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Abstract This paper reports the design of a biosensor for sensitive, low-cost measurement of lead in drinking water. The biosensor uses a genetically-modified strain of Escherichia coli, which serves as both signal amplifier and reporter of lead in water, measured via colour change. We developed the PlomBOX measurement platform to image this colour change and we demonstrate its capability to detect concentrations as low as the World Health Organisation upper limit for drinking water of 10 ppb. Our approach does not require expensive infrastructure or expert operators, and its automated sensing, detection and result visualisation platform is user-friendly and robust compared to existing lead biosensors—critical features to enable measurement by non-experts at the point of use.

Coarse mineral dust particles have been observed much further from the Sahara than expected based on theory. They have impacts different to finer particles on Earth's radiative budget, as well as carbon and hydrological cycles, though they tend to be under-represented in climate models. We use measurements of the full dust size distribution from aircraft campaigns over the Sahara, Canaries, Cabo Verde and Caribbean. We assess the observed and modelled dust size distribution over long-range transport at high vertical resolution using the Met Office Unified Model, which represents dust up to 63.2 µm diameter, greater than most climate models. We show that the model generally replicates the vertical distribution of the total dust mass but transports larger dust particles too low in the atmosphere. Importantly, coarse particles in the model are deposited too quickly, resulting in an underestimation of dust mass that is exacerbated with westwards transport; the 20–63 µm dust mass contribution between 2 and 3.7 km altitude is underestimated by factors of up to 11 in the Sahara, 140 in the Canaries and 240 in Cabo Verde. In the Caribbean, there is negligible modelled contribution of d > 20 µm particles to total mass, compared to 10 % in the observations. This work adds to the growing body of research that demonstrates the need for a process-based evaluation of climate model dust simulations to identify where improvements could be implemented.

Abstract The current experiments searching for neutrinoless double- $$\beta $$ β ( $$0\nu \beta \beta $$ 0 ν β β ) decay also collect large statistics of Standard Model allowed two-neutrino double- $$\beta $$ β ( $$2\nu \beta \beta $$ 2 ν β β ) decay events. These can be used to search for Beyond Standard Model (BSM) physics via $$2\nu \beta \beta $$ 2 ν β β decay spectral distortions. 100Mo has a natural advantage due to its relatively short half-life, allowing higher $$2\nu \beta \beta $$ 2 ν β β decay statistics at equal exposures compared to the other isotopes. We demonstrate the potential of the dual read-out bolometric technique exploiting a 100Mo exposure of 1.47 kg $$\times $$ × years, acquired in the CUPID-Mo experiment at the Modane underground laboratory (France). We set limits on $$0\nu \beta \beta $$ 0 ν β β decays with the emission of one or more Majorons, on $$2\nu \beta \beta $$ 2 ν β β decay with Lorentz violation, and $$2\nu \beta \beta $$ 2 ν β β decay with a sterile neutrino emission. In this analysis, we investigate the systematic uncertainty induced by modeling the $$2\nu \beta \beta $$ 2 ν β β decay spectral shape parameterized through an improved model, an effect never considered before. This work motivates searches for BSM processes in the upcoming CUPID experiment, which will collect the largest amount of $$2\nu \beta \beta $$ 2 ν β β decay events among the next-generation experiments.

Future fusion reactors like ITER and DEMO will have all-tungsten (W) walls and long pulses. These features will make wall conditioning more difficult than in most of the existing devices. The W Environment Steady-state Tokamak (WEST) is one of the few long pulse (364 s) fusion devices with actively cooled W plasma-facing components in the world. WEST is a unique test bed to study impurity migration and plasma density control via reactor relevant wall conditioning techniques. The phase II of WEST operations began in 2022, after the installation of a new lower divertor, now entirely equipped with actively cooled, ITER grade, W monoblocks. After pump down, we baked WEST between 90 °C and 170 °C for ∼2 weeks. After 82.5 h at 90 °C and 33 h at 170 °C, vacuum conditions were stable with a vessel pressure of 6x10-5 Pa and mass spectra dominated by H2 molecules. While at 170 °C, we performed ∼40 h of D2 glow discharge cleaning (GDC) and ∼5 h of glow discharge boronization (GDB), using a 15 %-85 % B2D6-He mix and a total boron mass of ∼12 g. This was the very first GDB at such high temperature for WEST. The whole wall conditioning sequence led to a ∼10 times reduction of the H2O signal as well as to a ∼3 times reduction of the O2 signal, according to mass spectra. Once back to 70 °C, the vessel pressure was 5.5x10-6 Pa and plasma restart was seamless with ∼30 s cumulated over the very first 5 pulses and an Ohmic radiated power fraction Frad = 0.6, showing successful conditioning of the new ITER grade divertor. The effect of the first, ‘hot’ GDB faded with a characteristic cumulative injected energy of 2.45 GJ and saturation towards Frad ∼0.8. After 1.4 h and 7.5 GJ of cumulative plasma time and injected energy, we carried out a second GDB, this time at 70 °C. This ‘cold’ GDB initially led to a much lower Ohmic Frad = 0.3–0.4 but the effect lasted ∼7 times less, with a characteristic cumulative injected energy of 0.37 GJ. At the end of the campaign, we cumulated ∼3h and ∼30 GJ through repetitive, minute long pulses without any boronization. Throughout this 4-weeks-long experiment, Frad in the 4 MW heating phase evolved only marginally (from 0.5 to 0.55). This increase is mostly due to the build-up of re/co-deposited layers on both lower divertor targets.

