Net-like Pattern Research Articles

Bark anatomy of Pteroceltis tatarinowii, Cannabaceae

Summary Pteroceltis tatarinowii, a tertiary relic plant, has a long and fascinating history in China due to its irreplaceable role in traditional papermaking. In this study, the anatomical differences between young and old bark were analysed by light microscopy (LM), fluorescence microscopy (FM), and polarized light microscopy (PLM). Both the young and old bark contain periderm, cortex, and phloem. In the non-conducting phloem, the curved radial phloem rays were perpendicular to bands of sieve-tube elements and axial parenchyma cells, forming a net-like pattern. Primary phloem fibres only occurred in young bark, and both primary and secondary phloem fibres contained a gelatinous layer (G-layer). Transmission electron microscopy (TEM) showed that the thickness of the G-layer in the primary phloem fibres was about 1.5–4 times higher than that of the secondary phloem fibres. The thick G-layer might be an important potential reason for the absorption of ink by paper made from P. tatarinowii phloem fibres, due to the good water absorption of the gelatinous layer.

Prototype of Melon Fruit Quality Sorter Based on Skin Texture Using Local Binary Pattern Histogram

Cucumis Melo L is one of the popular fruits in Indonesia. The numerous benefits and various contents of melon make it highly valuable for human health. Determining the quality of melon is crucial, considering its numerous benefits and contents. The quality of melon is determined by the presence of net-like patterns on the surface of the fruit's skin when it is ripe for harvest. Currently, conventional methods that rely on direct visual observation are still commonly used to sort the quality of melons. Therefore, a prototype system was developed to sort the quality of melons based on the texture of their skin. The purpose of this system is to reduce errors caused by eye fatigue and variations in accuracy during the sorting process. In this research, the feature extraction method of the local binary pattern (LBP) was employed, along with the K-Nearest Neighbor (KNN) method for classification. The classification was divided into two grades: Grade A and Grade B melons. The testing phase involved 200 data samples, with each grade consisting of 100 data samples. The results of the testing phase showed a success rate of 96% for the system. Based on the percentage, it can be concluded that the system has successfully performed well in sorting the quality of melons based on the texture of their skin.

Co-existent Dowling–Degos disease, reticulate acropigmentation of Kitamura, and acropigmentation of Dohi in two generations: An overlap or concept of a single disease?

Reticulate pigmentary disorders (RPDs) are a group of rare autosomal dominant dermatoses with a distinctive clinical net-like pattern with specific arrangements and distributions in each entity. A forty-year-old female presented with asymptomatic, light and dark, macular lesions existing for over fifteen years with perioral scars and palmer pits and her twenty-year-old daughter beginning to develop similar lesions four years earlier. Cutaneous and histopathological examinations suggested a diagnosis of Dowling–Degos disease co-existent with reticulate acropigmentation of Kitamura in the mother and Dowling–Degos disease co-existent with acropigmentation of Dohi in the daughter. The co-existence of three infrequently encountered dermatoses with an irregular disease presentation within the family suggested the possibility of differing entities in the reticulate pigmentary group of disorders belonging to the diverse spectrums of the same disease. Key words: Reticulate pigmentary disorders, Dowling–Degos disease, Reticulate acropigmentation of Kitamura, Reticulate acropigmentation of Dohi

Reticular Epithelial Edema in a Postkeratoplasty Eye Due to Ripasudil.

