Medical physics workforce: A global perspective

PurposeThe International Organization for Medical Physics (IOMP) performed a detailed study following the first survey published in 2015 with the particular objectives: 1) gather data on global medical physicists (MPs) workforce, 2) identify differences between geographical regions and, 3) investigate whether there is a gender dimension in higher hierarchy positions.MethodsAn online questionnaire was send to IOMP members and contact points in countries where no professional MPs society existed. Information requested: total number (N) of MPs (men and women), N of current elected executive board (EB) of societies and women proportion in the board, president gender and number of women presidents for the last 10 years. IOMP archives were also investigated for data on gender composition related to chairs of committees, officers and IOMP awardees.ResultsNinety three countries reported 29,179 MPs, from which 8702 were women (29.8%) and 20,477 men. The most dense MPs population was in Europe (34%), followed by North America (33%) and Asia/Oceania (24%). Societies EB women members constitute 21–40%, but rarely reach the presidential position. The IOMP archived data show that women MP representation decreases in higher hierarchy positions.ConclusionsGlobal MPs production does not meet clinical needs especially in Latin America/Caribbean and Africa (6% of total MPs workforce and small number of MPs/million of population). Rough estimations showed that approximately 58,950 MPs will be required by 2035. Women representation is away from the United Nations and European Commissions goals. Women representation in higher hierarchy position is low.     

Non-breeding fæder Ruffs Philomachus pugnax associate according to sex,not morphology

Capsule Fæders (males that are female look-alikes) associate with males rather than females, at several different spatial scales.

Aims To test the prediction that the occurrence in space and time of fæders on ecological grounds should track that of females.

Methods The fraction of fæders was estimated in five morphometric data sets that were collected over four decades in four different countries in three different seasons (comprising 9133 Ruffs). The regression of fæder–female fractions was tested against the null model assuming that the number of fæders is 1.0% of females.

Results The fraction of fæders in catches averaged 1.03%, varying between 0.3% in autumn in the UK up to 0.85% in Sénégal in winter and 1.04% in The Netherlands in spring. On a stopover in The Netherlands the fraction decreased from 1.3% to 0.7% when the females started to arrive. At all four spatial and temporal scales the regression of fæder–female fractions deviated from the null model: we found high fractions of fæders in catches with low fractions of females, indicating that fæders rather associate with the larger-sized ‘normal’ males.

Conclusion We suggest that fæders spend the winter, and migrate with, the larger-sized lekking males, and we propose that any survival costs associated with the use of suboptimal habitats is compensated by higher reproductive success as sneakers on leks.     

Emergence and mating behavior of the oriental fruit moth Cydia molesta (Lepidoptera: Tortricidae) and its potential for reproduction

The Oriental fruit moth, Cydia molesta (Busck, 1916) (Lepidoptera: Tortricidae), is a key pest of fruit and is widely distributed around the world. There are important connections between its behavior and biology and its management in agriculture, but few studies have investigated the associations between adult behaviors and oviposition. In this study, adult emergence, mating, and reproduction were investigated under laboratory and field conditions. The ratio of females to males at eclosion was approximately 1:1. When one virgin female had access to one virgin male, 66% and 34% of the couples copulated just once and twice, respectively; and the infertility rate of eggs (21.39 ± 1.25%) did not vary daily. Males, given access to one new female daily, could copulate multiple times, whereas females seldom mated more than once, indicating a male-biased operational sex ratio, but mating status of the male parent had no effect on progeny egg reproduction. Also, the number of eggs that hatched by all female partners of a male was inversely proportional to copulation duration for the female laying the eggs for total female reproductive success; and the number of eggs laid by all female partners of a male was proportional to their number of matings for total male reproductive success. However, the total number of eggs that hatched did not significantly differ for eggs laid by a female given new virgin males daily for mating (17.75 ± 4.28) versus eggs laid by virgin females (19.17 ± 7.51) presented daily with a male that re-mated daily with the series of females. Therefore, our results showed that females engaged in mate choice and males engaged in mate competition, affecting egg production, a factor that may be used to enhance mating disruption technology against Cydia molesta.     

