Máximo Valentinuzzi (1907–1985): Perhaps the First Latin American Biophysicist, Biomathematician, and Bioengineer
My father was always studying, full of dedication and encouragement, my mother always pushed me to study, later on my wife, during our 55 years together, backed me up to study while she also kept studying … all three of them, unrelentingly, almost stubbornly, but always joyfully, even in the worst troubled moments … What else could I do? Besides, and more importantly, isn’t it nice, good, rewarding, liberating, to fill the spirit while looking up into the skies, away from the worldly thorns and its forever crazy self-destructing search of money and power? Finally, and most relevant, a full spirit may alleviate human pains.
Is it right for a son to write about his father? Some people may object to it because all kinds of polarizations and pitfalls cover the way to a final readable and acceptable piece. Father–son relationships have historically been a psychological subject of concern. It should be said that we had better speak of parent–child relationships, for the mother often plays a significant if not a central role in her son’s or daughter’s life.
The musicologist Maynard Solomon maintains that Leopold, Wolfgang Amadeus Mozart’s father, enjoyed the reflections of his glorious child’s talents but exploited the boy for material gains. Nonetheless, for a long time, he was tremendously important and influential in Wolfgang’s life (1756–1791). Another remarkable example can be found in Ludwig van Beethoven (1770–1827). His father, Johann, was an unnoticed musician at the court of Bonn, but he detected his son’s gift for music at an early age and taught him as much as he could, envisioning and dreaming of a new Mozart (which he was, indeed, and perhaps even more). Unfortunately, his father’s alcoholism stood in the way, tearing them apart. Hermann and Franz Kafka (1883–1924) place us also in front of a complex father–son link, commonly described as big, loud, impulsive, and authoritarian, so much that Franz, in his “Letter to My Father,” openly expressed his strained feelings and emotions toward his father .
Closer to our times, and more related to the field usually dealt with in this column, Renate Forssmann-Falck, a German-born psychiatrist who settled in the United States in 1978, speaks dearly of her father, Werner Forssman, a Nobel Prize cowinner in 1956 for his achievements in human cardiac catheterization , . Other such examples abound in the literature, some more or less intricate, some more or less attractive, and some showing clear rejection (as in Kafka’s case mentioned above) or revered deep love and respect (as when reading about the rather strange and moving relationship between Galileo Galilei and his daughter Virginia, who became Suor Maria Celeste at a very early age ).
Yes, the parent–child relationship is so significant that it may forever affect the latter’s future, from absolute disaster (as when the parent vanishes, for example) to the highest levels of success (as when they offer true full orientation and love). A most remarkable case to recall falls on the Curie-Slodowska family.
Irène Joliot-Curie (1897–1956) was the daughter of Marie Slodowska and Pierre Curie (1859–1906). Jointly with her husband, Jean Frédéric Joliot (1900–1958), she received the Nobel Prize in chemistry in 1935. Her mother, Marie (1867–1934), shared the 1903 Nobel Prize in physics with her husband Pierre and physicist Henri Becquerel (1852–1908) and was thereafter the sole winner of the 1911 Nobel Prize in chemistry. Thus, she became the first woman to win a Nobel Prize, the only woman to win in two fields (so far), and the only person to win in two fields of science. Pierre and Marie were loving parents. After Pierre’s tragic demise, Marie took over the role of father as well, dearly caring for her children. All of this made the Curies the family with the most Nobel laureates to date. Both children of the Joliot-Curies, Hélène and Pierre, were also highly respected scientists. Marie never lost her Polish identity, teaching her daughters the Polish language and taking them on visits to Poland. She named the first chemical element she discovered, isolated in 1898, in honor of her native land: polonium. Her death was due to aplastic anemia brought on by exposure to radiation.
My father was a scientist, and I followed a similar path, sometimes on superimposed subjects, sometimes together. Obviously, his influence was important. Our relationship was good, friendly, and frequently of a teacher–student kind. No doubt, he was my first and, in many respects, my best teacher in science, human philosophy, and daily life affairs; sometimes, however, especially when I was older, it was stained with some hard clashes, but we recovered and came back to being on good terms. Since I inherited most of the books, papers, documents, and letters collected over the years by my father plus the many experiences and stories we went through together, which are still clear in my memory, I intend here to show him as being perhaps the first scientist who, in Latin America, worked hard to establish biophysics and biomathematics, even unknowingly acting as an early bioengineer.