A 34-year-old female underwent phacoemulsification with Descemet stripping endothelial keratoplasty (Supplementary Digital Content, Fig. 1A, B, http://links.lww.com/APJO/ A132) under a failed previous therapeutic penetrating keratoplasty. The visual acuity was restored to 20/50. At 2 years postoperative period, she developed raised intraocular pressure of 30 mm Hg despite being on 2 antiglaucoma medications, and hence ripasudil was initiated as an additional antiglaucoma medication. The endothelial cell density was 920 cells/mm.1Figure 1: Slitlamp image (A) and anterior segment optical coherence tomography (B) illustrating reticular edema in superficial cornea after 4 months of ripasudil use.Her intraocular pressure at 1 month of starting ripasudil was 12 mm Hg. Subsequently, 3 months later, she presented with counting finger vision, honeycomb edema in the superficial cornea (Fig. 1). Ripasudil was discontinued and 1 month later, although the epithelial net-like pattern disappeared, the graft was diffusely edematous and failed to recover the clarity until a follow-up of 3 months (Supplementary Digital Content, Fig. 1C, D, http://links.lww.com/APJO/A132) when repeat endothe-lial keratoplasty was planned. Rho kinase inhibitors have gained popularity in the management of glaucoma and corneal endothelial diseases.2 Ripasudil and netarsudil are Rho kinase inhibitors approved for clinical use. Reticular bullous epithelial edema has been reported with the use of 0.02% netarsudil, which improves in some eyes after the medication is discontinued.1 In our patient, similar pattern of edema was noted with 0.4% ripasudil after 4 months of treatment, which failed to resolve on discontinuing ripasudil. The reticular epithelial edema during ripasudil treatment should be distinguished from graft rejection. The medication should be stopped promptly if cornea edema is noted. The likelihood of nonclearance of edema should be explained to the patients.

Recurrent hemorrhagic bullae of the oral mucosa

Recurrent hemorrhagic bullae of the oral mucosa

Flow Mechanism and Strength Characteristics of Textile Reinforced Concrete Mixed with Colloidal Nano-SiO2

In order to develop textile reinforced concrete (TRC) with good flowability and strength, colloidal nano-SiO2 (CNS) is adopted to improve the performance of TRC. The flowability, compressive strength, flexural strength, and four-point bending tests of TRC matrix with CNS are carried out, and the changes of internal micromorphological characteristics of TRC matrix are analyzed by combining with scanning electron microscopy. The results show that the CNS has an inhibitory effect on the flowability of TRC matrix, and the greater the amount of admixture is, the smaller the slump expansion of TRC matrix is. The compressive strength and flexural strength of TRC matrix show a trend of increasing and then decreasing as the amount of CNS increases, and the compressive strength reaches the maximum at each age (7 d, 14 d, 28 d) when CNS and silica fume replace 5% cement by 1 : 4 equal mass. The flexural strength reaches the maximum at each age (7 d, 14 d, 28 d) when 5% cement is replaced by CNS and silica fume with 3 : 7 equal mass. The flexural strength increases with the increase of CNS admixture. It is found by electron microscope scanning that the incorporation of CNS consumes more Ca(OH)2, refines the Ca(OH)2 crystal size, and generates more C-S-H gels. These C-S-H gels are distributed in a net-like pattern inside the concrete, filling the internal pores, effectively densifying the interfacial transition zone between the cementitious material and the aggregates, and optimizing the internal structure.

Livedo Racemosa – The Pathophysiology of Decompression-Associated Cutis Marmorata and Right/Left Shunt

