Latent ion tracks were finally observed in diamond.

Injecting high-energy heavy ions in the electronic stopping regime into solids can create cylindrical damage zones called latent ion tracks. Although these tracks form in many materials, none have ever been observed in diamond, even when irradiated with high-energy GeV uranium ions. Here we report the first observation of ion track formation in diamond irradiated with 2-9 MeV C60 fullerene ions. Depending on the ion energy, the mean track length (diameter) changed from 17 (3.2) nm to 52 (7.1) nm. High resolution scanning transmission electron microscopy (HR-STEM) indicated the amorphization in the tracks, in which π-bonding signal from graphite was detected by the electron energy loss spectroscopy (EELS). Since the melting transition is not induced in diamond at atmospheric pressure, conventional inelastic thermal spike calculations cannot be applied. Two-temperature molecular dynamics simulations succeeded in the reproduction of both the track formation under MeV C60 irradiations and the no-track formation under GeV monoatomic ion irradiations.

Surface nanostructures on Nb-doped SrTiO3irradiated with swift heavy ions at grazing incidence.

A single crystal of SrTiO3doped with 0.5 wt% niobium (Nb-STO) was irradiated with 200 MeV Au32+ions at grazing incidence to characterize the irradiation-induced hillock chains. Exactly the same hillock chains are observed by using atomic force microscopy (AFM) and scanning electron microscopy (SEM) to study the relation between irradiation-induced change of surface topography and corresponding material property changes. As expected, multiple hillocks as high as 5-6 nm are imaged by AFM observation in tapping mode. It is also found that the regions in between the adjacent hillocks are not depressed, and in many cases they are slightly elevated. Line-like contrasts along the ion paths are found in both AFM phase images and SEM images, indicating the formation of continuous ion tracks in addition to multiple hillocks. Validity of preexisting models for explaining the hillock chain formation is discussed based on the present results. In order to obtain new insights related to the ion track formation, cross-sectional transmission electron microscopy (TEM) observation was performed. The ion tracks in the near-surface region are found to be relatively large, whereas buried ion tracks in the deeper region are relatively small. The results suggest that recrystallization plays an important role in the formation of small ion tracks in the deep region, whereas formation of large ion tracks in the near-surface region is likely due to the absence of recrystallization. TEM images also show shape deformation of ion tracks in the near-surface region, suggesting that material transport towards the surface is the reason for the absence of recrystallization.

Ion tracks in silicon formed by much lower energy deposition than the track formation threshold.

Damaged regions of cylindrical shapes called ion tracks, typically in nano-meters wide and tens micro-meters long, are formed along the ion trajectories in many insulators, when high energy ions in the electronic stopping regime are injected. In most cases, the ion tracks were assumed as consequences of dense electronic energy deposition from the high energy ions, except some cases where the synergy effect with the nuclear energy deposition plays an important role. In crystalline Si (c-Si), no tracks have been observed with any monomer ions up to GeV. Tracks are formed in c-Si under 40 MeV fullerene (C60) cluster ion irradiation, which provides much higher energy deposition than monomer ions. The track diameter decreases with decreasing the ion energy until they disappear at an extrapolated value of ~ 17 MeV. However, here we report the track formation of 10 nm in diameter under C60 ion irradiation of 6 MeV, i.e., much lower than the extrapolated threshold. The diameters of 10 nm were comparable to those under 40 MeV C60 irradiation. Furthermore, the tracks formed by 6 MeV C60 irradiation consisted of damaged crystalline, while those formed by 40 MeV C60 irradiation were amorphous. The track formation was observed down to 1 MeV and probably lower with decreasing the track diameters. The track lengths were much shorter than those expected from the drop of Se below the threshold. These track formations at such low energies cannot be explained by the conventional purely electronic energy deposition mechanism, indicating another origin, e.g., the synergy effect between the electronic and nuclear energy depositions, or dual transitions of transient melting and boiling.

Matrix-material dependence on the elongation of embedded gold nanoparticles induced by 4 MeV C60 and 200 MeV Xe ion irradiation.

