Axial Dimensions Research Articles

Predicting the onset of myopia in children by age, sex, and ethnicity: Results from the CLEERE Study.

Clinicians and researchers would benefit from being able to predict the onset of myopia for an individual child. This report provides a model for calculating the probability of myopia onset, year-by-year and cumulatively, based on results from the largest, most ethnically diverse study of myopia onset in the United States. This study aimed to model the probability of the onset of myopia in previously nonmyopic school-aged children. Children aged 6 years to less than 14 years of age at baseline participating in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study who were nonmyopic and less hyperopic than +3.00 D (spherical equivalent) were followed up for 1 to 7 years through eighth grade. Annual measurements included cycloplegic autorefraction, keratometry, ultrasound axial dimensions, and parental report of children's near work and time spent in outdoor and/or sports activities. The onset of myopia was defined as the first visit with at least -0.75 D of myopia in each principal meridian. The predictive model was built using discrete time survival analysis and evaluated with C statistics. The model of the probability of the onset of myopia included cycloplegic spherical equivalent refractive error, the horizontal/vertical component of astigmatism (J0), age, sex, and race/ethnicity. Onset of myopia was more likely with lower amounts of hyperopia and less positive/more negative values of J0. Younger Asian American females had the highest eventual probability of onset, whereas older White males had the lowest. Model performance increased with older baseline age, with C statistics ranging from 0.83 at 6 years of age to 0.92 at 13 years. The probability of the onset of myopia can be estimated for children in the major racial/ethnic groups within the United States on a year-by-year and cumulative basis up to age 14 years based on a simple set of refractive error and demographic variables.

Comprehensive theoretical and experimental study of plasma plume dynamics across magnetic field

Dynamics of laser-produced plasma plume in the presence of magnetic field has been investigated theoretically and experimentally. A mathematical model has been proposed to estimate the time variation of axial dimension, expansion velocity and effective deceleration of the plasma plume across the magnetic field. The numerical solutions are also verified with analytical solutions. In order to validate the theoretical model, two directional, time-resolved images of laser-produced nickel and tungsten plasmas have been recorded in different magnetic field. The simulated plasma dynamics is compared with experimental data for significantly different atomic masses of ablated species, expand in wide range of magnetic field, ranging from 0.1 to 0.5 T. Most of the dynamical features for the both, diamagnetic and beyond the diamagnetic region e.g., temporal variation of plume dimension, characteristic time duration of diamagnetic behaviour, bubble radius and plasma instability are well captured by theoretical model with reasonable agreement with experimental observations.

Long term follow-up of axial length and orbital dimensions in congenital microphthalmia and anophthalmia.

To evaluate axial length (AL), orbital width (OW) and height (OH) development in congenital microphthalmia and anophthalmia (MICA) using serial ultrasonography measurements. A longitudinal prospective cohort (n = 74) of unilaterally and bilaterally affected MICA patients was followed from 2013 to 2022 at the university hospital in Amsterdam, the Netherlands. Clinical entity, age, severity category based on axial length, conformer treatment and intra-orbital cysts were registered. The main outcome measures were the absolute and relative growth of AL, OW and OH. Surgical and intra-orbital cyst cases were described separately. Absolute microphthalmic eye size increased in 27/49 (55%) unilateral MICA eyes, but growth arrest/decrease in the remaining could shift the case to a more severe category over time. A final affected/unaffected orbital symmetry ≥80% was seen in the large majority of unilateral cases (45/46 for OW, 43/46 for OH). Cases with AL < 10.5 mm had orbital symmetry <80% more often. Most orbital symmetry changes were seen in moderate and severe unilateral cases treated with 3D-printed conformer therapy starting at age <1 year, with 6/10 (60%) symmetry increase, 30% unchanged symmetry and 10% symmetry decrease. All cases older than 6.5 years (n = 6) did not show any change anymore, regardless of treatment. For bilateral and unilateral mild cases, orbital dimensions kept the same proportions during follow-up, with or without conformer treatment. Using severity categories in MICA based on relative AL may aid the decision to start conformer treatment, as most orbital symmetry changes were seen in moderate and severe unilateral cases receiving 3D-printed conformer therapy that started under age 1.