Birth, Childhood, and Teenage Years in Río Cuarto (1907–1926)
The first Spaniards reached, in 1573, the area of what now is the city of Río Cuarto (for this is the current name of the river that traverses it) in the southern region of the Province of Córdoba, Central Argentina. Surrounded by fertile lands, soon many cattle breeders settled there under the domain of a convent, Santa Catalina. Its rule produced an accelerated social and economic development that lasted for a long time. The Indians (the Araucanos and Ranqueles), who were all rather hostile, were attracted by such prosperity and started to attack ranches, stealing animals, ransacking, and abducting women and children. A few protective forts were built and, in 1784, Vice-Roy Rafael de Sobremonte (1745–1827) founded the Villa de la Concepción del Río Cuarto but failed to fully end the Indian assaults, which led to considerable depopulation. Nonetheless, the small villa survived and slowly progressed in relative solitude.
The year 1880 marked the beginning of a heavy Italian and Spanish immigration into Argentina, bringing new blood to the country. Río Cuarto became one of the many final destinations, where these people mainly settled down as farmers. Máximo Valentinuzzi I (1877–1953) was born in Pavia di Udine, which is in northern Italy. He was a carriage blacksmith and carpenter by profession. Because his parents emigrated from Europe, Máximo I arrived in Río Cuarto at a rather young age to make a new life. He soon met and married Clementina Donda (1875–1953) in 1902 (Figure 1), who was also born in the Friule region of Italy but was of Austrian nationality because that region was part of the Austro-Hungarian Empire in those days. In the early 20th century, Argentina held fewer than five million inhabitants (versus the more than 40 million today). The city of Río Cuarto, now with 160,000 people, if we accept that the same ratio of 5/40 was kept, must have had a population in the order of 20,000 at most. Everything was just beginning, promising but surrounded by uncertainties too.
My grandma, Clementina, then 32, could not conceive a child for five years, for which reason the couple was very concerned. They consulted with physicians and midwives, deciding in the end to make a pilgrimage to the Virgen de La Reducción, a highly devoted virgin whose image is placed in the town of La Reducción, which is about 50 km from Río Cuarto. They prayed, and, low and behold, nine months later, my father, Máximo II (1907–1985), was born in a beautiful house located on General Paz Street with a stone threshold at its entrance displaying my grandfather’s initials, M.V. I recall seeing it when visiting the place as a child with my parents. That house, according to the manuscript notes left by my father and my memories of family talks, brought pride and joy and, soon thereafter, intense painful chagrin due to the poor administration my grandfather made of his well-installed blacksmith–carpenter workshop using a bank mortgage loan. The house was repossessed and lost, starting a family downslide to poverty never to be recovered. My grandfather never stopped working hard until literally the last minute of his life; he was very generous and honest but could not make up for the devastating loss. Obviously, he was fully unable to take care of his monies and responsibilities, while Clementina, without any education, turned into a washerwoman and raised almost single-handedly four children (often helped by her only sister, a niece, and her mother, all who lived in a nearby small town, Sampacho) and always encouraged them to study, study, study. The day she died, in 1953, bedridden by a number of pathologies and with obvious respiratory distress, I visited her a couple of hours before and, holding my hand, she asked me if that day I had attended classes at the engineering school. My father always revered the penetrating chlorine smell of his mother’s hands engraved in his memory.
During elementary school, after facing great difficulties with arithmetic and reading, Manuela Cabral, a serious and stern, well-prepared and intelligent teacher of the sixth grade, opened a window of fresh air to Máximo II’s mind, transforming him into a math lover and an avid reader. Several famous titles passed quickly through his hands [Figure 2(a)], such as the Youth of Henry IVth, by Pierre Alexis, Viscount Ponson du Terrail (1829–1871). In high school, his French professor, Adrián Etchecopar, fluent in several languages, had an extraordinary influence, so much so that Máximo became a language fanatic and decided to learn at least 50 languages. He couldn’t reach that target figure but managed with quite a few: French, Italian, Portuguese, German, English, Esperanto, Russian, and some Latin and Greek; Furlan he readily understood as it was the family language of his parents. He was always searching for the etymology of words and learned most of the languages by himself. Clear in my memory are his frequent explanations of terms, slangs, idioms, linguistic relationships, etc. At age 15, he read Phylogeny, a long, difficult book authored by the Argentine naturalist Florentino Ameghino (1854–1911). This book led him to explore the riversides of the Río Cuarto, where he found a fossil glyptodont bone, which, many years later, was donated to the Archeological and Anthropological Museum of Buenos Aires “Bernardino Rivadavia,” where its classification was confirmed.