This paper summarizes the observations on the Unidentified Flying Object (UFO) observed during the first high fluence campaign performed in WEST. The campaign was characterized by high erosion and deposition rates, generating dusts and deposits prone to flaking during plasma operation. A total of 686 UFOs have been detected for 384 discharges executed, in which 133 UFOs lead to a disruption. These UFOs appear mostly during the low hybrid heating ramp-up early in the discharges. The mechanisms leading to a disruption is described as well as the delay available to react after the UFO entering in the plasma. The UFOs originate mostly from the high field side corresponding to the thick deposit area. These UFOs can be debris from a preceding disruption (≈27 %) or come from progressive loss of adherence of the thick deposits (≈55 %) under plasma cycling or more likely by disruption on this area. Finally, the thermal resistance of the poorly attached deposits has been calculated in the range from 2.10−4 °C m2/W to 1.10−3 °C m2/W coherent with previous observations in the high field side of the JET divertor.

During the 2017–2019 WEST operation, a set of ITER-like plasma-facing units consisting of tungsten monoblocks was installed on the lower divertor. Despite modest heating power, 27 % of these monoblocks had cracks on their poloidal leading edges, which were not protected by a toroidal bevel. A comprehensive experimental characterization of the 133 cracked monoblocks indicates that damage occurs near the plasma strike point areas where neat cracks separated by 0.15–0.5 mm in the poloidal direction were observed. Cracks are up to 1 mm long and 1 mm deep and did not affect the lower divertor ability to sustain long pulses. The most important parameter affecting crack formation is the relative vertical misalignment between components.

We analysed deposits collected on the lower divertor of WEST after the first high fluence campaign performed in 2023. Deposits were collected on the high field side (thick deposition area) of 2 ITER-grade plasma facing units (PFUs), located on different toroidal positions. Using focused ion beam cross sectioning, the deposits were found to be very thick (12–55 µm). A significant difference was observed in the toroidal direction with thicker deposits for the PFU located at the maximal heat load in the inner side, showing a deposition pattern due to the toroidal magnetic field modulation. Deposits present a complex layer-by-layer structure with dense layers, some melted parts and porosities within the layers. The deposition is mainly composed of tungsten with oxygen, boron, carbon and traces of nitrogen whose composition vary along the radial direction. We identified W-rich deposits in the high plasma flux area near the inner strike point and deposits rich in O, B, C and N in the low plasma flux area further away from this strike point. W dense layers of about 5 up to 40 µm thick in the thick deposit area near the strike point were attributed to the high fluence campaign. Pure boron layers resulting from wall conditioning and processed by plasma wall interactions were also observed.

An initial high fluence campaign was performed in WEST, in 2023, on the newly installed actively cooled tungsten divertor composed of ITER-grade monoblocks. The campaign consisted in the repetition of a 60 s long Deuterium L-mode pulse in attached divertor conditions, cumulating over 10000s of plasma exposure. A maximum deuterium fluence of approximately 5⋅1026 m−2 was reached in the outer strike point region, representative of a few high performance ITER pulses. Gross tungsten erosion inferred from visible spectroscopy shows that the most eroded plasma facing component is the inner divertor target with rates ten times larger than on the outer divertor target. The outer midplane tungsten bumpers, located a few centimeters from the plasma, show gross erosion rates two times lower than at the outer divertor. We conclude that the outer midplane bumpers have a negligible contribution to the long range tungsten migration and deposition onto the lower divertor. The cumulated gross erosion rate on the inner divertor translates in an effective gross erosion thickness of about 20μm, while it is about 2μm for the outer divertor. Strikingly, these orderings coincide with the thickness of deposits found locally on the divertor: the exposed surfaces of high field side monoblocks are covered with several tens of μm tungsten deposits, while on the lower field side, few μm thin tungsten deposits are only found on the magnetically shadowed parts of monoblocks. The strong impact of those deposits on WEST operation, namely perturbation of surface temperature measurement with infra-red thermography, and the emission of flakes causing radiative perturbation of the confined plasma, calls for anticipating similar issues in ITER. In particular, the start of research operation shall consider the definition of a divertor erosion budget in order to anticipate the formation of deleterious deposits.