We report the elongation of embedded Au nanoparticles (NPs) in three different matrices, i.e. amorphous carbon (a-C), crystalline indium tin oxide (InxSn1-xOz; ITO) and crystalline calcium fluoride (CaF2), under irradiations of 4 MeV C60 + cluster ions and 200 MeV Xe14+ ions. Under 4 MeV C60 cluster irradiation, strong sputtering is induced in CaF2 layer so that the whole the layer was completely lost at a fluence of 5 × 1013 ions cm-2. Au NPs were partly observed in the SiO2, probably due to the recoil implantation. Amorphous carbon (a-C) layer exhibits low sputtering loss even under 4 MeV C60 irradiation. However, the elongation in a-C layer was low. While the ITO layer showed a certain decrease in thickness under 4 MeV C60 irradiation, large elongation of Au NPs was observed under both 4 MeV C60 and 200 MeV Xe irradiation. The ITO layer preserved the crystallinity even after large elongation was induced. This is the first report of the elongation of metal NPs in a crystalline matrix.

C60 ions of 1 MeV are slow but elongate nanoparticles like swift heavy ions of hundreds MeV.

This study reports that high fluence fullerene ion (C60+) irradiation of 1-6 MeV, which was made possible by a new-type of high-flux ion source, elongates metal nanoparticles (NPs) in amorphous SiO2 as efficiently as swift heavy ions (SHIs) of 200 MeV Xe14+, i.e., two orders of the magnitude higher energy ions. Comparing the irradiation effects induced by both the beams, the stopping processes of C60 ions in SiO2 are discussed in this paper. Despite of having almost the same elongation efficiency, the C60+ irradiation induced ~10 times more efficient sputtering due to the clustering enhancement and/or the synergy effect. Ion tracks of ~10.4 nm in diameter and 60-80 nm in length were observed in crystalline SiO2 under 4 MeV C60 irradiation. While the track diameter was comparable to those by SHIs of the same electronic stopping, much shorter track lengths than those predicted by a rigid C60 molecule model indicates that the fragmentation occurred due to nuclear collisions. The elongation of the metal NPs was induced only down to the depth where the tracks were observed but not beyond.

Compound-Specific Radiocarbon Analysis by Elemental Analyzer-Accelerator Mass Spectrometry: Precision and Limitations.

We examine instrumental and methodological capabilities for microscale (10-50 µg of C) radiocarbon analysis of individual compounds in the context of paleoclimate and paleoceanography applications, for which relatively high-precision measurements are required. An extensive suite of data for 14C-free and modern reference materials processed using different methods and acquired using an elemental-analyzer-accelerator-mass-spectrometry (EA-AMS) instrumental setup at ETH Zurich was compiled to assess the reproducibility of specific isolation procedures. In order to determine the precision, accuracy, and reproducibility of measurements on processed compounds, we explore the results of both reference materials and three classes of compounds (fatty acids, alkenones, and amino acids) extracted from sediment samples. We utilize a MATLAB code developed to systematically evaluate constant-contamination-model parameters, which in turn can be applied to measurements of unknown process samples. This approach is computationally reliable and can be used for any blank assessment of small-size radiocarbon samples. Our results show that a conservative lower estimate of the sample sizes required to produce relatively high-precision 14C data (i.e., with acceptable errors of <5% on final 14C ages) and high reproducibility in old samples (i.e., F14C ≈ 0.1) using current isolation methods are 50 and 30 µg of C for alkenones and fatty acids, respectively. Moreover, when the F14C is >0.5, a precision of 2% can be achieved for alkenone and fatty acid samples containing ≥15 and 10 µg of C, respectively.

Telomere length determined by the fluorescence in situ hybridisation distinguishes malignant and benign cells in cytological specimens.

BACKGROUND: Telomeres are tandem repeats of TTAGGG at the end of eukaryotic chromosomes that play a key role in preventing chromosomal instability. The aim of the present study is to determine telomere length using fluorescence in situ hybridisation (FISH) on cytological specimens. METHODS: Aspiration samples (n = 41) were smeared on glass slides and used for FISH. RESULTS: Telomere signal intensity was significantly lower in positive cases (cases with malignancy, n = 25) as compared to negative cases (cases without malignancy, n = 16), and the same was observed for centromere intensity. The difference in DAPI intensity was not statistically significant. The ratio of telomere to centromere intensity did not show a significant difference between positive and negative cases. There was no statistical difference in the signal intensities of aspiration samples from ascites or pleural effusion (n = 23) and endoscopic ultrasound-guided FNA samples from the pancreas (n = 18). CONCLUSIONS: The present study revealed that telomere length can be used as an indicator to distinguish malignant and benign cells in cytological specimens. This novel approach may help improve diagnosis for cancer patients.

X-ray absorption near edge structure and first-principles spectral investigations of cationic disorder in MgAl2O4 induced by swift heavy ions.