Decompression sickness and arterial gas embolism, collectively known as decompression illness (DCI), are serious medical conditions that can result from compressed gas diving. DCI can present with a wide range of physiologic and neurologic symptoms. In diving medicine, skin manifestations are usually described in general as cutis marmorata (CM). Mainly in the Anglo-American literature the terms cutis marmorata, livedo reticularis (LR), and livedo racemosa (LRC) are used interchangeably but actually describe pathophysiologically different phenomena. CM is a synonym for LR, which is a physiological and benign, livid circular discoloration with a net-like, symmetric, reversible, and uniform pattern. The decompression-associated skin discolorations, however, correspond to the pathological, irregular, broken netlike pattern of LRC. Unlike in diving medicine, in clinical medicine/dermatology the pathology of livedo racemosa is well described as a thrombotic/embolic occlusion of arteries. This concept of arterial occlusion suggests that the decompression-associated livedo racemosa may be also caused by arterial gas embolism. Recent studies have shown a high correlation of cardiac right/left (R/L) shunts with arterial gas embolism and skin bends in divers with unexplained DCI. To further investigate this hypothesis, a retrospective analysis was undertaken in a population of Austrian, Swiss, and German divers. The R/L shunt screening results of 18 divers who suffered from an unexplained decompression illness (DCI) and presented with livedo racemosa were retrospectively analyzed. All of the divers were diagnosed with a R/L shunt, 83% with a cardiac shunt [patent foramen ovale (PFO)/atrium septum defect (ASD)], and 17% with a non-cardiac shunt. We therefore not only confirm this hypothesis but when using appropriate echocardiographic techniques even found a 100% match between skin lesions and R/L shunt. In conclusion, in diving medicine the term cutis marmorata/livedo reticularis is used incorrectly for describing the actual pathology of livedo racemosa. Moreover, this pathology could be a good explanation for the high correlation of livedo racemosa with cardiac and non-cardiac right/left shunts in divers without omission of decompression procedures.

A new interpretation of the enigmatic fossil arthropod Anhelkocephalon handlirschi Bill, 1914 – important insights in the morphology of Cyclida

Anhelkocephalon handlirschiBill, 1914 has been described as a representative of Isopoda (woodlice and relatives). Fossils of A. handlirschi come from the Grès à Voltzia Formation in western France, close to the German border. The Grès à Voltzia Formation (Voltziensandstein) is Triassic in age; lithostratigraphically, it belongs to the Buntsandstein Group. Based on the morphology of the type material and one additional specimen, we interpret A. handlirschi not as a representative of Isopoda, but as a representative of Cyclida. Cyclida is an extinct group of Euarthropoda, the representatives of which have a circular to oval outline of the body (in dorsal view). One of the herein studied specimens has aspects of appendage morphology preserved, which, in general, is a rare case for cyclidans. The herein studied specimens also add new features to the knowledge about the morphology of Cyclida, such as a net-like pattern on the dorsal body side.

Hétérogénéité clinique du mycosis fongoïde poïkilodermique : étude rétrospective de 12 cas

Poikilodermatous mycosis fungoides is a rare and indolent clinical variant of mycosis fungoides (MF). It can be difficult to distinguish from poikilodermatous parapsoriasis, a group of chronical dermatoses that may sometimes progress to MF. We aimed to specify the clinical, histopathological and developmental features of these entities by means of a retrospective study of 12 cases followed in our center. We identified cases of poikiloderma for which a diagnosis of MF or parapsoriasis was made by the physician. Photographs and histological slides were reviewed, and a final diagnosis of MF was made if the International Society for Cutaneous Lymphoma criteria for the diagnosis of early MF were fulfilled. Twelve patients were included, 10 of whom met of the MF criteria. 5 patients had large poikilodermatous patches or thin, well-defined plaques; 3 patients had the same lesions associated with classical MF lesions; finally, 4 patients had widespread ill-defined erythematous lesions in a net-like pattern, described as parakeratosis variegata, including 3 MF. 2 patients with well-defined lesions (one associated with classical MF lesions) progressed to the tumoral stage whereas none of the patients with parakeratosis variegata presented such progression. A total of 5 patients had a high skin phototype (IV and V). Two patients had squamous cell carcinoma on poikilodermatous lesions. Our study suggests that poikilodermatous MF covers a heterogeneous clinical spectrum comprising on one hand a presentation of delimited lesions sharing classical MF risk of progression, and on the other, an entity similar to parakeratosis variegata, an entity overlooked in the French nomenclature, which was particularly benign in our small series, raising the question of its affiliation to the MF group. This question merits further investigation in a larger-scale study.