The estimation of the heat flux density distribution profiles in tokamak devices is a very important research topic for edge plasma physics purposes and also to ensure the safety of the machine. In the radial direction, the heat flux exhibits an exponential decay that could be captured by thermal sensors distributed in the plasma facing components. Radially distributed thermal sensors based on Fiber Bragg grating technology have been embedded in the WEST lower divertor to study the heat flux deposition profiles during plasma operation. The comparison between embedded measurements and a 3D finite element model shows a small decay length (5 – 10 mm) on top of a wider heat flux with a decay length around 30 to 50 mm. A tool using neural network has been developed in order to predict the values of the different parameters describing the deposited heat flux from embedded temperature measurements in steady state. A large span of deposited heat fluxes with maximum heat flux ranging from 1 to 9 MW/m2 and decay length from 5 to 50 mm were characterized using this tool over a database of more than 250 experimental L-mode pulses performed in WEST in attached divertor configuration. The comparison of the predicted heat flux parameters values with macroscopic plasma parameters have revealed the appearance of the narrow component with the increase of the divertor power load (Pdiv) with a threshold dependant of the plasma current (IP).

After 3 h of accumulated time from repeated plasma shots during C7 campaign performed in 2023, a deposited layer appeared on the ITER-grade W-monoblock of the lower divertor of WEST, mostly on the high field side. The growth of the deposit was observed during the campaign using infrared cameras, showing a large increase of the area covered by the deposit (x4) in the last two hours of cumulated plasma time. The deposit becomes problematic for the operation as it generates flakes which provoke radiative collapse when entering the plasma. A cleaning of the lower divertor is mandatory. A first cleaning was done using adhesive tape to remove all weakly adhered parts of the deposit. This method was chosen because it was easy to implement and did not generate dusts inside the tokamak. The cleaning enables partial removal of the more lightly adhered deposits but a large fraction remains stuck on the monoblock. A second cleaning was tried during 2024 operation by using the plasma as cleaner. A scenario was developed to put the inner strike line directly on the deposit to heat it and try to remove it by thermal stress. The deposit reaches temperature up to 1560°C but was not removed. The impurities generated were higher than normal operation and decreased during the cleaning session (−50% of light impurities observed at the end of the cleaning discharge session), showing an effect of cleaning by removing impurities from the deposit.

Reactor relevant fusion devices will use tungsten (W) for their plasma facing components (PFCs) due to its thermomechanical properties and low tritium retention. However, W introduces high-Z impurities into the plasma, degrading its performance. Different wall conditioning methods have been developed to address this issue, including coating of W PFCs with layers of low-Z material. Wall conditioning by boron (B) powder injection using an impurity powder dropper (IPD) is being studied in WEST. Two series of experiments were conducted since the installation of the new ITER grade full W divertor. During the first series in 2023 ∼ 1 g of B powder was injected in total at a maximum rate of ∼ 58 mg/s, both of which are three times greater than respective values in the initial WEST powder injection experiments. The second series of experiments included injection of B and BN powders for comparison of their effects on plasma performance. The presence of an instantaneous conditioning effect is suggested by visible spectroscopy measurements of low-Z impurity lines and a rollover of total radiated power past an injection rate of ∼ 20 mg/s was observed. Presence of B coating layer formation is supported by the evolution of the average radiance of visible lines of B, W and oxygen (O). To understand B transport, an interpretative modeling workflow is employed, utilizing the SOLEDGE-EIRENE fluid boundary plasma code and the Dust Injection Simulator (DIS) code. Parameters like B perpendicular diffusivity and recycling coefficients are varied to match experimental results to see if the initial assumption of B sticking to the PFCs immediately after the contact with the wall is adequate for correctly modelling its distribution on the PFCs.

X-Point Radiator (XPR) regimes have been obtained in WEST tokamak experiments with nitrogen seeding during the experimental campaigns of 2023 and 2024. These experiments showed the formation of a stable toroidal radiating ring near the X-point, similar to observations in other devices such as JET, ASDEX-Upgrade, TCV, and COMPASS. In WEST, the onset of this regime is associated with a sharp transition of the divertor plasma from hot to cold and dense conditions, with increased particle fluxes, indicating that the plasma is not detached. At the same time, core conditions are significantly improved. These scenarios were successfully controlled in WEST using an interferometry line-of-sight passing through the X-point. Interpretative modeling of these discharges with the SOLEDGE3X-EIRENE code reveals that a physics mechanism needed to stabilize WEST nitrogen XPRs is not present when driving the simulations at constant power. On the contrary, a stable XPR can be obtained by increasing the power injected at the time of the XPR onset to represent the reduction of W contamination, highlighting the need to describe the plasma dynamics and go toward integrated core–edge simulations.