The year 1926 was ending, and his fifth and last year in the Río Cuarto National High School was also getting close to the end. Máximo, as the best pupil (who had never missed a day of classes), was designated by the rector, Dr. Ricardo Machado, another great teacher, to offer a farewell talk dealing with the structure of matter and the modern atomic theories (he already had a prestige within the school because of his many times manifested scientific inclinations). Present at the talk was the National Inspector of Mathematics, Prof. José María Igartúa, an engineer. That conference became a momentous event for the school and for the city, even with articles in the local newspaper; Prof. Igartúa advised my father to take the entrance examination at the University of Buenos Aires rather than at the University of Córdoba, as his plan was.
Medical Student in Buenos Aires City (1927–1932)
And so he moved to Buenos Aires early in 1927 to start medicine, being 19 years old and using the savings he had painfully collected over the previous five years by offering classes to younger students in math, physics, French, and other subjects, as his eagerness for knowledge steadily grew. He had also wanted to get in math courses, but the medical school demands were tough and would not allow him enough time.
As it could be expected, his savings did not last too long and were depleted at one point. This signaled the beginning of a period of hardship, and even sheer hunger, with mounting debts here and there and difficulties to repay through the occasional help from his father or mother (as they were also hit by privation), momentary short jobs, and translations for medical journals (his language knowledge being an enormously handy tool). On top of that personal and family situation already with a sad history, the crisis of those times reached almost every home, producing unemployment and thousands of indigents essentially the world over. A streetcar ticket in Buenos Aires was 10 cents of a peso, the price of a liter of milk was 10 cents or less, a university student teaching assistant earned in the order of 70 pesos per month, and 300–400 pesos was deemed a good monthly income, all this when US$1 was equal to 2.40 Argentine pesos. Máximo used to buy one or two eggs, a piece of bread, and a few tangerines for less than 1 peso, keeping the tangerine peel to eat with bread later as dinner. He continued with that custom (tangerine peels with bread) for many years as a kind of dessert or, perhaps, as a condescending remembrance. I well recall that, also trying the taste myself but not really convinced. However, despite these difficulties, his studies were a strong driving force, as if spurting from a deep biological instinct (as he literally wrote in his notes).
Physician, Biophysicist, and Biomathematician (1933–1957)
After that saga, Máximo graduated as a medical doctor in December 1932, at age 25. He had married Emma Lucía Mazzulli (1909–2000) in June 1931, who was of southern Italian origin, and I was born in February 1932. However, the condition of neediness continued [Figure 2(b)]. Times were very hard, and his modest incomes came from different odd jobs, all related to medicine, including a somewhat more stable one of practicing physician between 1931 and 1933 at the Institute of Maternity in Buenos Aires (Figure 3). The latter position set the beginning of a medical career at that institute that lasted until 1952 and where he held several positions of growing responsibilty. Máximo loved that hospital (well set and of strict discipline), although disagreeing deeply with the discriminatory social system it was set upon. He brought to it and encouraged in it fresh ideas (he encouraged the use of statistics, opened a small research laboratory, and organized seminars) and gained an enormous amount of experience in obstetrics and gynecology while increasing his innate profound respect for life, especially for the life a woman’s uterus represents. Someone hinted once that the Holy Grail never existed (or it was a common metal cup lost soon after the Last Supper); it dwells and abides instead in each woman’s uterus all over the world, a wonderful and touching concept that many in our troubled world, who often mercilessly offend women and womanliness, should learn about and keep in mind. Figure 4 shows the first paragraph of handwritten notes scribbled probably in 1931 or 1932; it says:
Obstetrics Philosophical Principles
Obstetrics is the art of life par excellence. It is united unbreakably and by nature to the woman and to the child; it is the discipline that scientifically orients and cooperates to human procreation. Its definition is brief and eloquent: ars vitae.