Critical microstructures and defects in heterostructured materials and their effects on mechanical properties

Systematic study was conducted on the microstructures and mechanical properties of nickel samples with two distinct types of heterostructures. The first is featured with coarse-grained lamellae embedded in a matrix consisting of a very high density of dislocation structures. The second is featured with coarse-grained zones embedded in the ultrafine-grained matrix. The second type of heterostructures exhibits better strength and ductility, although it has a smaller average grain size than the first type. The zone boundaries in the second type of heterostructures are less prone to cracking than those in the first type. Intersecting micro-shear-bands formed net-like patterns in the second type of heterostructures during tensile deformation. This is the first ever observation of structural micro-shear-bands in a heterostructured material. It supports the claim that heterostructure promotes the formation of dispersive shear bands. In contrast, a macroscopic shear band formed and caused early failure of the sample with the first type of heterostructures. Our results indicate that well-developed ultrafine/nano grained matrix in heterostructured materials are necessary for preventing crack formation and shear band localization. This should be considered as a key factor for optimizing the mechanical properties of heterostructured materials.

Ectomesenchymal chondromyxoid tumor of the tongue, a rare and benign lesion

Ectomesenchymal chondromyxoid tumor is a rare benign intraoral soft tissue neoplasm. Till date, 93 cases have been reported in literature. Clinically, it presents as a slowly growing, painless, firm, submucosal swelling mainly occurring on the anterior two thirds of the dorsum of the tongue. Histopathologically, the tumor is characterized by a well circumscribed, lobular proliferation of round, polygonal, or fusiform cells in a net-like pattern in a myxoid to chondromyxoid background. Although it shows a morphological resemblance to myoepitheliomas of soft tissue and skin, the exact histogenesis remains unclear; a recent publication of a large series has demonstrated recurrent RREB1-MKL2 gene fusions in 90% of the cases, suggesting the possibility of a new entity. The diagnosis is largely supported by immunhistochemical investigations. Here, we present a new case of ECT occurring in a 62-year-old male who presented with a leading complaint of slowly growing painless mass arising from the anterior part of the tongue measuring about 3 cm. This lesion was diagnosed 4 years before recent admittance, but the patient did not undergo the scheduled surgical intervention and was lost to follow-up. As the tumor was still persisting and moderately enlarging, he came back to our clinic. Finally, the mass was completely resected; after 24 month of follow-up, he is doing well, with no signs of recurrence. Orv Hetil. 2019; 160(33): 1319-1323.

IOUS and CE-IOUS during hepatic resection for patients with hepatocellular carcinoma in liver cirrhosis1.

To retrospectively evaluate the role of intraoperative ultrasonography (IOUS) and contrast-enhanced IOUS (CE-IOUS) for the patients with hepatocellular carcinoma (HCC) undergoing hepatic resection (HR). Twenty-one consecutive patients who had undergone HR for HCC were included in this study. The patients were subject to preoperative imaging modalities including preoperative ultrasonography (Pre-US) and preoperative contrast-enhanced ultrasonography (Pre-CEUS). All the patients then underwent intraoperative ultrasonography (IOUS) and contrast-enhanced intraoperative ultrasonography (CE-IOUS) during surgery. The visualization of primary HCC and additional lesions of all patients were analyzed. Twenty-one HCCs were detected during Pre-US and the remaining six lesions (28.6%) were detected during IOUS and CE-IOUS. Thus the treatment plan was changed in 28.6% of patients. Twenty-one HCCs (diameter, 0.6-3.0 cm; mean±SD, 1.98±0.85 cm) were measured on Pre-US and remeasured on IOUS (diameter, 0.9-3.3 cm; mean±SD, 2.19±0.84 cm) (p < 0.001). The 6 additional lesions consisted of three moderately differentiated HCCs, one cholangiocarcinoma (ICC), and two high-grade dysplastic nodules (DNs). The mean maximal diameter of the 6 additional lesions was 0.83 cm (range: 0.6-1.1 cm). The malignancy associated features such as capsule interruption, echo heterogeneity, hypo-echoic rim, and a nodule in nodule pattern were more often depicted on IOUS than on Pre-US (all p < 0.01). On CEUS, 19 (90.5%) of 21 HCCs were hyper-enhanced in the arterial phase and washed out from the portal phase to the late phase; the remaining two (9.5%) were hypoenhanced. On CE-IOUS, tumor vasculatures were classified as four patterns: 11 (52.4%) exhibited netlike pattern, 7 (33.3%) annular pattern, 2 (9.5%) mixed pattern, and 1 (4.8%) radial pattern. 3 mHCCs and 2 DNs of six additional nodules had similar greyscale imagining features on IOUS, but they showed different enhancement patterns on CE-IOUS. The ICC showed slightly heterogeneous enhancement during the arterial phase and hypo-enhancement during the portal phase. IOUS detects more lesions and the treatment plan is changed in 28.6% of patients. HCCs were larger on IOUS than on Pre-US. The typical imaging features of HCCs were better depicted on IOUS in comparison with Pre-US. CE-IOUS can catch the details of microcirculation perfusion of HCCs more sensitively than CEUS. Both IOUS and CE-IOUS were able to provide more decision information during surgery.