Cationic disorder in the MgAl2O4 spinel induced by swift heavy ions was investigated using the X-ray absorption near edge structure. With changes in the irradiation fluences of 200 MeV Xe ions, the Mg K-edge and Al K-edge spectra were synchronously changed. The calculated spectra based on density function theory indicate that the change in the experimental spectra was due to cationic disorder between Mg in tetrahedral sites and Al in octahedral sites. These results suggest a high inversion degree to an extent that the completely random configuration is achieved in MgAl2O4 induced by the high density electronic excitation under swift heavy ion irradiation.

Hillocks created for amorphizable and non-amorphizable ceramics irradiated with swift heavy ions: TEM study.

In a previous study, we found that hillocks (i.e. surface ion tracks) can be imaged using transmission electron microscopy (TEM) by irradiating thin CeO2 samples with swift heavy ions (SHI) at oblique incidence. In the present study, the same TEM method is applied to Y3Fe5O12 (YIG) and three fluorides (CaF2, SrF2 and BaF2) for observing hillocks. For YIG, which is one of the amorphizable materials, hillocks are found to have amorphous features consistent with amorphous features of ion tracks. For the fluorides, it is found that the hillocks do not exhibit amorphous features, and they are composed of nanocrystallites. Although hillocks for YIG and CaF2 exhibit different crystallographic features, hillock diameter agrees with the molten region diameter predicted by the thermal spike model for both materials. It is found that for YIG the hillock diameter is comparable to the ion track diameter, whereas for the fluorides it is always larger than the ion track diameter. The present result shows the existence of the velocity effect for ion track diameter in CaF2. It is also found that for fluorides both hillock and ion track diameters vary in the order of cation mass (i.e. CaF2 < SrF2 < BaF2). The above results of hillocks and ion tracks for SHI-irradiated fluorides can be consistently interpreted within the framework of the thermal spike model, if melting and successive recrystallization are assumed.

Accelerated anaerobic release of K, Mg and P from surplus activated sludge for element recovery and struvite formation inhibition.

Accelerated release of potassium (K), magnesium (Mg) and phosphorus (P) from surplus activated sludge (SAS) was investigated to develop a new system for the recovery of the elements. Anaerobic cultivation of SAS during 24 h released 78% of K and about 50% of Mg and P from SAS more effectively compared to aerobic cultivation (K: 40%, Mg: 15%, P: 15%). Furthermore, the addition of sodium acetate as an organic carbon source remarkably accelerated the release of K, Mg and P from SAS under anaerobic condition. However, no increase in the maximum release efficiencies was observed. The elements released from SAS could be transferred to separate liquid with the existing mechanical thickener and be recovered as MgKPO4 by some additional process. Furthermore, the removal of the elements from SAS would inhibit the formation of struvite causing the blockage of sludge transport pipe after anaerobic digestion process of thickened sludge.

Coupling between the photo-excited cyclic π system and the 4f electronic system in a lanthanide single molecule magnet.

A new type of electronic interaction which couples two angular momenta, i.e. the angular momentum of a localized 4f system (J) and an orbital angular momentum generated in a cyclic π conjugated system by irradiation with a circularly-polarized light, has been identified in a lanthanide single molecule magnet.

Modified total meso-pancreatoduodenum excision with pancreaticoduodenectomy as a mesopancreatic plane surgery in borderline resectable pancreatic cancer.

BACKGROUND: A superior mesenteric artery (SMA)-first approach has been considered to be an efficient technique in pancreaticoduodenectomy when the SMA is a factor of borderline resectable pancreatic head cancer (BRPHC). However, this excellent procedure has limitations in terms of tumor resection with an intact coverage including the pancreatic tumor and the tumor-draining lymphovascular systems and the ability to achieve a complete regional lymphadenectomy. METHODS: A modified mesenteric plane procedure has been developed that provides improved regional lymphadenectomy and permits adjustment of the surgical approach, which is based on the direction of the tumor infiltration. RESULTS: Of 55 patients taken to surgery, 19 had peritoneal dissemination and/or liver metastasis at staging laparoscopy, and the procedure revealed tumor infiltration to the SMA and/or hepatic artery (HA) in 4 patients. Finally, 32 patients with BRPHC have undergone the procedure between April 2009 and June 2015. Twenty-four of 32 patients (75.0%) had negative resection margins, and the median number of lymph nodes harvested was 34. Lymph nodes around the SMA tested positive for metastasis in 13 patients (40.6%), and those around the HA tested positive for metastasis in 7 patients (21.9%). Complications occurred in 14 patients (43.7%), with no perioperative mortality. Overall survival rates were 65.3% at 1 year and 35.2% at 3 years. CONCLUSIONS: Short-term results with the procedure may encourage surgical management for BRPHC.

