，OKT 抗体成为商业产品和产品线的一部分，流式细胞仪和血液学仪器被整合到一个更大的诊断公司中。Spectrum III 进行了三项临床测试（T 细胞计数、荧光血小板计数和网织红细胞计数）（4、5) 但具有前向和侧向散射以及两种颜色的荧光也可以用作研究仪器。我更加专注于探索应用和了解各种临床需求。通过在午餐时间阅读免疫学入门书，我开始参与有关肾移植问题、单克隆抗体的可能治疗用途、血小板疾病等的临床讨论。有许多临床合作 ( 6, 7 )，但也有时间尝试一些更冒险的想法。我们展示了目前使用微珠在流式细胞仪中进行荧光免疫测定的常用方法 ( 8) 并尝试了一种新颖且不成功的“负荧光”方法，通过置换流式细胞仪中的荧光溶液来测量红细胞体积 ( 9 )。

我开始担心如何验证流式细胞仪是否具有足够的灵敏度来准确识别微弱荧光细胞以及应该使用什么标准。在 1980 年代早期和中期没有太多共识，但工业界和学术界的科学家都在这个话题上建立了一个非正式的兴趣小组。在 Ortho，我们开发了一种称为 Fluorotrol 的标准化概念，它是未染色的小牛胸腺细胞核和用 FITC 以暗淡和中等水平染色的细胞核的混合物。这是获得一种材料的早期尝试，该材料可用于标准化荧光增益设置并定量测量暗染色的分辨率（10）。我们还开始研究一种新的血液学-免疫学系统，该系统功能更强大、成本更低，可替代现有的 Ortho 血液学仪器和 Spectrum III。为了使用当时可用的试剂和激光降低免疫荧光分析仪的成本，我们设计了一种使用红色氦氖激光的扫描细胞仪 ( 11, 12 )。在母公司强生公司于 1987 年决定退出血液学和流式细胞术业务之前，新系统已进入原型阶段。

幸运的是，我在 BD 的研发部门找到了一份工作，并在那里度过了 22 年。与 BD 合作的最初几年主要专注于仪器——最初帮助开发一个简单的系统 FACSCount，专用于欠发达国家的 CD4 计数。稍后对 BD 对 CD4 计数的贡献的评论中提供了一些 FACSCount 详细信息 ( 13 )。1990 年代初期也有机会管理一个小组来探索替代技术，其中包括荧光寿命流式细胞术 ( 14 ) 和使用空气冷却激光器进行染色体核型分析 ( 15)）。1990 年代中期的 FACSCalibur 项目旨在快速升级到 FACScan 上的第四种颜色。与仅添加来自蓝色激光的第四种颜色相比，使用 APC 和第二个红色二极管激光器产生第四种颜色的方法增加了复杂性和显着的模拟电子创新。但该方法经受住了时间的考验，并提供了对未来多激光产品中该做什么和不该做什么的很好的理解。

FACSCalibur 项目也让我有机会寻求新的方法来表征和指定性能。并非所有这些想法都在产品发布结束时得以实现，但后来由 CYTEK Development 的 Eric Chase 进一步追求，他当时作为顾问与我一起工作。几年来，更好地表征和指定荧光性能的方法一直是年度细胞计量学开发研讨会的一个活跃话题，而当时在贝克曼库尔特工作的吉姆伍德和我是物理相关定量测量的声音支持者之一。1997 年 10 月的研讨会会议让 Jim Wood 和我负责为一种方法编写一个协议，并发布它，并为细胞计数写一篇文章。细胞学的动机这篇文章的进一步动机是受邀为 1998年关于定量荧光细胞术的特殊细胞术问题提交文章：一种新兴的共识。在那个问题上，Eric Chase 和我的一篇文章提供了基于检测效率 (Q) 和背景光 (B) 表征荧光灵敏度的基本依据和实验结果 ( 16 )。吉姆伍德和我得到了贝克曼库尔特和 BD 各自管理层的同意，他们共同撰写了一篇关于为什么需要评估荧光灵敏度的新范式的概述（17）。在同一期中还有一篇关于由 BD 的 Ken Davis 领导的项目的文章，该项目旨在确定淋巴细胞上 CD4 的抗体结合能力。该文章还严格建立了将 R-藻红蛋白分子数量分配给用于 BD 的 QuantiBRITE 系统的校准珠的科学依据 ( 18 )。出于某种原因，编写和发布 Q&B 协议需要一段时间 ( 19 )。

关注流式细胞术荧光测量定量和标准化的科学家之间的非正式讨论导致了一个研讨会，参与者来自国际细胞术促进会 (ISAC) 和美国国家标准与技术研究所 (NIST)，结果鼓励 NIST 建立一个定义荧光标准并为工业提供参考标准的程序。通过来自公司的一些设备捐赠，包括来自 BD 的流动池、光学器件和数据采集，NIST 的 Adofas Gaigals 组装了一个参考流式细胞仪，作为系统的一部分，将等效可溶性荧光团 (MESF) 的分子分配给珠子。结合定制的基于激光的分光荧光计，Adolfas 和 Lili Wang 开发了 NIST 协议，用于将 MESF 值分配给珠子。与 Adolfas 和 Lili 一起工作是一次很棒的学习经历。NIST 标准化工作仍在继续，并在 Lili Wang 的指导下扩展到等效参考荧光团 (ERF)，作为 MESF 的实际扩展（20 )。

我 BD 职业生涯的最后十年主要用于帮助设计和评估新仪器和技术。但是灵敏度和仪器性能表征错误一直困扰着我。在仪器标准化和性能表征研讨会上抱怨必须运行和跟踪太多不同的珠子后，我提出并致力于仅使用三种珠子的概念（明亮、中亮、暗淡和荧光）所有颜色的强度范围）。经过比我想象的更绝对必要的努力，结果是 BD 的 CS&T 系统——作为真正的强度标准并不完美，而是一个实用的、可自动化的系统，可用于定义产品开发中的仪器性能要求，

自 2009 年退休以来，Cytometry一直帮助我了解该领域令人兴奋的发展，并使我与我关心和尊重的科学界保持联系。不知何故，每隔几年，我就参与了标准化或仪器性能表征方面的合作，结果发表了一篇文章——通常是在细胞计量学上( 21-26 )。也许这不会是最后一次。

最后，我要感谢上面没有提到的同事，他们对我在 BD 的细胞术之旅至关重要。感谢 Diether Recktenwald、Joe Trotter 和 Willem Stokdijk。还要感谢细胞计数界的所有人——尤其是 Ming Yan——自退休以来一直让我参与其中。