Effects of Different Surface Treatments on Bond Strength of Resin Cement to Machined Pure Titanium.

To investigate the effects of grit blasting, acidic or alkaline/heat treatments, and metal primer application on the shear bond strength (SBS) of resin cement to machined commercially pure titanium (CP-Ti). Titanium plates were machined and received one of the following treatments: grit-blasting (GB), or grit-blasting followed by either acidic treatment (GB/AC) or alkaline/heat treatment (GB/AH). The specimens were randomly divided into 4 groups and treated with Rely X Ceramic Primer (RCP), Z Prime Plus (ZPP), and Alloy Primer (ALP), or without primer as the control. The pairs of titanium plates were cemented together with the Rely X Unicem cement. SBS was measured before and after thermocycling between 5°C and 55°C for 5000 cycles. SEM observation showed that honeycomb-shaped pores formed on the surface of machined CP-Ti after GB/AC treatment, whereas a uniform net-like pattern formed after GB/AH treatment. In descending order, the surface roughness was GB, GB/AC, and GB/AH. The GB/AH group showed the highest SBS among all the treatments. As for primers, ALP group showed the highest SBS, while the RCP group showed the lowest. GB followed by ALP presented the highest SBS. A fine, uniform network structure was formed on the surface of CP-Ti following GB/AH treatment, providing an effective micromechanical interlocking mechanism for resin bonding. At the same time, after AH treatment, the -OH formed on the surface of the machined CP-Ti triggered a chemical reaction with the acid monomers in the resin adhesives, creating a chemical bond. As a result, GB/AH treatment significantly improved the bond strength relative to GB/AC treatment. In addition, ALP treatment facilitated the formation of hydrogen bonds, which further improved the chemical bond strength. Finally, the combination of the effects mentioned above resulted in the most robust bond between machined CP-Ti and the resin adhesives.

Hydrodynamics of a submerging drop: Lined structures on the crown surface

Macrophotography and high-speed videofilming are used to investigate the material transfer in a falling drop upon collision with the surface of a fluid at rest. In the experiments the drops of colored water, milk, mineral oil, and seed oil fell in pure or colored water. Emphasis was placed on recording the pattern of the drop material spreading over the surface of the receiving fluid. On the continuous surface of the primary cavity and the crown the drop material is concentrated in the form of thin fibers which form a regular streaky or netlike pattern in which triangular, quadrangular, and pentagonal cells are expressed. The cell rows are ordered in the form of layers on the lateral walls and the bottom of the cavity. The fiber dimensions and the degree of their expressiveness vary in the process of flow evolution. The upper row of structures on the crown surface is formed by vertical fibers.