Alberto Peralta Ramos, director of the Institute and a highly respected specialist, was his main teacher in that medical specialty; Máximo became Ramos’ personal librarian at his residence in a fancy area of Buenos Aires, going there twice a week. In addition, Máximo also opened a small private practice, which was characterized by charging almost nothing, or nothing at all, when he realized his patient was in need, his socialist ideology creeping up as fresh as ever, as clearly expressed in many documents and articles from his student years in medical school; thus, the family income never reached the end of the month. Another rather long document written in 1932 or 1933 (Figure 5) refers to the contradictions between our current civilization and human life by stating:
Our civilization contradicts in fact the conservation and development of human life, which must be integral. For that reason, it is absurd. Shouts and men protesting actions, who crave for better conditions, must energetically rise against this absurd civilization, bloodily contradictory.
But mathematics and physics, as manifested long before in his life, were also strong attractors for him, so, in 1935, Máximo registered as a student in the school of mathematics and physics of the University of Buenos Aires, graduating with a licenciate degree in 1942 after arduous years of simultaneously dealing with the demanding hospital duties, courses and examinations, family responsibilities, and a constant economic shortage. That year, Silvia Lucía (my sister) was born.
In 1957, Máximo moved to the United States with a position of research associate at the Committee on Mathematical Biology at the University of Chicago. The committee was led by Nicholas Rashevsky, with whom Máximo had much earlier established regular correspondence and exchanged ideas. However, before moving to the United States, having left the Institute of Maternity in 1952, he held several positions in different Argentine institutions. His most important position was as the director of the Laboratory of Biophysics in a research institute sponsored by and placed within the nice building of the National Academy of Medicine in Buenos Aires , along with a professorship of biophysics at the Universidad Nacional del Litoral, in the city of Rosario (300 km from Buenos Aires), where he commuted by train every week (Figure 6). Those were difficult years plagued with political upheaval, which, for him, in the end, as well as for others in academia, meant losing their jobs. Máximo left behind long years of scientific and financial frustrations, which are discussed in –.
The Chicago Period (1957–1971)
The Chicago period was, without a doubt, the happiest and most productive time of his life until retirement (Figure 7), with several trips to Argentina and even sharing a joint last position at the National Institute of Microbiology of Buenos Aires. Soon thereafter, in the 1960s, he obtained American citizenship. He loved the Chicago campus and its Institute of Oriental Studies (even exploring a little the Chinese language…oh, his enchantment with languages!). He loved the city and enjoyed walking its streets, going downtown on the elevated, or L, transit system. He never owned a car—”What for?” he would say. “Too much trouble.” Once, we circled together the full loop just for fun…big silly boys.
Máximo published several papers, not many but solid in content (just 15, perhaps one or two more, at a rate of about one per year), and three books dealing with eye movement (nystagmus and equilibrium) –; the effects of magnetic fields –, introducing a novel and beautiful explanation of visual perceptions triggered by strong magnetic fields, the indicator-dilution method , ; and information content of chemical structures . The latter subject was stemmed from the project I was involved with in those days at Baylor College with Leslie A. Geddes, and the second one originated in studies my father and I conducted together from 1958 to 1960. In the first two areas, Máximo can be considered a pioneer, having introduced good theory and realistic interpretation. Those involved in the space activity of those years were attracted by the subjects and even sponsored some of the studies. Remember the disturbances experienced by the early astronauts because of the sudden and strong accelerations during take-off and landing.
The retirement of Prof. Rashevsky (in 1967) soon meant the dissolution of the Committee on Mathematical Biology, and its members spread out to different places. Máximo was fortunate enough to get a joint position in the Department of Physiology of the Chicago College of Osteopathic Medicine, then in the Hyde Park area, to work with Dr. Albert F. Kelso, and at the Billings Hospital, to collaborate with Dr. César Fernández, a Chilean physician who had long before settled in the United States. Both places had beautiful labs, good equipment, and excellent technical assistance, so Máximo could reassume the experimental activities that had always attracted him so much. The Billings Hospital had an outstanding and modern three-dimensional centrifuge to run acceleration measurements in animals. Dr. Fernández and my father used to perform a delicate surgery on cats to isolate the semicircular canals, one by one, to separate out their contributions to the nystagmic eye movements. Moving are the words my father told his students of the college when he gave his farewell talk, on 3 May 1972:
This is my last lecture in this College. Next month I will retire because I will be 65. This does not mean at all that I will be an inactive individual. I will continue active intellectually as long as my skeleton responds. It has been a pleasure to be with all of you. The exchange with the class has been rewarding. All this I will keep in my memory. I wish good luck, success and happiness to all of you. Study, work and enjoy life. Preserve ideals and dreams above everything. Try to do your best every day for every patient. Suffering people need you. Your education will help them. As members of a society, think and behave in terms of mankind. Strive for peace, toleration and mutual understanding. Your fellowmen possess as much truth as yourselves. Give your soul and a soul will be given to you. Some day on the Earth the Republic of Mankind will be established. Thank you and goodbye.