User-friendly oblique plane microscopy on a fully functional commercially available microscope base.

In this work we present an oblique plane microscope designed to work seamlessly with a commercially available microscope base. To support all the functionality offered by the microscope base, where the position of the objective lens is not fixed, we adopted a two-mirror scanning geometry that can compensate for changes to the position of the objective lens during routine microscope operation. We showed that within a ± 1 mm displacement range of the 100X, 1.35 NA objective lens away from its designed position, the PSF size increased by <3% and <11% in the lateral and axial dimensions, respectively, while the error in magnification was <0.5% within volumes extending ± 10 µm about the focal plane. Compared to the more traditional scan-lens/galvo-mirror combination, the two-mirror scanning geometry offers higher light efficiency and a more compact footprint, which could be beneficial to all OPM designs regardless of the use of a commercial base or not.

Optimization of 3D Passive Acoustic Mapping Image Metrics: Impact of Sensor Geometry and Beamforming Approach.

Three-dimensional passive acoustic mapping (PAM) with matrix arrays typically suffers from high demands on the receiving electronics and high computational load. In our study, we investigated, both numerically and experimentally, the influence of matrix array aperture size, element count, and beamforming approaches on defined image metrics. With a numerical Vokurka model, matrix array acquisitions of cavitation signals were simulated. In the experimental part, two 32 × 32 matrix arrays with different pitches and aperture sizes were used. After being reconstructed into 3D cavitation maps, defined metrics were calculated for a quantitative comparison of experimental and numerical data. The numerical results showed that the enlargement of the aperture from 5 to 40 mm resulted in an improvement of the full width at half maximum (FWHM) by factors of 6 and 13 (in lateral and axial dimension, respectively). A larger array sparsity influenced the point spread function (PSF) only slightly, while the grating lobe level (GLL) remained more than 12 dB below the main lobe. These results were successfully experimentally confirmed. To further reduce the GLL caused by array sparsity, we adapted a non-linear filter from optoacoustics for use in PAM. In combination with the delay, multiply, sum, and integrate (DMSAI) algorithm, the GLL was decreased by 20 dB for 64-element reconstructions, resulting in levels that were identical to the fully populated matrix reconstruction levels.

Magnetic Field Analysis and Development of Disk Axial–Radial Hybrid Excitation Generator for Range Extenders in Extended-Range Electric Vehicles

Magnetic Field Analysis and Development of Disk Axial–Radial Hybrid Excitation Generator for Range Extenders in Extended-Range Electric Vehicles

Ag2S-Decorated One-Dimensional CdS Nanorods for Rapid Detection and Effective Discrimination of n-Butanol.

N-butanol (C4H9OH) is a volatile organic compound (VOC) that is susceptible to industrial explosions. It has become imperative to develop n-butanol sensors with high selectivity and fast response and recovery kinetics. CdS/Ag2S composite nanomaterials were designed and prepared by the solvothermal method. The incorporation of Ag2S engendered a notable augmentation in specific surface area and a consequential narrow band gap. The CdS/Ag2S-based sensor with 3% molar ratio of Ag2S, operating at 200 °C, demonstrated a remarkably elevated response (S = Ra/Rg = 24.5) when exposed to 100 ppm n-butanol, surpassing the pristine CdS by a factor of approximately four. Furthermore, this sensor exhibited notably shortened response and recovery times, at a mere 4 s and 1 s, respectively. These improvements were ascribed to the one-dimensional single-crystal nanorod structure of CdS, which provided an effective path for expedited electron transport along its axial dimension. Additionally, the electron and chemical sensitization effects resulting from the modification with precious metal sulfides Ag2S were the primary reasons for enhancing the sensor response. This work can contribute to mitigating the safety risks associated with the use of n-butanol in industrial processes.