Microorganism-induced weathering of clay minerals in a hydromorphic soil

In order to improve the understanding of factors influencing weathering in hydromorphic soils, the clay mineral and chemical compositions, iron (hydr)oxides, organic compounds, and Sr and Nd isotopic compositions, of hydromorphic soils on the banks of the Liangzi Lake, Hubei province, south China, were investigated. The B horizon in the lower profile exhibits a distinct net-like pattern, with abundant short white veins within the red-brown matrix. Their various 87Sr/86Sr and 143Nd/144Nd isotopic compositions showed only small variations of 0.7270–0.7235 and 0.51200–0.51204, respectively, consistent with the composition of Yangtze River sediments, indicating that the soils were all derived from alluvium from the catchment. The white veins contained notably more SiO2, Al2O3, TiO2, and mobile elements relative to the red-brown matrix, while they both showed similar values for the chemical index of alteration of 86.7 and 87.1, respectively, and displayed similar degrees of weathering. The clay minerals in A, AE, and E horizons of the soil profile were illite, kaolinite, and mixed-layer illite–smectite. These same three clay minerals comprised the white net-like veins in the soil B horizon, whereas only illite and kaolinite were observed in the red-brown matrix. Iron (hydr)oxides in A, AE, and E horizons of the soil profile were hematite and goethite, whereas in the red-brown matrix of the B horizon they were hematite, goethite, and ferrihydrite. Different organic compounds were observed for the white vein and the red-brown matrix in the soil B horizon: an 18:2 fatty acid biomarker for fungi in the net-like vein, but not in the red-brown matrix. Compared with the red-brown matrix, the white net-like vein also clearly contained more mono-unsaturated fatty acids, which are sometimes associated with bacteria that have the capacity to reduce Fe(III). Thus, migration of iron and the formation of the net-like veins involved the participation of biota during the hydromorphic pedogenesis process, as ferrihydrite is usually formed with the assistance of biota. Redoximorphic processes will chemically affect phyllosilicates by changing their charge, and Fe(III) in illite may serve as electron acceptor for Fe(III)-reducing microorganisms. This leads to an increase in negative charge in the illite structure which could be neutralized by electrostatic displacement of interlayer cations and adsorption of protons, thereby promoting transformation of illite to mixed-layer illite–smectite and dissolution of the pre-existing illite mineral. Our results suggest that microorganisms brought about iron leaching and dominated the alteration of clay minerals by redox processes, and different mineral volumes formed in the net-like B horizon of the hydromorphic soil were attributed to the microorganism-induced weathering process.

Amantadine-Induced Livedo Racemosa.

Although livedo reticularis is a known adverse effect of amantadine, only limited studies have addressed this association. Livedo racemosa in contrast to livedo reticularis is characterized by a striking violaceous netlike pattern of the skin similar to livedo reticularis with a different histopathology and morphology (irregular, broken circular segments). In this case report, we present 2 cases of livedo racemosa and edema of lower extremities following amantadine treatment. The cutaneous biopsies in both cases showed intraluminal thrombi in subcutaneous blood vessels without evidence of vasculitis, which is consistent with livedo racemosa.

Drying structures of marine clay in the deionized aqueous suspension

Drying dissipative patterns during drying of marine colloidal (MC) clays were observed in the deionized aqueous suspension on a cover glass, a watch glass, and a Petri glass dish. Two kinds of broad rings (BR), i.e., BR of small particles at the outside edge and BR of large particles at the inner area from the edge, were observed. The size of the outside BR was the same as that of the initial suspension irrespective of colloidal concentration, whereas the size of the inner BR increased as colloidal concentration increased. Highly distorted multi-rings, i.e., branch-like or net-like patterns, appeared. Furthermore, no spoke lines formed except the areas at the outside edge of the dried film. These observations support the circular stacking of the anisotropic-shaped MC particles during the convectional flow process. The B type of solutes was deduced for MC from the drying patterns, where strong solute-substrate affinity especially for the small particles and weak inter-solute affinity coexist.