Atmospheric aerosol particles have a profound impact on Earth's climate by scattering and absorbing solar and terrestrial radiation and by impacting the properties of clouds. Research aircraft such as the Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR) Falcon are widely used to study aerosol particles in the troposphere and lower stratosphere. However, transporting a representative sample to the instrumentation inside the aircraft remains a challenge due to high airspeeds and changing ambient conditions. In particular, for high-quality coarse-mode aerosol measurements, knowledge about losses or enhancements in the aerosol sampling system is crucial. In this study, the sampling efficiency of the aerosol inlet aboard the Falcon research aircraft is characterized for the first time with state-of-the art in situ measurements including sizing instruments operated behind the Falcon aerosol inlet and mounted at the aircraft wing not affected by the aerosol inlet. Sampling efficiencies were derived for different true airspeed ranges by comparing the in-cabin and ”full”-size-range particle number size distributions during 174 flight sequences with a major contribution of mineral dust particles during the ”Absorbing aerosol layers in a changing climate: aging, lifetime and dynamics” project (A-LIFE). Additionally, experimentally derived Stokes numbers were used to calculate the cutoff diameter of the aerosol sampling system for different particle densities as a function of true airspeed. As expected, the results show that the velocity of the research aircraft has a major impact on the sampling of coarse-mode aerosol particles with in-cabin instruments. For true airspeeds up to about 190 m s−1, aerosol particles larger than about 1 µm are depleted in the sampling system of the Falcon during the A-LIFE project. In contrast, for true airspeeds higher than 190 m s−1, an enhancement of particles up to a diameter of 4 µm is observed. For even larger particles, the enhancement effect at the inlet is still present, but inertial and gravitational particle losses in the transport system get more and more pronounced, which leads to a decreasing overall sampling efficiency. In summary, aerosol particles are either depleted or enhanced in the Falcon aerosol inlet, whereas transport in sampling lines always leads to a loss of particles. Here, we have considered both effects and determined the cutoff diameter for the A-LIFE transport system (i.e., the sampling lines only), the cutoff diameter of the Falcon aerosol inlet (i.e., the effect of the inlet only), and the combined effect of the inlet and sampling lines.

Abstract Serpentinites are major carriers of volatiles in deep subduction zones, releasing most fluids in the 500–650°C range. Despite fundamental implications for mass transfer and intermediate‐depth seismicity, the mechanical role of these fluids is unclear. To characterize the mechanical role of fluids at (ultra)high‐pressure conditions, we perform a petro‐structural analysis on olivine‐rich veins from the Western Alps meta‐ophiolite. Some veins formed through dilational and mixed dilational‐shear fracturing without significant shear‐related deformation. However, field and microstructural observations indicate transient shearing and dilational fracturing at high pore fluid pressures. These include: (a) foliated sheared veins; (b) newly formed olivine and Ti‐clinohumite within mineral lineations coating sheared veins and shear bands; (c) Olivine and Ti‐clinohumite mineral fibers sealing porphyroclasts; (d) mutual crosscutting relationships among dilational and shear features. Dilational veins prevail in low‐strain areas, while sheared veins and shear bands dominate within high‐strain zones toward the ultramafic sliver boundaries. These strain variations underscore the role of local stress regimes during serpentinite dehydration. Consequently, areas experiencing stronger shear stresses around large‐scale blocks or mechanical weakening during fluid circulation are prone to draining overpressurized fluids. These interface‐parallel and fracture‐controlled pathways thus facilitate fluid escape from the dehydrating downgoing slab. Transient events of dilational fracturing and brittle‐ductile shearing, along with strain localization in highly comminuted olivine‐bearing sheared veins, may have resulted from strain rate bursts potentially related to (sub)seismic deformation. These observations are in line with geophysical data indicating high pore fluid pressures within the intermediate‐depth seismicity region.

The future TESSERACT experiment will search for individual galactic DM particles below the proton mass through interactions with advanced, ultra-sensitive detectors. Currently TESSERACT is in a design phase aiming to produce fully defined detector technologies that will explore DM masses down to 10 MeV. It is designed to be sensitive to DM candidates interacting with the detector target material in producing both nuclear recoil DM (NRDM) and electron recoil (ERDM). To do so, multiple target materials will be used with varying detection strategies to ensure the capability to both actively reject the so-called low-energy excess and discriminate nuclear recoils against electron recoils. In addition to maximizing sensitivity to a variety of DM interactions, this provides an independent handle on instrumental backgrounds. Nowadays, the TESSERACT project encompasses two US-based technologies, namely HeRALD using superfluid helium as a target material, and SPICE using polar crystals (Al2O3 and SiO2) and scintillating crystals such as GaAs. In these proceedings, we discuss the recent proposal to host the future TESSERACT experiment at the Modane Underground Laboratory (LSM) and add a third French-based cryogenic semiconducting (Ge, Si) detector technology to the TESSERACT payload.