Integrated design and hydraulic model optimization of model horizontal main pump based on CFD fluid dynamics analysis

There are few studies and reports related to horizontal main pumps for nuclear power plants. The installation of vertical main pumps for small reactors requires the design of special elbows on the pressure vessel. Horizontal main pump, as a new main pump structure, can reduce the diameter of the main pressure vessel and simplify the structure of the pressure vessel. Compared with the vertical main pump, the horizontal main pump needs to control its axial dimension to improve its stiffness, which makes it impossible to set a long straight pipe section at the inlet, which has an impact on the pump performance. On the other hand, the compression of the axial dimension of the pump casing makes the overflow area of the press-out chamber small, resulting in large hydraulic losses. In this paper, in order to improve the efficiency of the pump and reduce the influence of non-uniform incoming flow, the optimization design is carried out with the SST k-ω model, and it is shown that: 1. the suction port of the curved impeller is easier for the fluid to enter into the impeller in the axial direction; and 2. the axially symmetric worm gear produces more vortex flow losses.

Synchronous myopia development induced by bilateral form deprivation in chicks

Form deprivation (FD) is a widely employed experimental paradigm, typically used to induce unilateral myopia in animal models. This model is weakened by potential influence upon the FD eye from vision in the freely-viewing contralateral eye, which could be eliminated by imposing FD in both eyes; but while a few previous studies have explored the feasibility of inducing bilateral FD in chicks, substantial discrepancies in treatment outcomes were noted. Consequently, this study aimed to establish a bilateral FD myopia model in chicks, with validation by investigating the associated ocular growth patterns, feeding, and social behavior. Six-day-old chicks were treated with bilateral (n = 21) or unilateral (n = 10) FD for 12 days; the fellow untreated eyes in the unilateral FD group served as controls. Refractive error, corneal power, and ocular axial dimensions were measured at 4-day intervals after the onset of form deprivation, with a Hartinger refractometer, a custom-made videokeratography system, and a high-resolution A-scan ultrasonographer, respectively. Body weight was monitored to assess the chick's physical development. Our results showed that birds treated with bilateral FD grew as robustly as the unilaterally form-deprived chicks, with similar or slightly heavier body weights and mortalities. Unilateral FD induced significantly higher myopia in the treated eye, with stronger corneal power, deeper anterior and vitreous chambers, and longer axial length. Moreover, either bilaterally or unilaterally FD eyes developed similar refractive error (bilateral FD, left: −28.03 ± 9.06 D, right: −28.44 ± 9.45 D; unilateral FD: −29.48 ± 8.26 D) and ocular biometric changes; but choroidal thickness was thicker in bilaterally FD eyes, rather than thinner as in unilaterally FD eyes. In addition to the highly synchronized (symmetrical, parallel) development reported previously in bilateral FD, we found in this study that the correlations between bilaterally form-deprived eyes were highest for ocular biometric parameters directly contributing to myopia development, including corneal power (r = 0.74 to 0.93), anterior chamber depth (r = 0.60 to 0.85), vitreous chamber depth (r = 0.92 to 0.94), and axial length (r = 0.90 to 0.96). The remarkably synchronized growth pattern confirmed the feasibility of the bilateral FD paradigm for future research on myopia.