Clinical characteristics and outcomes of adenovirus infection of the urinary tract after renal transplantation.

BACKGROUND: Urinary tract infection caused by human adenovirus (HAdV) after renal transplantation (RT) results in graft loss because of concomitant nephropathy and acute rejection and may result in death because of systemic dissemination. METHODS: We assessed the time period between RT and disease onset, symptoms, treatment details, disease duration, renal graft function, outcomes, and complications. RESULTS: HAdV infection of the urinary tract occurred in 8 of 170 renal transplant recipients. Symptoms were macrohematuria in all 8 patients, dysuria in 7, and fever in 5. The median period from RT to disease onset was 367 (range, 7-1763) days, and the median disease duration was 15 (range, 8-42) days. The mean serum creatinine (sCr) level prior to onset was 1.35 ± 0.48 mg/dL and the mean maximum sCr level during disease was 2.34 ± 1.95 mg/dL. These values were increased by ≥25% in 5 patients. The mean sCr levels when symptoms resolved was 1.54 ± 0.67 mg/dL, and no significant difference was seen before, during, or after disease onset (P = 0.069). Two patients were diagnosed with HAdV viremia and 1 with acute tubulointerstitial nephritis revealed on biopsy. In addition to a reduction in immunosuppressant dosage, 2 patients received gammaglobulins and 5 received ganciclovir. CONCLUSION: Symptoms of all patients were alleviated, although some patients developed nephritis or viremia. Hence, the possibility of exacerbation should always be considered. Adequate follow-up observation should be conducted, and diligent and aggressive therapeutic intervention is required to prevent the condition from worsening.

Experimental evidence of crystalline hillocks created by irradiation of CeO2 with swift heavy ions: TEM study.

In this study, CeO2 was irradiated with 200 MeV Au ions at oblique incidence. Observation of as-irradiated samples by transmission electron microscopy (TEM) shows that hillocks are created not only at the wide surfaces, but also at the crack faces of the thin samples. Since the hillocks created at the crack faces can be imaged by TEM, their shape and crystallographic features can be revealed. From the images of hillocks created at the crack faces, many of the hillocks are found to be spherical. We present the first experimental evidence that hillocks created for CeO2 irradiated with swift heavy ions have a crystal structure whose lattice spacing and orientation coincide with those of the matrix. The mechanism of spherical crystalline hillock formation is discussed based on the present results.

Overview of the tuberculosis burden in prison institutions in Japan, 2000-2012.

BACKGROUND: Although prison inmates in Japan are considered a high-risk group for tuberculosis (TB), little is known about the overall TB burden in prisons. OBJECTIVE: To estimate the incidence and epidemiological characteristics of TB among inmates in Japan, and to perform an ecological analysis to identify an association between socio-economic factors and TB incidence in prisons. METHOD: Using the annual reports on correctional statistics, we calculated TB incidence among inmates between 2000 and 2012. Multivariate analysis was conducted with selected socio-economic variables to examine their impact on overall and age-specific incidence. RESULTS: The average TB incidence between 2000 and 2012 among inmates was 255.0 per 100,000 population. The proportion of foreigners among new inmates was the best predictor of overall TB incidence, as well as of incidence among inmates aged 20-29 and 30-39 years. The proportion of those working in the construction industry before being arrested was the best predictor of incidence among those aged 40-49 and 50-59 years. CONCLUSION: TB incidence among inmates was approximately 11 times higher than in the general population. A more detailed analysis of patient information is needed to identify specific risk groups within the incarcerated population and improve case finding.

Permanent employment or public assistance may increase tuberculosis survival among working-age patients in Japan.