A few days later, the same students offered my father a gold pocket watch with the following inscription: “You gave us your soul and we give you our hearts.”
Retirement, the Sociedad Científica Argentina, and the Institute of Cybernetics (1972–1985)
On their return to Argentina, Máximo and my mother went back to the old family house in the Almagro Quartier, a typical porteño central city area. Máximo’s activities were centered at the Sociedad Científica Argentina, created in July 1872, and he was elected as one of its two vice presidents in 1976, when Eduardo Pous Peña became president, until his demise in 1985 (Figure 8). Within the society, Máximo, with a handful of motivated people (César de la Vega, a physician, Emilio L. Díaz, a naval officer and physicist, Josué A. Núñez, a biologist specialized in bees and wasps, José M. Rosa Bunge, an advanced student of engineering, Sigfrido Lichtenthal, a computer engineer, and Osvaldo Skliar, a mathematician), organized the Institute of Cybernetics, calling for the collaboration of many individuals and holding frequent scientific meetings and courses. In addition, a small journal was published for several years (Figure 9). Máximo was a significant middleman to handle the official transactions needed for the final ownership of the society’s site (a superb downtown area, located at 1145 Santa Fe Avenue). Máximo was buried in the society’s pantheon at the traditional La Recoleta Cemetery, in Buenos Aires (Figure 10).
Another activity he put much effort into was the diffusion of Esperanto, the language that he spoke and wrote fluently, becoming the president of the Argentine League of Esperanto, endorsing by word and action its principles of human understanding and boundless countries beyond racial, cultural, or ideological differences. He also had the opportunity to spend a period in Pisa, Italy, working with Ottavio Pompeiano and producing a paper . About ten other papers were also published during this period but all in local journals of limited distribution and, unfortunately, hardly recognized by anyone. Máximo experienced deeply the bitter feeling of not walking the mainsteam science road, as often referred to; however, he never gave it much attention, as he carried out research for the honest and clear-cut reason of trying to uncover something, somehow making it known, and enjoying so doing.
His Intellectual Production
Máximo’s scientific production during the 1930s and 1940s (easily more than 30 papers, several within the clinical field) appeared in obscure unknown local journals that essentially buried in oblivion their results and ideas. Hence, no one ever noticed them. They were produced practically single-handedly and were poorly funded, with limited assistance from other collaborators, meaning that the experimental design, actual experimentation (often the construction of equipment, manual calculations, theoretical development), and final writing fell on his shoulders, and I would say he did all of this happily and with no regrets or complaints. I can testify because, during many years of my childhood and adolescence, he regularly took me to his Biophysics Lab at the Academy of Medicine to show me what science was about, explain to me what an action potential was, let me see by dissection a frog’s heartbeat, or to have me help him in simple tasks; clear and dear images are kept in my memory.
In my hands, there are several papers (about 12) dealing with the galvanic skin and electrodermal responses, covering aspects such as a physicomathematical interpretation, their anatomical distribution, and the physiological factors influencing them. In addition, he delved into the effects of electric fields on biological tissues, for example, in some plants, reporting growth inhibition, and even one publication in the field of electroencephalography. I also recall the equipment he used. Although there is no point in listing these contributions, one particular subject should be underlined: uterine contraction, which he did a significant amount of work on, with several papers and a final doctoral dissertation that can be considered highly significant. The Medical School of the University of Buenos Aires holds an original copy, and I keep one in my personal library (Figures 11 and 12) . This project was started in 1935 with several preliminary papers , . In one of them, applying the histerotonograph of E. Frey , Máximo recorded and interpreted uterine movements at different stages of labor (Figure 13). The origin of this instrument can easily be traced back to Ludwig’s kymograph .