Altered corneal structures in form‐deprived highly myopic chicks

Aims/Purpose: Myopia is a leading cause of correctable and preventable vision loss worldwide, but the relationship between myopia development and growth of the anterior segment, particularly the cornea, has not been well established. This study aims to investigate whether experimental induction of myopia influences corneal structures in animals.Methods: Ten chicks were unilaterally form deprived by covering their right eyes with translucent diffusers at post‐hatching day 6 (P6). Refractive state, corneal shape, and ocular axial dimensions were measured at 4‐day intervals until P18 using a Hartinger refractometer, a custom‐made videokeratography system, and an A‐scan ultrasonographer, respectively. Parameters in treated vs control eyes were compared at the end of treatment. Repeated one‐way ANOVA was used for statistical analysis, and all parameters were expressed as mean ± SD.Results: At the end of treatment, form‐deprived eyes were myopic (−29.48 ± 8.26D vs. ‐0.61 ± 0.32D) and axially elongated (11.15 ± 0.55 mm vs. 9.51 ± 0.20 mm). At baseline (P6), treated and fellow contralateral eyes had similar corneal power (132.22 ± 6.37D vs. 132.64 ± 5.48D, p = 0.86) and thickness (167.93 ± 6.80 μm vs. 166.43 ± 7.27 μm, p = 0.63), but at P18 form‐deprived eyes had slower corneal flattening and thickening, resulting in significantly steeper (117.73 ± 5.03D vs. 113.22 ± 3.44D, p &lt; 0.05) and thinner corneas (176.80 ± 7.52 μm vs. 192.35 ± 5.62 μm, p &lt; 0.001) than fellow contralateral eyes. Repeated measures correlation analysis further indicated that axial elongation from P6 to P18 was significantly associated with corneal steepening (rrm = 0.77, p &lt; 0.001) and thinning (rrm = −0.69, p &lt; 0.001).Conclusions: This study provides insights into the impact of form deprivation myopia on corneal structures in juvenile animals. Specifically, the corneas of form‐deprived eyes were steeper and thinner because the natural corneal flattening and thickening processes were decelerated by treatment. Further studies are warranted to reveal the mechanisms responsible for this association between development of refractive error and corneal structure.

Impact of ingenious pre-treatments on performance indices and dimensional properties of kodo millet

The present study focussed on standardisation of suitable method for kodo dehulling and evaluated the outcome percentage of dehulled kodo millet. A combination of abrasive and centrifugal type of dehulling and hydrothermal treatment followed by centrifugal dehulling was applied on whole kodo millet. Only centrifugal dehulled millet was taken as control. Dehulling index, Coefficient of dehulling, degree of dehulling and overall dehulling efficiency was more compared to control samples. Principal axial dimensions, dimensional parameters such as sphericity, aspect ratio, geometric and arithmetic mean diameter was calculated and had significant difference between control and experimental samples.

Preliminary treatments of Browntop and effect on performance indices, physical and geometrical properties of grain

In the present study Browntop (BT) millet was subjected to three different treatments viz., mechanical stress, hydrothermal treatment and combined treatment (mechanical and hydrothermal) to enhance the dehulling efficiency and studied for its performance indices and its impact on physical, grain dimensions and therefore geometrical dimensions. Different treatments on grain before dehulling has shown significant improvement in the dehulling index up to 93%, coefficient of dehulling up to 96.88 %, and overall dehulling efficiency up to 96.73% compared to control. Principal axial dimensions, physical properties, and geometrical parameters of the produce were calculated to evaluate the grain vulnerability to the above treatments. Bulk Density and true density resulted in no significant difference between control and treated samples of browntop millet whereas porosity had significant difference. Principal dimensions such as length, width and thickness had not differed significantly in browntop millet. Geometric dimensions of browntop millet such as GMD, AMD, slenderness ratio, aspect ratio, sphericity, surface area and volume were evaluated and had no significant difference for control and treated samples except for volume of the grain(p&lt;0.01). Thus the study revealed that preliminary treatments had shown significant impact on dehulling efficiency without disrupting physical properties, grain dimensions and geometric parameters

Management of tumor volume changes during preoperative radiotherapy for extremity soft tissue sarcoma: a new strategy of adaptive radiotherapy.