Abstract Background Although physical activity interventions are frequently reported to be effective, long-term changes are needed to generate meaningful health benefits. There are criticisms that evaluations of physical activity interventions mostly report short-term outcomes and that these are often self-reported rather than measured objectively. This study therefore aimed to assess the long-term (at least 24 month) effectiveness of behavioural interventions on objectively measured physical activity. Methods We conducted a systematic review with a meta-analysis of effects on objectively measured physical activity. We searched: Cochrane CENTRAL, EMBASE, PsychInfo, CINAHL and Pubmed up to 10th January 2022. Studies were included if they were in English and included a physical intervention that assessed physical activity in the long-term (defined as at least 24 months). Results Eight studies with 8480 participants were identified with data suitable for meta-analysis. There was a significant effect of interventions on daily steps 24 months post baseline (four studies, SMD: 0.15, 95% CI: 0.02 to 0.28) with similar results at 36 to 48 months of follow up (four studies, SMD: 0.17, 95% CI: 0.07 to 0.27). There was a significant effect of interventions on moderate-to-vigorous physical activity 24 months post baseline (four studies, SMD: 0.18 95% CI: 0.07 to 0.29) and at 36 to 48 months (three studies, SMD: 0.16 95% CI: 0.09 to 0.23). The mean effect size was small. However, the changes in moderate-to-vigorous physical activity and steps per day were clinically meaningful in the best-performing studies. Conclusion This review suggests that behavioural interventions can be effective in promoting small, but clinically meaningful increases in objectively measured physical activity for up to 48 months. There is therefore a need to develop interventions that can achieve greater increases in long-term physical activity with greater efficiency.

INTRODUCTION: Body donation is the willingness of a person to donate his body or organ to a person or organization after death. Medical schools in Western countries depend solely on human donations for medical education. However, the trend is different in Africa due to limited literature. This study aimed to measure the level of knowledge and attitude toward body donation among students at the Huye campus, University of Rwanda METHODS: A cross-sectional study involving 120 students at the Huye campus of the University of Rwanda. Data was collected using a Google format questionnaire. Knowledge and attitude were assigned scores of 0 and 1 for wrong and correct options, respectively. Knowledge of body donation was calculated as the sum of the scores of all knowledge questions, and Attitude was assessed as the mean of the sum of attitude scores. The association of age, knowledge, and attitude was assessed in bivariate analysis with the Chi-square test. The threshold for statistical significance was P ≤ 0.05 with 95% confidence intervals. RESULTS: 49.2% of the respondents had a very good knowledge score, 43.3% had a good knowledge score, 6.7% had a fair knowledge score, and 0.8% had a poor knowledge score. The positive attitude score was 85.8%, and the negative attitude score was 14.2%. However, 66.7% of the respondents showed an unwillingness towards body donation, and 84.2% showed a willingness towards organ donation. CONCLUSION: The unwillingness to donate body organs observed in this study calls for the introduction of sensitization programs or courses on body donation at the tertiary level of education in Rwanda.

INTRODUCTION: Narrowing the gender gap and making education more inclusive are the primary objectives of the government of Rwanda and its stakeholders. However, women are underrepresented in science, technology, and engineering. Fortunately, female medical students have increased steadily in recent years. The objective was to investigate the difference between female and male performance in Anatomy METHODS: The marks of five academic years 2017-2018 to 2021-2022 were used. IBM SPSS Statistics 23 was used to analyze the data. Male and female performance was analyzed based on the general mean scores, then the mean scores of each module, and finally the grade ranges [85%] in five years. The standard deviation and P-values were calculated for difference analysis. RESULTS: 2433 records, 1534 (63.1%) males and 899 (36.9%) females, were pulled out, of which 35 students retook the modules; 19 females and 16 males. 41% of females and 39.6% of males scored between 60-69%, followed by 28.7% of females and 33.5% of males scored between 7084%, 22.5% of females and 20.4% of males scored between 50-59%, and then 6.7% of females and 6.0% of male failed by scoring 85%. CONCLUSION: There is no significant difference between male and female students’ performances in Anatomy when compared (p>0.05). However, efforts should be made to determine the reasons for the gender gap in sciences and also to find means to attract more female students into science-based courses and professions.

The sciatic nerve (SN) presented with unusual patterns in which five smaller fibers instead of one or two nerves at the level of the Piriformis muscle. Those five fibers measured 7.5 cm from their origin to where they joined to form the SN. The SN terminated in the popliteal fossa by giving rise to three terminal branches: the tibial nerve, the common peroneal nerve, and another unusual nerve that supplied the medial head of the gastrocnemius. This case is unusual because the SN presents with different positional variations of its two components in relation to the piriformis muscle but not five fibers; in addition, the SN normally bifurcates instead of trifurcating when it reaches in the popliteal fossa. The case presented a Type A pattern of SN to the piriformis muscle. This type of pattern has been documented to be the most common in some parts of Africa. Some authors have reported two patterns of trifurcation of the SN. One is a pattern where the SN gave rise to the tibial, superficial, and deep peroneal nerves at the popliteal fossa, and another is a trifurcation pattern where it gave rise to the tibial, common peroneal, and sural nerves. The case is different as it presents an unusual unreported pattern where the SN trifurcates by giving rise to the tibial, common peroneal, and nerve that supplies the medial head of the gastrocnemius muscle. The current variation has never been reported elsewhere.