OBJECTIVES: To measure the effect of employment and health insurance status on the survival of working age tuberculosis (TB) patients in Japan. METHODS: Retrospective cohort analysis of new smear-positive pulmonary TB patients aged 15-59 years registered in the Japanese national TB surveillance system between 2007 and 2010. We performed univariate and multivariate Cox proportional hazard model analysis. The survival curves for employment and health insurance status were calculated using Kaplan-Meier analysis. RESULTS: Of 9097 patients studied, 267 (2.9%) died of TB within 12 months. After adjustment with a multivariate model, employment and health insurance status were independently associated with increased risk of TB death: unemployment (HR 2.80, 95%CI 2.11-3.72), absence of insurance (HR 1.48, 95%CI 1.02-2.15). The analysis of survival curves indicated that those with public assistance had almost the same survival rate as insured patients in the unemployed group. Permanent workers (employed >30 days) had the highest survival rates, followed by casual workers (employed <30 days) and the unemployed in the insured group. CONCLUSION: Patients with permanent jobs had better survival rates than unemployed patients and casual workers. Despite being unemployed, receiving public assistance could improve survival. Health measures are required for the unemployed and casual workers.

Treatment referral system for tuberculosis patients in Dhaka, Bangladesh.

OBJECTIVE: To evaluate the referral system in an urban DOTS-based programme in Dhaka, Bangladesh, including the peri-urban area, and to identify opportunities to strengthen the system. DESIGN: This was a retrospective cohort study in which diagnosed tuberculosis (TB) patients and health providers from DOTS centres were interviewed. Research tools included pre-tested structured questionnaires and the TB patients' referral records. RESULTS: Of 4974 TB patients who were referred to the different treatment centres, only 1756 (35%) of the counterfoils of the referral slips were returned. Of 250 patients randomly selected for interview, 165 reported to a DOTS centre, 69 did not and 16 could not be traced. Variations in educational qualification, residence and the identification of DOTS centres after counselling were statistically significant (P < 0.05). Lower monthly income (RR = 7.84, RR = 5.03), distance from the centre (RR = 36.21) and those receiving treatment from pharmacies (RR = 3) or non-governmental organisations (RR = 28.48) have more risk of irregular treatment. CONCLUSION: A high proportion of referred patients were registered and initiated treatment, but many did not report to the referral treatment centre. Proper counselling and taking into account the patients' preferences during referral are essential to address access barriers to treatment adherence and improved treatment outcome.

Objectif : Evaluer le système de référence dans les programmes de DOTS urbains dans la ville de Dhaka, Bangladesh, et sa banlieue et à identifier les opportunités de renforcer ce système.Schéma : Une étude rétrospective de cohorte a interviewé les patients ayant eu un diagnostic de TB et les prestataires de soins des centres de diagnostic et de traitement (DOTS). Les outils de recherche ont inclus des questionnaires structurés pré testés et de registres de référence de patients TB.Résultats : Un total de 4974 patients TB a été référé aux différents centres de traitement. Seulement 1756 (35%) des fiches de référence des homologues ont été retournées. Parmi eux, 250 patients ont été sélectionnés au hasard pour un entretien. Parmi eux, 165 patients sont allés dans les centres DOTS, 69 n'y sont pas allés et 16 n'ont pas pu être retrouvés. On a découvert des variations statistiquement significatives en matière de niveau d'instruction, de lieu de résidence et d'identification du centre DOTS après conseil (P < 0,05). Les personnes ayant un revenu mensuel plus faible (RR = 7,84 ; RR = 5,03), la distance par rapport au centre (RR = 36,21) et prenant leur traitement dans une pharmacie et divers autres lieux ont eu un risque plus élevé (RR = 3 ; RR = 28,48) de prendre un traitement irrégulier.Conclusion : Un bon nombre de patients référés ont été enregistrés et ont mis en route le traitement mais ne sont pas retournés au centre de traitement indiqué. Un conseil adapté et le fait de tenir compte des préférences du patient pendant la référence sont essentiels pour répondre aux contraintes d'accès, pour l'adhésion au traitement et pour un meilleur résultat du traitement.