Curiosity was one stimulus to which Máximo responded quickly, and a good example can be traced back to the reason he started to analyze phosphenes. It had been reported by the workers of an electrical energy company that, when performing repairs or maintenance close to very-high-voltage lines or transformers, they would see colored changing images followed by dizziness that forced them to stop their task for a while. Somehow, this fact reached him, and he rightly suspected that there would be a variable electromagnetic field action, which, in the end, would be fully innocuous. He searched the available bibliography, finding a few antecedents that gave him a lead, and, by applying basic physical laws, he produced an acceptable explanation (Figure 14).
Culture at large, not only in science, but arts, music (he played violin), philosophy and religions, theosophy and homeopathy (which he specialized in for a short time; after studying it for one year, he practiced with a colleague but soon withdrew from it, becoming deeply troubled by its many drawbacks and lack of scientific background, often plagued with sad results) were fields in which more or less deeply he delved in, always constructively and with interest, stimulating others around him. During the late 1940s or early 1950s he created with a very small group of young collaborators (Antonio Frumento, Ricardo H. Pichel, and others) the Sociedad Argentina de Biofísica. It did not last long, however, barely a couple of years, and, unfortunately, the attempt has been forgotten as the original document was lost.
Discussion and Conclusions
The importance of good teachers in elementary and high school is clearly demonstrated in Máximo’s success as well as the outstanding relevance of free public schools along with mandatory education up to the second level, if possible. Máximo appears as an example in which there was no previous family scientific influence. The material in my hands is more than enough for a full book, which is simply beyond my possibilities, at least for the time being. Máximo was characterized by a strong personality, sincerity and honesty, dedication to science and culture, and generosity and kindness, always away from the world noise and its ambitions. This note seems to rediscover my father, who amazingly still teaches me, at age 81, through his letters and manuscripts .
He was a humanist in capital letters, endorsed the concept of the republic of the world, and loved his native country, where he obtained regretfully little recognition, if any at all. He carried out theory, experimentation, and design and construction of equipment; he had excellent training in both the biological and physical sciences, and, most important of all, strong motivation and drive, and, on top of that, a tremendous scientific sense of ethics. Without a doubt, Máximo Valentinuzzi was a true scientist, humble and distant from honors, power, and glories. What else is needed? Doesn’t all this qualify him as a very early, if not the first, Latin American biomathematician, biophysicist, and bioengineer? Yes, as an old-timer acting like a child trying to mimic a Texan drawl, I can proudly say, “that was ma’ Dad!”
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- R. Forssmann-Falck, “Werner Forssmann: A pioneer of cardiology,” Am. J. Cardiol., vol. 79, pp. 651–660, Mar. 1997.
- M. E. Valentinuzzi and R. S. Leder, “Cardiac output: Since when, who and how,” IEEE Pulse, vol. 4, no. 6, pp. 2–10, 2013.
- D. Sobel, Galileo’s Daughter. New York: Penguin Books, 1999.
- M. E. Valentinuzzi, “A new beginning for human health,” IEEE Eng. Med. Biol. Mag., vol. 23, no. 4, pp. 67–72, July–Aug. 2004.
- M. E. Valentinuzzi, “50 years a biomedical engineer: Remembering a long and fascinating journey,” BioMed Eng. OnLine, vol. 11, no. 1, 2012.
- M. E. Valentinuzzi, “Half a century in BME: Fascinating road … and how brief it was, (in Spanish), Reseñas, virtual publication of the Asociación Argentina para el Progreso de la Ciencia, AAPC, vol. 1, no. 2, pp. 89–105, 2013.
- M. E. Valentinuzzi and A. J. Kohen, “The mathematization of biology and medicine: Who, when, how,” IEEE Pulse, vol. 4, no. 1, pp. 50–56, 2013.
- M. Valentinuzzi, “A mathematical interpretation of motor reactions to fixed and moving stimulation of the eye,” A report for the Aeromedical Division, Air Force Office of Scientific Research, Air Research and Development Command, United States Air Force, Rep. AF 18(600)-1454, Aug. 25, 1958.
- M. Valentinuzzi, “A mathematical interpretation of motor reactions to fixed and moving stimulation of the eye,” Bull. Math. Biol., vol. 21, pp. 327–341, 1959.