Using adaptive radiotherapy (ART), to determine objective clinical criteria that identify extremity soft tissue sarcoma (ESTS) patients requiring adaptation of their preoperative radiotherapy (RT) plan. We included 17 patients with a lower extremity ESTS treated between 2019 and 2021 with preoperative RT, using helicoidal intensity-modulated RT (IMRT) tomotherapy, before surgical resection. We collected clinical, tumor parameters and treatment data. Repositioning was ascertained by daily Megavoltage computed tomography (MVCT) imaging. Using the PreciseART technology we retrospectively manually delineated at least one MVCT for each patient per week and recorded volume and dosimetric parameters. A greater than 5% change between target volume and planned target volume (PTV) dosimetric coverage from the initial planning CT scan to at least one MVCT was defined as clinically significant. All 17 patients experienced significant tumor volume changes during treatment; 7 tumors grew (41%) and 10 shrank (59%). Three patients (18%), all undifferentiated pleomorphic sarcomas (UPS) with increased volume changes, experienced significant reductions in tumor dose coverage. Seven patients required a plan adaptation, as determined by practical criteria applied in our departmental practice. Among these patients, only one ultimately experienced a significant change in PTV coverage. Three patients had a PTV decrease of coverage. Among them, 2 did not receive plan adaptation according our criteria. None of the patients with decreased tumor volumes had reduced target volume coverage. Monitoring volume variations by estimating gross tumor volume (GTV) on MVCT, in addition to axial and sagittal linear tumor dimensions, appeared to be most effective for detecting reductions in PTV coverage throughout treatment. Variations in ESTS volume are evident during preoperative RT, but significant dosimetric variations are rare. Specific attention should be paid to grade 2-3 UPSs during the first 2 weeks of treatment. In the absence of dedicated software in routine clinical practice, monitoring of tumor volume changes by estimating GTV may represent a useful strategy for identifying patients whose treatment needs to be replanned.

Stereotactic Radiosurgery for Vestibular Schwannoma With Radiographic Brainstem Compression.

The safety of single-treatment stereotactic radiosurgery (SRS) for vestibular schwannoma (VS) with radiographic evidence of brainstem compression but without motor deficit is controversial. Data on linear accelerator (linac)-based SRS in this setting are scarce. We address this with an outcomes report from an unselected series of patients with VS with radiographic brainstem compression treated with linac SRS. We included 139 patients with unilateral VS (any size) with radiographic brainstem compression (all without serious brainstem neurological deficits). The SRS prescription dose was 12.5Gy (single fraction) using 6MV linac-produced photon beams, delivered with a multiple arc technique. Inclusion criteria required at least 1 year of radiographic follow-up with magnetic resonance imaging. The primary endpoint was freedom from serious brainstem toxicity (≥grade 3 Common Terminology Criteria for Adverse Events v5); the secondary was freedom from enlargement (tumor progression or any requiring intervention). We assessed serious cranial nerve complications, excluding hearing loss, defined as Common Terminology Criteria for Adverse Events v5 grade 3 toxicity. Median magnetic resonance imaging follow-up time was 5 years, and median tumor size was 2.5cm in greatest axial dimension and 5ml in volume. The median brainstem D0.03ml=12.6Gy and median brainstem V10Gy=0.4ml. At 5 years, the actuarial freedom from serious brainstem toxicity was 100%, and freedom from tumor enlargement (requiring surgery and/or due to progression) was 90%. Severe facial nerve damage in patients without tumor enlargement was 0.9%. Linac-based SRS, as delivered in our series for VS with radiographic brainstem compression, is safe and effective.