The gluteal region is an important anatomical and clinical area that contains muscles and vital neurovascular bundles. The gluteus maximus is the largest and most powerful muscle in the human body. While there can be some anatomical variations in the gluteus maximus, they are generally minor and do not significantly affect its function; however, its proximity to the sciatic nerve necessitates attention. Hence, a thorough understanding of the gluteal region's anatomy is crucial. In the gluteal region of an adult male cadaver dissection for the postgraduate surgical trainees' regular cadaver dissection course, we discovered a variation of the gluteus maximus muscle that was duplicated with a superficial big portion and a deep small muscle component. The little portion was attached to the hip bone by two tendinous slips connected by a tendinous arch under which the sciatic nerve runs. With this type of anatomical disposition, the sciatic nerve may become entrapped if a small portion of the gluteus muscle hypertrophies, resulting in sciatica. Since the gluteus maximus can entrap the sciatic nerve, understanding the anatomy of the gluteal region is crucial for both anatomical and clinical reasons. Clinicians should be aware of this anatomy for successful surgeries of the gluteal region, intramuscular injections, and dealing with complaints of sciatica. Additional investigation and dissections of the gluteal region are urged for a better comprehension of human anatomy and its variability.

Embryological defects in the development of the kidney cause a unilateral duplicated ureter. It may predispose an individual to the formation of ureteric stones at the junction of the duplicated ureter due to the acute angle formed at the point of union, increasing the likelihood of the “yoyo reflux” phenomenon, urinary stasis, and recurrent urinary tract infections. The case report is a 39-year-old adult male cadaver who had a unilateral duplicated left ureter with a “V” shape at the vesicoureteral junction. The case was discovered during a routine dissection of the abdominal region at the gross anatomy laboratory of the College of Medicine and Health Sciences, University of Rwanda. Although a duplicated ureter may be asymptomatic, it is implicated in the development of ureteric calculi and ureteric infections and increases the susceptibility to potential iatrogenic injury during surgical procedures.

Anatomical variations in humans are widespread but highly complex. A thorough understanding of anatomy is essential for successful surgical and anesthetic procedures. Brachial plexus anatomical variations are prevalent and account for more than 50% of anatomical variations in cadaveric analyses of the human nervous system. Clinical outcomes may be unsatisfactory if specific brachial plexus anatomical variations are overlooked. In 22% of axillary blocks, the musculocutaneous nerve location was found to be irregular. It may be joined to the median nerve and extended distally before disconnecting from it or may be located close to the axillary artery more frequently. Hence, understanding the anatomy of the brachial plexus is necessary for excellent clinical outcomes in upper extremity surgical procedures. We identified a complex left brachial plexus anatomical variation during the upper limbs dissection course. From the lateral cord, two parallel nervous brands emerge as the musculocutaneous nerve and median nerve fusing into the median-musculocutaneous common trunk. Distally, this trunk forms the ansa brachii that gives the nerve to the biceps brachii muscle, the nerve to the brachialis muscle, and the lateral cutaneous nerve of the forearm. Four branches from the lateral cord, the musculocutaneous nerve, and the median-musculocutaneous trunk sequentially innervated the coracobrachialis muscle. Successful upper extremity surgery and anesthesia need a thorough understanding of the human brachial plexus anatomy and its variations. Additional research and dissections are encouraged to understand human anatomy and its variations.

A persistent sciatic artery is an anatomical variation as the artery running in the posterior thigh compartment should have regressed at the embryological level. Its persistence should be looked into the window of potential complications such as aneurysms and limb ischemia. A number of cases have previously been documented in international journals, but none locally. We present findings of a monthly resident dissection course whereby an adult male cadaver was dissected on the gluteal and posterior thigh, and we found a persistent sciatic artery arising on the lateral circumflex femoral artery, and distally, it was joining the normal popliteal artery. Persistent sciatic artery is a variation worth knowing for surgeons and anesthesiologists approaching the posterior thigh. We should foster awareness of such variations through research.

The sciatic nerve is the thickest in the human body; however, it is susceptible to a wide range of anatomical variations with potential clinical implications. Some variations are very rare and unreported in the existing literature We present a case of a middle-aged male cadaver with a sciatic nerve giving a loop where 3 perforator arteries from the profunda femoris artery pass; the loop bundles were reforming the main nerve distally. A sciatic nerve loop engulfing muscular perforator arteries is a scarce anatomical variation worth knowing for clinical, academic, and research interests.