22nd International Conference on Medical Physics 2016, Bangkok,Thailand; Medical physics propelling global health

As medical technology evolves and patient needs increase, the need for well-trained and highly professional medical physicists (MPs) becomes even more urgent. The roles and responsibilities of MPs in various departments within the hospital are diverse and demanding. It is obvious that training, continuing education and professional development of MPs have become essential.One of the ways for an MP to advance his or her knowledge is to participate in conferences and congresses. Last year, the 22nd International Conference of Medical Physics (ICMP 2016) took place in Bangkok, Thailand. The event attracted 584 delegates with most of the participants coming from Asia. It attracted also delegates from 42 countries. The largest delegations were from Thailand, Japan and South Korea. ICMP 2016 included 367 oral presentations and e-posters, most of these being in the fields of Radiation Therapy, Medical Imaging and Radiation Safety. All abstracts were published as an e-book of Abstracts in a supplement to the official IOMP Journal. Many companies had exhibition stands at ICMP2016, thus allowing the participants to see the latest developments in the medical physics-related industry. The conference included 42 mini-symposia, part of the first “IOMP School” activity, covering various topics of importance for the profession and this special issue follows from the success of the conference.     

Changes in biological anthropology: results of the 1998 American Association of Physical Anthropology Membership Survey

In response to the results of the 1996 survey of the membership of the American Association of Physical Anthropology (AAPA), the Executive Committee of the Association sponsored a follow-up survey designed to assess gender and specialty differences in training, employment, academic status, mentoring, and research support. A total of 993 questionnaires was analyzed, representing approximately 62% of the 1998 membership of the Association. There has been a marked shift in the number of males and females in the discipline from the 1960s to the 1990s. While 51.2% of all respondents are female and 48.8% are male, 70% of the students are female. Chi-square tests indicate significant differences between males and females by highest degree, age, status, obtaining a tenure-track position, receiving tenure, and taking nontenure-track employment before receiving a tenure-track position. In recent years, there has been an increasing number of females in the ranks of assistant and associate professors; however, this is not true for the rank of professor. There are also significant differences between males and females by specialty within the discipline: researchers in primatology, human biological variation, skeletal biology, and paleopathology are primarily female, while researchers in human and primate evolution are increasingly female.     

Medical physics graduate education in Mexico and its relation to the advances in radiation oncology

AimTo evaluate the state of graduate education in medical physics and progress in radiation oncology (RO) equipment in Mexico since 2000, when conferring degrees from two master’s-degree programs in Medical Physics began.BackgroundMedical physics is a Health Profession and there are international recommendations for education, training, and certification. Both programs follow these education guidelines. The most common clinical occupation of graduates is in RO services. Techniques in Mexican RO include traditional and high-precision procedures.MethodsAcademic and occupational information about the programs and their graduates were obtained from official websites. Graduates were invited to respond to a survey that requested information about their present job. We obtained data on RO equipment and human resources from public databases and estimated staffing requirements of medical physicists (MPs).ResultsMedical physics programs have graduated a total of 225 MPs. Half of them work in a clinical environment and, of these, about 90 work in RO services. MPs with M.Sc. degrees constitute 36% of the current MP workforce in RO, estimated to be 250 individuals. Survey responses pointed out the main merits and limitations of the programs. The number of MPs in RO has increased fivefold and the number of linacs sixfold in 15 years. The present number of MPs is insufficient, according to published guidelines.ConclusionAll MPs in RO services with advanced modalities must be trained following international recommendations for graduate education and post-graduation clinical training. Education and health institutions must find incentives to create more graduate programs and clinical residencies.     

Gender difference in blood cadmium concentration in the general population: Can it be explained by iron deficiency?

IntroductionGender differences in blood cadmium concentrations and the effect of iron deficiency on blood cadmium levels were analyzed in a representative sample of Koreans assessed in the Korean National Health and Nutritional Examination Survey (KNHANES) 2008–2011.MethodsA rolling sampling design was used to perform a complex, stratified, multistage probability cluster survey of a representative sample of the non-institutionalized civilian population in South Korea. Serum ferritin was categorized as low (<15.0 μg/L), low normal (15.0–<30.0 μg/L for females and 15.0–<50.0 μg/L for males), and normal (≥30.0 μg/L for females and ≥50.0 μg/L for males), and its association with blood cadmium levels was assessed after adjustment for various demographic and lifestyle factors.ResultsThe geometric mean (GM) of the blood cadmium level was significantly higher in females than in males, and significantly higher in older individuals for both genders. After controlling for covariates, multiple regression analysis with interaction terms showed that blood cadmium was correlated with serum ferritin levels only in pre-menopausal females.DiscussionIron deficiency is associated with blood cadmium levels in a representative sample of pre-menopausal females, as evaluated in KNHANES. Gender differences in blood cadmium concentration may not be due solely to an iron deficiency-associated increase in blood cadmium.     