RADT-22. STEREOTACTIC RADIOSURGERY FOR VESTIBULAR SCHWANNOMA WITH RADIOGRAPHIC BRAINSTEM COMPRESSION

Abstract BACKGROUND The safety of single treatment stereotactic radiosurgery (SRS) for vestibular schwannoma (VS) with radiographic evidence of brainstem compression- but without motor deficit- is controversial. Data on linac-based SRS in this setting are scarce. We address this deficit in the literature with a report of outcome of an unselected series of patients with VS with radiographic brainstem compression treated with linac SRS our institution. METHODS We included patients with unilateral VS of any size with radiographic brainstem compression at the time of SRS. All patients were without serious brainstem neurologic deficits at the time of SRS. The SRS prescription dose was 12.5 Gy in a single fraction using 6MV photon beams produced by a linear accelerator and delivered with a multiple arc technique. Inclusion in this study required at least 1 year of radiographic follow-up with magnetic resonance imaging (MRI). The primary endpoint was freedom from serious brainstem toxicity (CTCAEv5 grade &amp;gt;3); secondary endpoint was freedom from tumor enlargement considered to represent tumor progression, or any type of enlargement requiring surgical intervention. We also assessed serious cranial nerve complications, excluding hearing loss, defined as CTCAEv5 grade 3 toxicity. RESULTS Among 139 patients, the median MRI follow-up time was 5 years and the median tumor size was 2.5 cm greatest axial dimension and 5cc in volume. The median brainstem D0.03cc = 12.6 Gy, and the median brainstem V10Gy = 0.4cc. At 5 years, the actuarial freedom from serious brainstem toxicity was 100% (zero cases), and freedom from tumor enlargement, either requiring surgery or due to progression, was 90%. The rate of grade 3 facial nerve damage in patients without tumor enlargement was 0.9% (1/113). CONCLUSION Linac-based SRS as delivered in our series for VS with radiographic brainstem compression is safe and effective.

Integrative Transcriptome and Proteome Analyses Elucidate the Mechanism of Lens-Induced Myopia in Mice.

The purpose of this study was to investigate the underlying molecular mechanism of lens-induced myopia (LIM) through transcriptome and proteome analyses with a modified mouse myopia model. Four-week-old C57BL/6J mice were treated with a homemade newly designed -25 diopter (D) lens mounting by a 3D printing pen before right eyes for 4 weeks. Refraction (RE) and axial dimensions were measured every 2 weeks. Retinas were analyzed by RNA-sequencing and data-independent acquisition liquid chromatography tandem mass spectrometry. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation, and STRING databases were used to identify significantly affected pathways in transcriptomic and proteomic data sets. Western blot was used to detect the expression of specific proteins. The modified model was accessible and efficient. Mice displayed a significant myopic shift (approximately 8 D) following 4 weeks' of lens treatment. Through transcriptomics and proteomics analysis, we elucidated 175 differently expressed genes (DEGs) and 646 differentially expressed proteins (DEPs) between binoculus. The transcriptomic and proteomic data showed a low correlation. Going over the mRNA protein matches, insulin like growth factor 2 mRNA binding protein 1 (Igf2bp1) was found to be a convincing biomarker of LIM, which was confirmed by Western blot. RNA-seq and proteome profiling confirmed that these two "omics" data sets complemented one another in KEGG pathways annovation. Among these, metabolic and human diseases pathways were considered to be correlated with the LIM forming process. The newly constructed LIM model provides a useful tool for future myopia research. Combining transcriptomic and proteomic analysis may potentially brighten the prospects of novel therapeutic targets for patients with myopia.