Objetivo: Evaluar el sistema de remisiones en el marco de la estrategia DOTS y reconocer las oportunidades que existen de fortalecer el sistema y se llevó a cabo en la ciudad de Dhaka, Bangladesh, incluida su zona periurbana.Método: Fue este un estudio retrospectivo de cohortes, en el cual se administraron entrevistas a los pacientes con diagnóstico de tuberculosis (TB) y a los trabajadores de salud de los centros DOTS de diagnóstico y tratamiento. Los instrumentos de la investigación consistieron en cuestionarios estructurados y registros de las remisiones de los pacientes con TB.Resultados: Se remitieron 4974 pacientes con diagnóstico de TB a los diferentes centros de tratamiento. Solo se recibieron 1756 notificaciones de contrarreferencia en los centros de origen (35%). De estos pacientes se escogieron de manera aleatoria 250 para las entrevistas. De los pacientes escogidos, 165 se habían registrado en el centro DOTS, 69 no se presentaron y fue imposible localizar a 16 de los pacientes. Los factores significativos que determinaron estas diferencias fueron el grado de instrucción, el lugar de residencia y la capacidad de seguir las instrucciones para localizar el centro DOTS (P < 0,05). Se observó que el riesgo de irregularidad en cumplimiento terapéutico se asoció con un ingreso mensual más bajo (hasta 10 000 takas, riesgo relativo [RR] = 7,84; de 10 000 takas a 20 000 takas, RR = 5,03), el hecho de vivir a una distancia mayor del centro DOTS (RR = 36,21) y de haber recibido el tratamiento en una farmacia (RR = 3) o en centros diferentes a los designados (RR = 28,48).Conclusión: Un buen número de pacientes remitidos se registró e inició el tratamiento antituberculoso, pero muchos no acudieron al centro específico DOTS. Es primordial ofrecer una orientación adecuada y tener en cuenta las preferencias del paciente durante la remisión, a fin de superar los obstáculos que existen al cumplimiento del tratamiento y obtener mejores resultados terapéuticos.

Shape elongation of Zn nanoparticles in silica irradiated with swift heavy ions of different species and energies: scaling law and some insights on the elongation mechanism.

Zinc nanoparticles (NPs) embedded in silica were irradiated with swift heavy ions (SHIs) of seven different combinations of species and energies. The shape elongation induced by the irradiations was evaluated by optical linear dichroism (OLD) spectroscopy, which is a sensitive tool for determining the change in the mean aspect ratio (AR) of NPs. Although the mean AR change indicated a linear fluence dependence in the low- and medium-fluence regions, it indicated a nonlinear dependence in the high-fluence region. The data reveal that the elongation efficiency of Zn is correlated with the electronic stopping power 'Se in silica' and is not correlated with either the 'Se in Zn' or the nuclear stopping power. The elongation efficiency plotted as a function of the 'Se in silica' revealed a linear relationship, with a threshold value of ∼2 keV nm(-1), which is the same dependence exhibited by the ion-track formation in silica. The log-log plot showed that the elongation efficiency increased linearly with Se above a critical value of ∼3 keV nm(-1) and steeply decreased with Se to the power of 5 below the critical Se. The steep decrease can be ascribed to the discontinuous nature of the ion tracks, which is expected at Se ∼ 2-4 keV nm(-1) in silica. The fluence Φ dependences of AR - 1 under various irradiations are well-normalized with the electronic energy deposition of SHIs, i.e., the product of Se and Φ, with a Se greater than the same critical value of ∼3 keV nm(-1). The normalized data above the critical value fell on a linear relation, AR(Φ) - 1 ∝ SeΦ, for SeΦ < 2 keV nm(-3) and a sublinear relation, AR(Φ) - 1 ∝ (SeΦ)(1/2) for SeΦ > 2 keV nm(-3). On the basis of these experimental results, we discuss some insights into the elongation mechanism.

Optical birefringence of Zn nanoparticles embedded in silica induced by swift heavy-ion irradiation.

Zn nanoparticles (NPs) embedded in a silica matrix subjected to irradiation with swift heavy ions of 200 MeV Xe¹4⁺ have been found to undergo shape elongation from spheres to prolate-spheroids while maintaining the major axes of the NPs in parallel alignment. The directionally-aligned Zn spheroids enable acquisition of optical properties, such as linear dichroism and birefringence. In this paper, the birefringence of the Zn spheroids was evaluated by the crossed-Nicols (XN) transmittance, where a sample was inserted between a pair of optical polarizers that were set in an orthogonal configuration. Linearly-polarized light aligned by the first polarizer was transformed to an elliptic polarization by the birefringence of the Zn spheroids. The existence of the birefringence was confirmed by the non-zero transmittance of the second polarizer in the orthogonal configuration. The sample irradiated with a fluence of 5.0 × 10¹³ ions/cm² exhibited a maximum XN transmittance of 2.1% at a photon energy of ~4 eV. The XN transmission was observed down to a fluence of 1.0 × 10¹² ions/cm², but reduced below the detection limit at a fluence of 1.0 × 10¹¹ ions/cm². The possible application of the elongated Zn NPs as a polarizer with nanometric thickness working in the near- and mid-ultraviolet region is discussed.