Advancement of Langmuir probe-based laser photo-detachment technique for negative ion density measurement in a high-power helicon plasma source.

In the pursuit of precise diagnostics for measuring negative ion density in a helicon plasma source (HPS), a new approach utilizing a radio frequency (RF) broadband transformer-based Langmuir probe is developed specifically for laser photo-detachment (LPD) analysis. This inductively coupled LPD technique is useful for high power RF systems in which capacitive RF noise is in the same scale as the pulsed photo-detachment signal. The signal acquired by this transformer-based probe is compared against the conventional Langmuir probe-based LPD technique, revealing a remarkable enhancement in signal fidelity through an improved signal-to-noise ratio (SNR) achieved by the RF broadband transformer methodology. In addition, the localized hydrogen negative ion density measurements obtained through this probe are harmoniously aligned with the line-averaged negative ion density derived from the cavity ringdown spectroscopy (CRDS) technique. These concurrence measurements highlight the RF broadband transformer-based approach's accuracy in capturing localized negative ion density during helicon mode operation in an HPS setup. Furthermore, the correlation of negative ion density values with RF input exhibits a consistent trend in tandem with background plasma density. Notably, both CRDS and LPD measurements ascertain negative ion densities ranging from ∼5 to 6×1016 m-3 under an RF power of 500-700 W and a pressure of 8 × 10-3 mbar, all under the influence of a 55 G axial magnetic field. These specific parameters represent the optimal operational configuration for effective negative ion production with the present experimental HPS setup. Due to its better SNR, the RF broadband transformer-based Langmuir probe emerges as a useful tool for LPD diagnostics, particularly in the presence of pervasive RF noise.

The role of MicroRNAs as early biomarkers of asbestos-related lung cancer: A systematic review and meta-analysis.

BACKGROUND: Asbestos is still the leading cause of occupational cancer mortality worldwide. Asbestos-related lung cancer (LC) and malignant pleural mesothelioma (MPM) prognosis is still poor especially at advanced stage, so early diagnosis biomarkers are needed. MicroRNAs (miRNAs) have been proposed as potential early diagnostic biomarkers of asbestos-related LC and MPM. AIM: To evaluate the role of miRNAs as diagnostic and prognostic biomarkers of asbestos-related LC and MPM by performing a literature systematic review and meta-analysis. METHODS: MEDLINE, EMBASE via Ovid, PUBMED and Cochrane library databases were systematically searched up to April 2023 to identify relevant articles. A grey literature search was also conducted using the Google Scholar platform. MeSH and free text terms for 'asbestos', 'occupational exposure', 'lung cancer', 'mesothelioma' and 'miRNAs' were used to search the literature. Our systematic review protocol was registered in the PROSPERO database. Study quality was assessed via the Newcastle-Ottawa Scale. RESULTS: From the search, 331 articles were retrieved, and, after applying our selection criteria, and exclusion of one study for poor quality, 27 studies were included in the review. Most of the studies were hospital-based case-control, conducted in Europe, and evaluated MPM among men only. MiRNAs expression was measured mainly in plasma or serum. MiR-126, miR-132-3p, and miR-103a-3p were the most promising diagnostic biomarkers for MPM, and we estimated a pooled area under the curve (AUC) of 85 %, 73 %, and 50 %, respectively. In relation to MPM prognosis, miR-197­3p resulted associated with increased survival time. MiR-126, alone and combined with miR-222, was confirmed associated also to LC diagnosis, together with miR-1254 and miR-574-5p; no miRNA was found associated to LC prognosis. CONCLUSION: Based on our systematic literature review there is suggestive evidence that the expression of specific miRNAs in the blood serum or plasma are associated with asbestos-related LC and MPM diagnosis and prognosis. Further large longitudinal studies are urgently needed to validate these findings and elucidate the underlying mechanisms given the potential important implications for patients' survival.

Determinants of CO2 emissions in upper middle-income group countries: an empirical investigation.