- M. Valentinuzzi, “An analysis of the mechanical forces in each semicircular canal of the cat under single and combined rotations,” Bull. Math. Biophys., vol. 29, pp. 267–289, 1967.
- C. Fernández and M. Valentinuzzi, “Nystagmic coriolis reaction in the cat,” Acta Oto-Laryngol., vol. 65, pp. 186–199, 1968.
- C. Fernández and M. Valentinuzzi, “A study on the biophysical characteristics of the cat labyrinth,” Acta Oto-Laryngol., vol. 65, pp. 293–310, 1968.
- M. Valentinuzzi, “Phase lag in periodic coriolis star nystagmus,” Med. Biol. Eng., vol. 8, pp. 559–574, 1970.
- J. Santos, M. Pascual, and M. Valentinuzzi, “On the electronic simulation of acceleratory nystagmus,” Lett. Appl. Eng. Sci., vol. 1, no. 4, pp. 355–362, 1973.
- M. Valentinuzzi, The Organs of Equilibrium and Orientation as a Control System (Biomedical Engineering and Computation Series). London and New York: Harwood Academic, 1980.
- M. Valentinuzzi, “Theory of magnetophosphenes,” Am. J. Med. Electron., vol. 1, no. 3, pp. 112–121, 1962.
- M. Valentinuzzi, “Notes on magnetic actions upon the nervous system,” Bull. Math. Biophys., vol. 27, pp. 203–214, 1965.
- M. Valentinuzzi, “A survey of theoretical approaches to magnetic growth inhibition,” Am. J. Med. Electron., vol. 1, no. 1, pp. 35–39, 1966.
- M. Valentinuzzi and R. W. Ferraresi, “Culture of macrophages under homogeneous static magnetic field,” Experientia, vol. 22, no. 312, pp. 1–2, 1966.
- M. Valentinuzzi, Magnetobiology and Complements of Magnetochemistry. Downey, CA: North American Aviation, Space and Information Systems Division, SID61-283, 1961.
- M. Valentinuzzi, Theory of Magnetophosphenes. Downey, CA: Aero-Space Laboratories, North American Aviation, Space and Information Systems Division, 1961.
- M. Valentinuzzi, A. A. Towsend, and A. F. Kelso, “A study of the liver circulation by indicator-dilution method with a conductivity cell,” J. Am. Osteopathic Assoc., vol. 70, pp. 124–127, 1971.
- M. Valentinuzzi, M. E. Valentinuzzi, and J. A. Posey, “Dilution curve area: Fast estimation by a compartmental procedure,” J. Assoc. Advancement Medical Instrum., vol. 6, no. 5, pp. 335–343, 1972.
- M. Valentinuzzi and M. E. Valentinuzzi, “Information content of chemical structures and some possible biological applications,” Bull. Math. Biophys., vol. 24, pp. 11–27, 1962.
- O. Pompeiano and M. Valentinuzzi, “A mathematical model for the mechanism of rapid eye movements induced by an anticholinesterase in the decerebrate cat,” Arch. italienne de Biologie, vol. 114, pp. 103–154, 1976.
- M. Valentinuzzi, “Contribution to the Physical Study of Uterine Contraction,” (in Spanish), Doctoral Dissertation, Medical School of the UBA, Buenos Aires, 1950.
- M. Valentinuzzi, “On a mathematical expression of the myogram,” (in Spanish), Revista Médica Latino-Americana, vol. XXIII, no. 270, pp. 3–25, Mar. 1938.
- M. Valentinuzzi, “On some physics notions of the gravid uterus: Pressure, tension, contraction and work,” (in Spanish), Boletín de la Sociedad de Obstetricia y Ginecología de Buenos Aires, vol. XVIII, no. 3, pp. 83–125, June 1939.
- E. Frey, “The hysterotonograph: A new apparatus with automatic writing system for the clinical labor checking,” (in German), Zentralblatt für Gynaekologie, vol. 57, p. 545, 1933.
- M. E. Valentinuzzi, K. Beneke, and G. E. González, “Ludwig: The bioengineer,” IEEE Pulse, vol. 3, no. 4, pp. 68–78, 2012.
- M. Valentinuzzi, “The manuscript letters: Are they forever past?” IEEE Pulse, vol. 4, no. 3, pp. 48–51, 2013.