An anterior accessory great saphenous vein (AAGSV) is a major cause of varicose disease recurrence and shares the saphenofemoral junction in 10% of patients where it is a primary reflux pattern. Reflux in AAGSV presents the same symptoms and severity as great saphenous vein (GSV) reflux with a higher incidence of superficial thrombophlebitis. The case report is a 37-year-old male cadaver with bilateral anterior accessory great saphenous veins (AAGSV), originating from the marginal veins anterior to the GSV, and terminated by joining the GSV at the sapheno-femoral junction. The case was documented during a routine gross dissection at the anatomy laboratory at the University of Rwanda. The case emphasizes the need for Vascular radiologists and surgeons to pay proper attention during saphenofemoral junction and saphenopopliteal junction ultrasound to identify the AAGSV when targeting the treatment of varicose diseases.

The left renal vein drains the left kidney to the left lateral inferior vena cava, and it courses anteriorly to the abdominal aorta and posteriorly to the superior mesenteric artery. The case of two renal veins draining the kidneys was seen during a routine dissection of the left retroperitoneal space of a 36-year-old male cadaver. This unusual complex pattern of the left renal vein with an accessory tributary is useful, particularly for surgeons and urologists needing to access the retroperitoneal space. An awareness of such renal vascular variation can help reduce the risk of iatrogenic vascular injury when accessing this area.

The greater saphenous vein (GSV) is a vital structure in the lower extremity with well-documented anatomical variations. This case report describes the unexpected discovery of an accessory GSV during a routine cadaveric dissection at the University of Rwanda's School of Medicine and Pharmacy. The accessory GSV ran parallel to the main GSV before rejoining it higher in the leg. This finding underscores the importance of recognizing anatomical variations like accessory GSVs, which can influence clinical procedures and outcomes. Increased awareness among clinicians and educators is crucial, and further research is needed to assess the prevalence and clinical implications of this rare anatomical variant.

The pre-fusion power operation (PFPO) phase of ITER, as described in the ITER research plan with Staged Approach,22 ITER Organization, “ITER Research Plan within the Staged Approach,” ITR-18–003, Aug. 2018. includes both hydrogen (H) and helium (He) plasma operations. In preparation for PFPO, both WEST and JET ran He plasma campaigns to study plasma-wall interactions in a tungsten environment. The campaigns included a back-and-forth transition between H or deuterium (D) and He plasma operation allowing the assessment of the achievable plasma content as well as the accessible wall reservoirs for respective species. The WEST changeovers included tokamak pulses with a fixed divertor configuration. The JET changeovers applied ion cyclotron wall conditioning (ICWC) and tokamak pulses including limiter phases and four different divertor configurations. Glow discharge conditioning (GDC) was applied to complete the changeovers. The results are characterized by subdivertor optical and mass spectrometric gas analyzers and spatially resolved optical emission spectroscopy. A He content of 96–97 % after H operations is achieved by tens of ICWC pulses (JET) and several dedicated diverted plasmas (WEST and JET), while a fivefold is estimated to be required for the back transition. Effective pumping of the wall released species is a key parameter for a fast changeover. Upon applying higher heating power, the relative content of the fueled plasma species decreases. The JET gas balance analysis indicates that He operation may increase H retention. WEST divertor spectroscopy indicates a larger He inventory near the inner divertor strike line. He GDC has a clear effect on the He recycling light at the WEST divertor while D GDC did not reduce the long lasting He content observed in D pulses after the JET He campaign.