This study investigates the kinked exponential growth, degree of association, and causation between economic growth, energy consumption, population, trade openness, and carbon dioxide (CO2) emissions in 25 upper middle-income group countries spanning data from 1985 to 2014. The study employed first-generation and second-generation unit root tests; prior to that, the cross-sectional dependence test is also applied and panel cointegration techniques, panel FMOLS and DOLS, and panel causality techniques are employed to test the degree of association and causation among the variables. The study reveals a long-run cointegration among the variables. Results of FMOLS declare that there are negative associations between economic growth and CO2 emissions, trade openness, and carbon dioxide emissions respectively, whereas it was found that there are positive relations between energy consumption and CO2 emissions, population, and CO2 emissions. While analyzing the association through DOLS, we find that all the selected determinants of carbon dioxide emissions are directly proportional to CO2 emissions in these countries. The panel Granger causality test indicates that there is bi-directional causality between population and economic growth and between trade openness and economic growth. Finally, the study ends with some policy suggestions and new avenues for future research.

Photoelectron spectroscopy of boron-containing reactive intermediates using synchrotron radiation: BH2, BH, and BF.

Mass selected slow photoelectron spectra (SPES) of three boron-containing reactive species, BH2, BH, and BF were recorded by double imaging photoion-photoelectron coincidence spectroscopy (i2PEPICO) using synchrotron radiation. All species were generated in a flow reactor from the H-abstraction of B2H6 by F atoms created in a F2 microwave discharge. The spectrum of BH2+ exhibits a long bending mode progression with a 970 cm-1 spacing due to the large geometry change from bent to linear upon ionization. Its ionization energy was determined as 8.12 ± 0.02 eV. For BH, photoionisation from both X1Σ+ singlet and a3Π triplet state was observed, permitting the experimental determination of the singlet/triplet gap (ΔEST) from the observed IE's of 9.82 eV and 8.48 eV. In addition, a threshold photoelectron spectrum of BF was recorded, which leads to an IE of 11.11 eV and an improved value for νBF+ of 1690 cm-1. All spectra were simulated by calculating Franck-Condon factors from optimised structures based on quantum chemical calculations.

Quantification of atomic hydrogen anion density in a permanent magnet based helicon ion source (HELEN) by using pulsed ring down spectroscopy.

In the present work, a permanent magnet-based helicon plasma source (HELEN) is characterized as a negative ion source. A noninvasive diagnostic technique based on cavity ring down spectroscopy (CRDS) is developed to measure the line-integrated negative hydrogen ion (H-) density in HELEN. This paper discusses the experimental results in which negative hydrogen ion density is measured for different magnetic field, pressure, and RF (13.56 MHz) power configurations. It is observed that in high power range (800-850 W), the source is operating in helicon wave heating mode with a background plasma density of ∼1018 m-3 and electron temperature of ∼2 eV. Negative hydrogen ion density is measured by CRDS method and also by optical emission spectroscopic technique. The measured negative ion density is in the range of ∼1016 m-3 under volume mode operational condition even without any use of standard magnetic filter or cesium seeding in the downstream region. The influence of pressure variation (pressure range from 4 × 10-3 mbar to 4 × 10-2 mbar) on negative ion density production is not significant, except for a particular axial magnetic field configuration (55 G) and at 8 × 10-3 mbar pressure, where ∼34% hike is observed.

An IL-10 dominant polarization of monocytes is a feature of Indian Visceral Leishmaniasis.

Leishmania donovani, the causative parasite of Visceral Leishmaniasis (VL), deviously manipulates host monocytes/macrophages to ensure its survival. Although monocytes/macrophages from patients with VL have demonstrated an impaired oxidative burst and antigen presentation, an unanswered yet pertinent question remains as to whether they are deactivated or alternatively activated. The significantly raised plasma levels of IL-4/IL-13 and IL-10 in VL patients suggested a microenvironment conducive for alternative activation of monocytes/macrophages. Accordingly, the classical markers for IL-4-driven monocytes/macrophages [M(IL-4)] were studied namely intramonocytic CD206+ , circulating CCL22 and CCL17, and were unchanged. Furthermore, the mRNA expression of Kruppel-like factor 4 (KLF4), peroxisome proliferator-activated receptors (PPAR)-γ and arginase-I (ARG-I) in peripheral blood mononuclear cells was unaltered. However, markers for IL-10-driven monocytes/macrophages [M(IL-10)], namely soluble CD163, intramonocytic IL-10, and circulating CXCL13 were significantly increased. Monocytes/macrophages of patients with VL demonstrated an increased expression of markers for M(IL-10), along with the absence of markers for M(IL-4). Taken together, in human VL, manipulation of these IL-10 polarized monocytes-macrophages may pave the way for improved therapeutic outcomes.