Modeling Gamma Knife Radiosurgical Toxicity for Multiple Brain Metastases

Dosing for single fraction radiosurgery has traditionally relied on tumor measurements from a single maximum diameter. Most protocols recommend setting dosing criteria based on assumed risk of radionecrosis roughly correlating with tumor size. However, the risk of radionecrosis after radiosurgery is best modeled by a function of dose and volume treated, with the largest body of evidence supporting the use of brain tissue receiving ≥12 Gy in one fraction (V12, i.e., > 10.9 cm3). Here we show that tumor surface area (SA) and second order dimensions are superior predictors for Gamma Knife radiosurgical toxicity and can be used to estimate V12. A total of 1217 brain metastases from 245 patients treated with a prescribed dose from 13 to 27 Gy in one fraction were retrospectively reviewed. Eight independent modeling parameters were considered; 3 geometric tumor characteristics: SA, volume (V), and largest axial dimension (LAD) and 5 treatment planning variables: prescription dose (Rx), coverage, selectivity, gradient index, and number of shots. Linear regression and power-law formulations were performed to determine which parameters were the most accurate predictors of V12. The power model is dependent on a conceptualized "pseudo surface area" (PSA), defined as the surface area of a sphere with a diameter of LAD of a lesion (PSA = π*LAD2). At the aggregate patient level, the model predicts total brain V12 by summing the V12 values for each singular lesion only by using LAD and Rx as input variables. Tumor SA was the best univariate linear predictor of V12 (adjR2 = 0.770), followed by LAD (adjR2 = 0.755) and V (adjR2 = 0.745). The SA predictive model improves for lesions that have high sphericity > 0.85 (adjR2 = 0.837), with a measure of 1 indicating a perfect sphere. Using bivariable regression analysis, we formulated a single term power model that even more accurately predicts for V12 (V12 = 0.0137 * Rx1.5 * LAD2, adjR2 = 0.906) and is proportional to PSA. At the patient level, this model also accurately predicts for total brain V12 (adjR2 = 0.896) and V12 > 10.9 cm3 (Sensitivity = 99.1%, Specificity = 90.5%). Conceptually, SA univariately predicts for V12 more accurately than other tumor physical dimensions or treatment planning parameters, while the best bivariable power model involves PSA. We provide a preplan model for brain metastases that can help better estimate radionecrosis risk, determine prescription doses given a target V12, and provide safe dose escalation strategies without the use of any planning software.

Moisture dependent postharvest physical and textural characteristics of brown sesame seed (var. TMV-4)

Physical and textural characteristics are important in design and manufacturing of harvest and post harvest machines. Some postharvest physical and textural characteristics of brown sesame seed (var. TMV-4) were determined as a function of moisture content in the range of 4.3 per cent to 20 per cent (d.b). The axial dimensions, geometric mean diameter, surface area, volume, sphericity and aspect ratio were found to be increasing linearly for all studied moisture levels. Furthermore, the thousand seed mass, true density, porosity and the angle of repose also increased linearly whereas, bulk density decreased linearly with the increase of moisture content under study. The results showed that the static coefficient of friction on four different surfaces of plywood, mild steel, galvanized iron and glass also increased linearly for all level of moisture. The initial cracking force, average rupture force and average rupture energy decreased linearly with increased moisture content of 4.3 to 20 per cent (d.b.).

Near index matching enables solid diffractive optical element fabrication via additive manufacturing

Diffractive optical elements (DOEs) have a wide range of applications in optics and photonics, thanks to their capability to perform complex wavefront shaping in a compact form. However, widespread applicability of DOEs is still limited, because existing fabrication methods are cumbersome and expensive. Here, we present a simple and cost-effective fabrication approach for solid, high-performance DOEs. The method is based on conjugating two nearly refractive index-matched solidifiable transparent materials. The index matching allows for extreme scaling up of the elements in the axial dimension, which enables simple fabrication of a template using commercially available 3D printing at tens-of-micrometer resolution. We demonstrated the approach by fabricating and using DOEs serving as microlens arrays, vortex plates, including for highly sensitive applications such as vector beam generation and super-resolution microscopy using MINSTED, and phase-masks for three-dimensional single-molecule localization microscopy. Beyond the advantage of making DOEs widely accessible by drastically simplifying their production, the method also overcomes difficulties faced by existing methods in fabricating highly complex elements, such as high-order vortex plates, and spectrum-encoding phase masks for microscopy.

Measures of morphological complexity of microalgae and their linkage with organism size

In phytoplankton ecology the shape of microalgae appears predominantly as a categorical variable. Using shape-realistic 3D models of 220 microalgae we proposed and calculated six shape metrics and tested how these relate to each other and to the size of the microalgae. We found that some of the metrics are more sensitive to elongation, while others are related to multicellularity. We found a linear relationship between shape measures and the greatest axial linear dimensions of the microalgae. Our findings suggest that there is an evolutionary trade-off between the shape and size of the microalgae. It is important to stress that we found that surface area to volume ratio of the microalgae are hyperbolic functions of the length and volume for each shape. In our study, we demonstrated that the proposed shape metrics serve as suitable quantitative traits, and help to understand better how simple shapes evolved to more complex outlines.