Proximate causes of sexual size dimorphism in Colorado pikeminnow, a long‐lived cyprinid

Evidence for sexual size dimorphism (SSD) and its possible causes were examined in the endangered Colorado pikeminnow Ptychocheilus lucius, a large, piscivorous, cyprinid endemic to the Colorado River system of North America. Individuals representing 18–24% of the upper Colorado River population were captured, measured, sexed and released in 1999 and 2000. Differing male and female total length‐(L_T) frequency distributions revealed SSD with females having greater mean and maximum sizes than males. Although both sexes exhibit indeterminate post‐maturity growth, growth trajectories differed. The point of trajectory divergence was not established, but slowed male growth might coincide with the onset of maturation. Differing growth rate was the dominant proximate cause of SSD, accounting for an estimated 61% of the observed difference in mean adult L_T. The degree of SSD in adults, however, was also related to two other factors. Evidence suggests males become sexually active at a smaller size and earlier age than females; a 2 year difference, suggested here, accounted for an estimated 12% of the between‐sex difference in mean adult L_T. Temporal shifts in gender‐specific survival accounted for an additional 27% of the observed between‐sex difference in mean adult L_T. Estimated age distributions indicated a higher number of older females than older males and more younger males than younger females in the population during the period of sampling. Dissimilarity of age distributions was an unexpected result because the male : female population sex ratio was 1 : 1 and estimates of long‐term annual survival for adult males and females were equal (88%). Future assessments of SSD in this population are apt to vary depending on the prior history of short‐term gender‐specific survival. Without recognizing SSD, non‐gender‐specific growth curves overestimate mean age of adult females and underestimate mean age of adult males of given L_T. Assuming age 8 years for first reproduction in males and age 10 years for females, the adult male : female ratio was estimated as 1·1 : 1 and mean adult age, or generation time, was estimated as 16·4 years for males and 18·4 years for females.     

Valkyries: Was gender equality high in the Scandinavian periphery since Viking times? Evidence from enamel hypoplasia and height ratios

Scandinavian countries currently have very high values of female autonomy. Was this already the case in Viking Times? In this study, we trace the roots of gender equality in the Scandinavian periphery over the past two millennia. We evaluate and recommend a new measure of early gender equality: relative enamel hypoplasia values of males and females. This new indicator allows us to trace relative health and nutritional equality, using archaeological evidence. We find that Scandinavian women in the rural periphery already had relatively good health and nutritional values during the Viking era and the medieval period thereafter. The corresponding value is 0.8 equality advantage for Scandinavian women, whereas in the rest of Europe most values fall in a band around 1.2 ratio units. This suggests that the currently high gender equality had a precedence during the Middle Ages.     

Reproductive biology of the viviparous scorpion,Liocheles australasiae (Fabricius) (Arachnida,Scorpiones, Scorpionidae). I. Absence of males in two natural populations

Summary

Sex of the viviparous scorpion, Liocheles australasiae, collected in two localities in Asia at various seasons during the years 1977 to 1983, was examined on the basis of morphology of gonads and germ cells. A total of 569 specimens consisted of 408 pregnant and 7 interpregnant adult females, 126 immature or nymphal females, and 28 young nymphs in which the sex was not distinguishable. Distinct males were never collected in either locality at any season. No spermatozoa were found in any region of the female reproductive systems. Judging from these results, males do not occur in these populations, and it is presumed that these populations reproduce by thelytokous parthenogenesis.     