Nutrient sensor O-GlcNAc transferase controls cancer lipid metabolism via SREBP-1 regulation.

Elevated O-GlcNAcylation is associated with disease states such as diabetes and cancer. O-GlcNAc transferase (OGT) is elevated in multiple cancers and inhibition of this enzyme genetically or pharmacologically inhibits oncogenesis. Here we show that O-GlcNAcylation modulates lipid metabolism in cancer cells. OGT regulates expression of the master lipid regulator the transcription factor sterol regulatory element binding protein 1 (SREBP-1) and its transcriptional targets both in cancer and lipogenic tissue. OGT regulates SREBP-1 protein expression via AMP-activated protein kinase (AMPK). SREBP-1 is critical for OGT-mediated regulation of cell survival and of lipid synthesis, as overexpression of SREBP-1 rescues lipogenic defects associated with OGT suppression, and tumor growth in vitro and in vivo. These results unravel a previously unidentified link between O-GlcNAcylation, lipid metabolism and the regulation of SREBP-1 in cancer and suggests a crucial role for O-GlcNAc signaling in transducing nutritional state to regulate lipid metabolism.

Natural killer cells contribute to hepatic injury and help in viral persistence during progression of hepatitis B e-antigen-negative chronic hepatitis B virus infection.

Hepatitis B e-antigen negative (e(-)) chronic HBV infection (CHI) encompasses a heterogeneous clinical spectrum ranging from inactive carrier (IC) state to e(-) chronic hepatitis B (CHB), cirrhosis and hepatic decompensation. In the backdrop of dysfunctional virus-specific T cells, natural killer (NK) cells are emerging as innate effectors in CHI. We characterized CD3(-) CD56(+) NK cells in clinically well-defined, treatment-naive e(-) patients in IC, e(-)CHB or decompensated liver cirrhosis (LC) phase to appraise their role in disease progression. The NK cell frequencies increased progressively with disease severity (IC 8.2%, e(-)CHB 13.2% and LC 14.4%). Higher proportion of NK cells from LC/e(-)CHB expressed CD69, NKp46, NKp44, TRAIL and perforin, the last two being prominent features of CD56(bright) and CD56(dim) NK subsets, respectively. The frequencies of CD3(-) CD56(+) NK cells together with TRAIL(+) CD56(bright) and Perforin(+) CD56(dim) NK cells correlated positively with serum alanine transaminase levels in e(-)CHB/LC. K562 cell-stimulated NK cells from e(-)CHB/LC exhibited significantly greater degranulation but diminished interferon-γ production than IC. Further, Perforin(+) NK cell frequency inversely correlated with autologous CD4(+) T-cell count in e(-) patients and ligands of NK receptors were over-expressed in CD4(+) T cells from e(-)CHB/LC relative to IC. Co-culture of sorted CD56(dim) NK cells and CD4(+) T cells from e(-)CHB showed enhanced CD4(+) T-cell apoptosis, which was reduced by perforin inhibitor, concanamycin A, suggesting a possible perforin-dependent NK cell-mediated CD4(+) T-cell depletion. Moreover, greater incidence of perforin-expressing NK cells and decline in CD4(+) T cells were noticed intrahepatically in e(-)CHB than IC. Collectively, NK cells contribute to the progression of e(-)CHI by enhanced TRAIL- and perforin-dependent cytolytic activity and by restraining anti-viral immunity through reduced interferon-γ secretion and perforin-mediated CD4(+) T-cell lysis.

Netting the malaria menace: Distribution and utilization of long-lasting insecticidal net in a malaria endemic area in Bankura, West Bengal.