Resume: Introducción: Las ataxias (AT) y paraparesias espásticas hereditarias (PEH) son síndromes neurodegenerativos raros. Nos proponemos conocer la prevalencia de las AT y PEH en España en 2019. Pacientes y métodos: Estudio transversal, multicéntrico, descriptivo y retrospectivo de los pacientes con AT y PEH, desde marzo de 2018 a diciembre de 2019 en toda España. Resultados: Se obtuvo información de 1933 pacientes procedentes de 11 Comunidades Autónomas, de 47 neurólogos o genetistas. Edad media: 53,64 años ± 20,51 desviación estándar (DE); 938 varones (48,5%), 995 mujeres (51,5%). En 920 pacientes (47,6%) no se conoce el defecto genético. Por patologías, 1.371 pacientes (70,9%) diagnosticados de AT, 562 diagnosticados de PEH (29,1%). La prevalencia estimada de AT es 5,48/100.000 habitantes, y la de PEH es 2,24 casos/100.000 habitantes. La AT dominante más frecuente es la SCA3. La AT recesiva más frecuente es la ataxia de Friedreich (FRDA). La PEH dominante más frecuente es la SPG4, y la PEH recesiva más frecuente es la SPG7. Conclusiones: La prevalencia estimada de AT y PEH en nuestra serie es de 7,73 casos/100.000 habitantes. Estas frecuencias son similares a las del resto del mundo. En el 47,6% no se ha conseguido un diagnóstico genético. A pesar de las limitaciones, este estudio puede contribuir a estimar los recursos, visibilizar estas enfermedades, detectar las mutaciones más frecuentes para hacer los screenings por comunidades, y favorecer los ensayos clínicos. Abstract: Introduction: Ataxia and hereditary spastic paraplegia are rare neurodegenerative syndromes. We aimed to determine the prevalence of these disorders in Spain in 2019. Patients and methods: We conducted a cross-sectional, multicentre, retrospective, descriptive study of patients with ataxia and hereditary spastic paraplegia in Spain between March 2018 and December 2019. Results: We gathered data from a total of 1933 patients from 11 autonomous communities, provided by 47 neurologists or geneticists. Mean (SD) age in our sample was 53.64 (20.51) years; 938 patients were men (48.5%) and 995 were women (51.5%). The genetic defect was unidentified in 920 patients (47.6%). A total of 1371 patients (70.9%) had ataxia and 562 (29.1%) had hereditary spastic paraplegia. Prevalence rates for ataxia and hereditary spastic paraplegia were estimated at 5.48 and 2.24 cases per 100 000 population, respectively. The most frequent type of dominant ataxia in our sample was SCA3, and the most frequent recessive ataxia was Friedreich ataxia. The most frequent type of dominant hereditary spastic paraplegia in our sample was SPG4, and the most frequent recessive type was SPG7. Conclusions: In our sample, the estimated prevalence of ataxia and hereditary spastic paraplegia was 7.73 cases per 100 000 population. This rate is similar to those reported for other countries. Genetic diagnosis was not available in 47.6% of cases. Despite these limitations, our study provides useful data for estimating the necessary healthcare resources for these patients, raising awareness of these diseases, determining the most frequent causal mutations for local screening programmes, and promoting the development of clinical trials.

Introduction: Ataxia and hereditary spastic paraplegia are rare neurodegenerative syndromes. We aimed to determine the prevalence of these disorders in Spain in 2019. Patients and methods: We conducted a cross-sectional, multicentre, retrospective, descriptive study of patients with ataxia and hereditary spastic paraplegia in Spain between March 2018 and December 2019. Results: We gathered data from a total of 1933 patients from 11 autonomous communities, provided by 47 neurologists or geneticists. Mean (SD) age in our sample was 53.64 (20.51) years; 938 patients were men (48.5%) and 995 were women (51.5%). The genetic defect was unidentified in 920 patients (47.6%). A total of 1371 patients (70.9%) had ataxia and 562 (29.1%) had hereditary spastic paraplegia. Prevalence rates for ataxia and hereditary spastic paraplegia were estimated at 5.48 and 2.24 cases per 100 000 population, respectively. The most frequent type of dominant ataxia in our sample was SCA3, and the most frequent recessive ataxia was Friedreich ataxia. The most frequent type of dominant hereditary spastic paraplegia in our sample was SPG4, and the most frequent recessive type was SPG7. Conclusions: In our sample, the estimated prevalence of ataxia and hereditary spastic paraplegia was 7.73 cases per 100 000 population. This rate is similar to those reported for other countries. Genetic diagnosis was not available in 47.6% of cases. Despite these limitations, our study provides useful data for estimating the necessary healthcare resources for these patients, raising awareness of these diseases, determining the most frequent causal mutations for local screening programmes, and promoting the development of clinical trials. Resumen: Introducción: Las ataxias (AT) y paraparesias espásticas hereditarias (PEH) son síndromes neurodegenerativos raros. Nos proponemos conocer la prevalencia de las AT y PEH (APEH) en España en 2019. Pacientes y métodos: Estudio transversal, multicéntrico, descriptivo y retrospectivo de los pacientes con AT y PEH, desde Marzo de 2018 a Diciembre de 2019 en toda España. Resultados: Se obtuvo información de 1.933 pacientes procedentes de 11 Comunidades Autónomas, de 47 neurólogos o genetistas. Edad media: 53,64 años ± 20,51 desviación estándar (DE); 938 varones (48,5%), 995 mujeres (51,1%). En 920 pacientes (47,6%) no se conoce el defecto genético. Por patologías, 1.371 pacientes (70,9%) diagnosticados de AT, 562 diagnosticados de PEH (29,1%). La prevalencia estimada de AT es 5,48/100.000 habitantes, y la de PEH es 2,24 casos/100.000 habitantes. La AT dominante más frecuente es la SCA3. La AT recesiva más frecuente es la ataxia de Friedreich (FRDA). La PEH dominante más frecuente es la SPG4, y la PEH recesiva más frecuente es la SPG7. Conclusiones: La prevalencia estimada de APEH en nuestra serie es de 7,73 casos/100.000 habitantes. Estas frecuencias son similares a las del resto del mundo. En el 47,6% no se ha conseguido un diagnóstico genético. A pesar de las limitaciones, este estudio puede contribuir a estimar los recursos, visibilizar estas enfermedades, detectar las mutaciones más frecuentes para hacer los screenings por comunidades, y favorecer los ensayos clínicos.