Postoperative Estradiol Levels Associate With Development of Primary Graft Dysfunction in Lung Transplantation Patients

BackgroundPrimary graft dysfunction (PGD) frequently complicates lung transplantation in the immediate postoperative period. Both female gender and estradiol modulate the body's response to injury and can influence the rate of alveolar fluid clearance.ObjectiveWe hypothesized that female gender and higher estradiol levels would be associated with a lower risk of PGD after lung transplantation.MethodsWe measured plasma estradiol levels preoperatively, 6 hours postoperatively, and 24 hours postoperatively in a cohort of 111 lung transplant recipients at 2 institutions.ResultsMean age was 57 years (12.5) and 52% were female. Median postoperative estradiol level was 63.9 pg/mL (interquartile range, 28.8−154.3 pg/mL) in male and 65.1 pg/mL (interquartile range, 28.4−217.2 pg/mL) in female patients. Contrary to our hypothesis, higher estradiol levels at 24 hours were associated with an increased risk of PGD at 72 hours in male patients (P = 0.001). This association was preserved when accounting for other factors known to be associated with PGD. However, there was no relationship between gender and risk of PGD or between estradiol levels and PGD in females.ConclusionThese findings suggest that there might be different biologic effects of estrogens in males and females, and highlight the importance of considering gender differences in future studies of PGD.     

The Epidemiology of Alcohol Use and Alcohol Use Disorders among Young People in Northern Tanzania

IntroductionAlcohol use is a global public health problem, including as a risk factor for HIV infection, but few data are available on the epidemiology of alcohol use and alcohol use disorders (AUD) among young people in sub-Saharan Africa.MethodsWe conducted a cross-sectional survey among 4 groups of young people aged 15–24 years old (secondary school students, college/university students, employees of local industries and casual labourers) in two regions (Kilimanjaro and Mwanza) of northern Tanzania. Using a multistage stratified random sampling strategy, we collected information on demographics, alcohol use, and behavioural factors. We screened severity of alcohol use using the Alcohol Use Disorder Identification Test (AUDIT) and estimated the quantity and frequency of alcohol consumption using the timeline-follow-back-calendar (TLFB) method.ResultsA total of 1954 young people were surveyed. The prevalence of reported alcohol use was higher among males (47–70% ever users and 20–45% current users) than females (24–54% ever users and 12–47% current users). Prevalence of use was substantially higher in Kilimanjaro than Mwanza region. In both regions, participants reported high exposure to alcohol advertisements, and wide alcohol availability. College students reported the highest prevalence of current alcohol use (45% among males; 26% among females) and of heavy episodic drinking (71% among males; 27% among females) followed by casual labourers. Males were more likely to have AUD (an AUDIT score ≥8) than females, with 11–28% of males screening positive for AUD. Alcohol use was associated with male gender, being in a relationship, greater disposable income, non-Muslim religion and a higher number of sexual partners.ConclusionsAlcohol use is a significant problem among young people in northern Tanzania. There is an urgent need to develop, pilot and deliver interventions to help young people delay initiation and reduce levels of harmful drinking, particularly among college students and casual labourers.     

Reproductive strategies of the exotic Pharaoh's ant,Monomorium pharaonis (L.) (Hymenoptera: Formicidae) in Brazil

Summary

The production of sexual forms in laboratory colonies of Monomorium pharaonis was followed over a 19-month period. Cycles of production occurred at intervals of 4 months, with male investment inversely proportional to the number of gynes produced. There was a tendency for colonies to produce only males or females as total sexual production increased. Sperm counts of known-aged males suggest that they mate twice, in contrast to European populations. Sex-ratio was heavily female-biased, contrary to predictions for polygynous ant species.     

Head impact exposure in male and female collegiate ice hockey players

The purpose of this study was to quantify head impact exposure (frequency, location and magnitude of head impacts) for individual male and female collegiate ice hockey players and to investigate differences in exposure by sex, player position, session type, and team. Ninety-nine (41 male, 58 female) players were enrolled and 37,411 impacts were recorded over three seasons. Frequency of impacts varied significantly by sex (males: 287 per season, females: 170, p<0.001) and helmet impact location (p<0.001), but not by player position (p=0.088). Head impact frequency also varied by session type; both male and female players sustained more impacts in games than in practices (p<0.001), however the magnitude of impacts did not differ between session types. There was no difference in 95th percentile peak linear acceleration between sexes (males: 41.6 g, females: 40.8 g), but 95th percentile peak rotational acceleration and HITsp (a composite severity measure) were greater for males than females (4424, 3409 rad/s², and 25.6, 22.3, respectively). Impacts to the back of the helmet resulted in the greatest 95th percentile peak linear accelerations for males (45.2 g) and females (50.4 g), while impacts to the side and back of the head were associated with the greatest 95th percentile peak rotational accelerations (males: 4719, 4256 rad/sec², females: 3567, 3784 rad/sec² respectively). It has been proposed that reducing an individual's head impact exposure is a practical approach for reducing the risk of brain injuries. Strategies to decrease an individual athlete's exposure need to be sport and gender specific, with considerations for team and session type.     