BACKGROUND & OBJECTIVES: Long-lasting insecticidal net (LLIN) is considered to be a highly effective intervention against malaria under National Vector Borne Disease Control Programme in India. A cross-sectional study was undertaken to assess the coverage and utilization of LLIN and the factors related thereto. METHODS: A survey of 1300 households was carried out in Ranibandh block of Bankura district in West Bengal, India, using lot quality assurance sampling (LQAS) method. Coverage/utilization of 80% was considered as minimum acceptable norm. The weighted sample size was calculated from each village of the block. The sociodemographic, economic information of the household along with the availability and use of LLIN was collected through interview and observation. RESULTS: In total, 7320 individuals including 840 children ≤ 5 yr were visited. Overall coverage of adequate LLIN was 65.4% (± 1.5%) and for children ≤ 5 yr, it was 60.5% (± 1.3%). Overall, 66.1% (± 1.4%) people of all ages and 63.7% (± 1.4%) children ≤ 5 yr slept under LLINs in the night before the survey. Out of 26 sub-centres, distribution of LLINs in 10 sub-centres was below the accepted norm, whereas utilization was sub-optimal in 19 sub-centres. In only 18.2% (± 0.5%) households, LLINs remained hanging during daytime. Poverty, caste, education, perception regarding malarial morbidity and preventive action of LLIN were associated significantly with the distribution of LLIN. Similarly, poverty (AOR = 2.14), threat perception regarding malarial morbidity (AOR = 1.51) and mortality (AOR = 2.52) were positively associated with the use of LLIN. Full utilization of bednets by under-fives of the households was higher in villages with sub-centres. INTERPRETATION & CONCLUSION: Around two-third population of the study area was effectively covered with LLIN. Higher proportion of socially marginalized people received LLIN. Threat perception regarding malaria was directly associated with both receipt and use of LLIN. Behaviour change communication on utilization along with adequate access to LLIN needs to be strengthened.

DNA damage-induced ephrin-B2 reverse signaling promotes chemoresistance and drives EMT in colorectal carcinoma harboring mutant p53.

Mutation in the TP53 gene positively correlates with increased incidence of chemoresistance in different cancers. In this study, we investigated the mechanism of chemoresistance and epithelial-to-mesenchymal transition (EMT) in colorectal cancer involving the gain-of-function (GOF) mutant p53/ephrin-B2 signaling axis. Bioinformatic analysis of the NCI-60 data set and subsequent hub prediction identified EFNB2 as a possible GOF mutant p53 target gene, responsible for chemoresistance. We show that the mutant p53-NF-Y complex transcriptionally upregulates EFNB2 expression in response to DNA damage. Moreover, the acetylated form of mutant p53 protein is recruited on the EFNB2 promoter and positively regulates its expression in conjunction with coactivator p300. In vitro cell line and in vivo nude mice data show that EFNB2 silencing restores chemosensitivity in mutant p53-harboring tumors. In addition, we observed high expression of EFNB2 in patients having neoadjuvant non-responder colorectal carcinoma compared with those having responder version of the disease. In the course of deciphering the drug resistance mechanism, we also show that ephrin-B2 reverse signaling induces ABCG2 expression after drug treatment that involves JNK-c-Jun signaling in mutant p53 cells. Moreover, 5-fluorouracil-induced ephrin-B2 reverse signaling promotes tumorigenesis through the Src-ERK pathway, and drives EMT via the Src-FAK pathway. We thus conclude that targeting ephrin-B2 might enhance the therapeutic potential of DNA-damaging chemotherapeutic agents in mutant p53-bearing human tumors.

X-ray photonic microsystems for the manipulation of synchrotron light.

Photonic microsystems played an essential role in the development of integrated photonic devices, thanks to their unique spatiotemporal control and spectral shaping capabilities. Similar capabilities to markedly control and manipulate X-ray radiation are highly desirable but practically impossible due to the massive size of the silicon single-crystal optics currently used. Here we show that micromechanical systems can be used as X-ray optics to create and preserve the spatial, temporal and spectral correlation of the X-rays. We demonstrate that, as X-ray reflective optics they can maintain the wavefront properties with nearly 100% reflectivity, and as a dynamic diffractive optics they can generate nanosecond time windows with over 100-kHz repetition rates. Since X-ray photonic microsystems can be easily incorporated into lab-based and next-generation synchrotron X-ray sources, they bring unprecedented design flexibility for future dynamic and miniature X-ray optics for focusing, wavefront manipulation, multicolour dispersion, and pulse slicing.

Numerical study on influence of cross flow on rewetting of AHWR fuel bundle.