Livedo Reticularis: A Presenting Sign of Escherichia Coli Sepsis in a Newborn

Livedo reticularis is a red cutaneous netlike pattern that is caused by abnormalities of the microvascularization and can be associated with many other potential systemic etiologies. We describe a case of a newborn that presented with livedo reticularis on his first day of life without any obvious systemic signs. The livedo reticularis was associated with Escherichia Coli K1 meningitis as revealed by laboratory tests. Clinical infectious signs developed a few hours later. Despite appropriate antibiotics therapy, he died on his second day because of sepsis and disseminated intravascular coagulation. Cerebrospinal fluid culture, blood culture, and culture of samples from trachea showed the presence of Escherichia Coli serotype K1 with many virulence determinants. Conclusion: In newborn, livedo reticularis must not be considered as physiological, but as a potential sign of unknown severe bacterial infection. Thus, the presence of livedo reticularis must require urgent laboratory tests.

Confocal microscopy reveals uniform male reproductive anatomy in eriophyoid mites (Acariformes, Eriophyoidea) including spermatophore pump and paired vasa deferentia.

Male internal genitalia of eriophyoid mites comprise cuticle lined (anterior genital apodeme, genital chamber and ductus ejculatorius) and soft (paired vasa deferentia and single testis) organs. Three-dimensional reconstructions based on autofluorescence show that a thin-walled genital chamber is usually situated in a transverse plane and precisely copies the shape of the spermatophore. A thin vertical longitudinal plate (homologous to female longitudinal bridge) joins the genital chamber and ventral genital cuticle. The anterior genital apodeme is a separate vertical plate situated ahead of the genital chamber and provides a rigid support for it. The brightly autofluorescent ductus ejaculatorius starts from the posterior extremity of the genital chamber and goes backward. Proximally, the ductus ejaculatorius is tube-like, whereas distally, it is expanded into a sac. Confocal laser scanning microscopy observations on males, stained with phalloidin, indicate that the proximal ductus ejaculatorius is devoid of muscles whereas the distal ductus ejaculatorius possesses well-developed musculature (the "spermatophore pump"), appearing in 3D reconstructions as a hollow sphere with three apertures: one anterior and two posterior. Two thin-walled sausage-like vasa deferentia join the distal ductus ejaculatorius with a large single testis, each junction is encircled by a strong, ring-shaped muscle (musculus sphincter testiculodeferentis). Thin muscular fibers of the wall of the testis form a net-like pattern consisting of distinct polygonal cells. The topography of the male internal genitalia and musculature suggests that, contrary to previous observations, the spermatophore head might be extruded first and then the spermatophore stalk appears. The possible role of visceral and skeletal musculature, in the process of the expulsion of a spermatophore, is discussed.

Raman imaging for determining the sequence of blue pen ink crossings

This manuscript presents a preliminary investigation on the applicability of Raman imaging for non-destructive and rapid analysis of blue crossing ink lines. The MCR method was used to facilitate visualization of the distribution of inks of the same colour and the most predominant Raman signature at the crossing was used to interpret the order of application of inks. Different pen ink types, different times separating the application of the two ink lines and different paper substrates were used. From the 90 Raman images examined, the correct order of application was determined in more than 60% by direct observation. The remainder cases were not as clear due to the uneven distribution of inks and the empty spaces similar to a net-like pattern observed at the crossing. This pattern was possibly caused by physical impediments (the first ink applied acting as a physical barrier) or chemical impediments (the two inks did not stick). Such impediments were more strongly observed in the crossings involving the U. Eye pen ink, causing the complete skipping of this ink line. Moreover, most crossings showed some mixing between the two inks and it was more accentuated when the times separating the application of the inks were shorter, since the ink was fresher. The use of white or certificate papers did not seem to influence in the inks distribution nor determining the order of the inks. Although this study provided useful insights regarding crossing ink lines, future statistic studies may be helpful for more objective examinations.