How Short is Too Short According to Parents of Primary Care Patients

ObjectiveHeight is a physical trait on a continuum. The threshold between normal and abnormal is arbitrarily set but can potentially influence medical decision-making. We sought to examine parents’ perceptions of adult heights and associated demographic factors.MethodsParents of pediatric primary care patients of various heights completed a one-time survey. Parents answered the question “How short is too short?” for adult males and females. The results were summarized as median [interquartile range]. Factors significantly associated with height threshold by simple linear regression were included in a multivariable mixed effects analysis of covariance model.ResultsA total of 1,820 surveys were completed (83% response rate, 1,587 females, 231 males). The median threshold height deemed too short for adult females was 56 inches [48, 59] among male respondents and 57 inches [50, 60] among females (P < .05). The median threshold height for adult males was 61 inches among males [60, 64] and females [59, 66] (P < .05). The median of male minus female heights per respondent (delta heights) was 5 [2, 7] inches. Factors found to be significant main effects in a parsimonious model were sex of the adult considered, height of respondent, sex of respondent, respondent race, primary care practice, income, and having concerns about their child’s height.ConclusionTaller acceptable height thresholds were perceived by respondents who were taller, wealthier, white, female, from nonurban practices, or who had a personal concern about their child’s height. Male heights were expected to be taller than female heights. Such traits may influence who is concerned and more likely to seek medical treatment for their children. (Endocr Pract. 2014;20: 1113-1121)     

Global distribution and invasion pattern of oriental fruit fly,Bactrocera dorsalis (Diptera: Tephritidae)

Since the start of the 20th century, many invasive alien species (IAS) have spread rapidly around the world, causing serious threats to economies, societies and the environment. Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) is an important quarantine insect species in many countries that spread around the world over the last century. This review collected information on the distribution of B. dorsalis to explore the patterns of its invasion expansion. We found B. dorsalis to be distributed in 75 countries (comprised of 124 geographical distribution regions: provinces or states) in Asia, Africa, North America, South America and Oceania up to 2017. Asia and Africa were the most represented regions, accounting for 86.3% of the total number of countries. From 1910 to 1990, B. dorsalis was only found in five countries, but in the last three decades, it has experienced a sharp increase in its rate of spread, invading 70 more countries. Global temperature anomaly has significantly positive correlation with the spread of B. dorsalis. The results of this review provide a theoretical basis for understanding and predicting the continued spread of B. dorsalis under global changes.     

Participation of women medical Physicists in European scientific events: The European experience

PurposeThough the number of women scientists is increasing over the years, studies show that they are still under-represented in leadership roles. The purpose of this work is to establish the percentage of women Medical Physicists (wMPs) that have participated in European scientific events and evaluate it as an indication of the current position of women in the field of Medical Physics in Europe and to propose possible ways to encourage their participation.Materials and MethodsData regarding the participants in European scientific events of Medical Physics were collected. The participants were divided into categories according to the program of the events and their gender was identified. The percentage of wMPs in each category was evaluated.ResultsThe participation of wMPs attending courses is greater than 50%. The categories with the greatest participation are “Organizing Committees”, “Chairpersons-Moderators” and “Oral Presentations”. The categories with the lower participation of wMPs are “Scientific Committee”, “Symposiums” and “Invited Speakers”. None of wMPs were represented as “Course Directors”.ConclusionsThe attendance of wMPs in courses is slightly greater than average. However, wMPs do not have an equally important recognition in special invited roles in conferences. They are still under-represented in “Scientific Committees”, “Invited Speakers”, “Symposiums” and “Course directors”. wMPs should be encouraged to participate even more actively in European conferences and the organizing committees should invite more wMPs in special roles. More studies concerning the status of female MPs in each country separately should be encouraged as they will help in understanding the position of wMPS in Europe.