Numerical study on AHWR fuel bundle has been carried out to assess influence of circumferential and cross flow rewetting on the conduction heat transfer. The AHWR fuel bundle quenching under accident condition is designed primarily with radial jets at several axial locations. A 3D (r, θ, z) transient conduction fuel pin model has been developed to carry out the study with a finite difference method (FDM) technique with alternating direction implicit (ADI) scheme. The single pin has been considered to study effect of circumferential conduction and multipins have been considered to study the influence of cross flow. Both analyses are carried out with the same fluid temperature and heat transfer coefficients as boundary conditions. It has been found from the analyses that, for radial jet, the circumferential conduction is significant and due to influence of overall cross flow the reductions in fuel temperature in the same quench plane in different rings are different with same initial surface temperature. Influence of cross flow on rewetting is found to be very significant. Outer fuel pins rewetting time is higher than inner.

Dressed adiabatic and diabatic potentials to study topological effects for F + H2.

We report here on the two lowest, rigorous-accurate diabatic potential energy surfaces (PES), for the F + H2 system, as calculated by including the two dominant topological effects of this system at the low energy region, namely, the Jahn-Teller effect and the Renner-Teller effect. Both effects were treated in the most rigorous way as demanded by the Born-Oppenheimer approach. No approximations were made, and in those cases where convergence was required, it was satisfied. In other words, convergence was attained in all situations. The numerical part that includes the calculation of the two lowest ab initio adiabatic PESs and the corresponding nonadiabatic coupling terms (NACTs) was carried out using the MOLPRO program. The required diabatic potentials are calculated by employing these ab initio adiabatic PESs and the corresponding adiabatic-to-diabatic angles as obtained employing the above-mentioned ab initio NACTs. The relevance of these Renner-Teller/Jahn-Teller diabatic potentials is studied by comparing the dressed-lowest ab initio adiabatic PES and the one formed by diagonalizing the dressed-diabatic 2 × 2 potential matrix. The dressed-potentials are calculated employing the vib-rotational manifold derived for each of the three surfaces, namely, the lowest adiabatic potential and the two diabatic ones. This kind of study was recently recommended by Lipoff and Herschbach ( Mol. Phys. 2010 , 108 , 1133 ) as a "blessed-practice" for the relevance of any PES. In the present case significant differences were revealed between the two types of dressed-adiabatic PESs, eventually, indicating that the lowest, ab initio PES (due to the Born-Oppenheimer approximation) is not adequate for low energy processes.

Laparoscopic staging for apparent early stage ovarian or fallopian tube cancer. First case series from a UK cancer centre and systematic literature review.

OBJECTIVE: To describe the experience of laparoscopic staging of apparent early stage adnexal cancers. METHODS: Prospectively collected data on women who had laparoscopic staging for apparent early stage adnexal cancers from May 2008 to September 2012 was reviewed. All women had had a prior surgical procedure at which the diagnosis was made, without comprehensive staging. A systematic MEDLINE search from 1980 to 2012 for publications on laparoscopic staging was performed. RESULTS: Thirty-five women had laparoscopic staging. Median age was 45 years (range 21-73). Median operative time was 210 min (range 90-210). Four intra-operative and one post-operative complication occurred; overall complication rate 5/35 (14%). One vena cava and one transverse colon injury underwent laparotomies for repair. Laparotomy conversion rate 2/35 (6%). Following laparoscopic staging, the cancer was upstaged for eight (23%) women; microscopic omental involvement (four women), pelvic lymph node involvement (two women), para-aortic lymph node involvement (one woman) and contra-lateral ovarian involvement (one woman). After follow up for a median of 18 months (range 3-59) the disease free survival was 94% and overall survival was 100%. Nine studies were identified on laparoscopic staging of adnexal cancer, of which this is the largest single institution series. CONCLUSIONS: This study adds to the evidence that laparoscopic staging is at least as safe as staging by laparotomy with appropriate and similar oncological outcomes, but with the advantages of minimal access surgery. We therefore advocate the use of laparoscopy to achieve surgical staging for women with presumed early stage adnexal cancer.

A tri-atomic Renner-Teller system entangled with Jahn-Teller conical intersections.

The present study concentrates on a situation where a Renner-Teller (RT) system is entangled with Jahn-Teller (JT) conical intersections. Studies of this type were performed in the past for contours that surround the RT seam located along the collinear axis [see, for instance, G. J. Halász, Á. Vibók, R. Baer, and M. Baer, J. Chem. Phys. 125, 094102 (2006)]. The present study is characterized by planar contours that intersect the collinear axis, thus, forming a unique type of RT-non-adiabatic coupling terms (NACT) expressed in terms of Dirac-δ functions. Consequently, to calculate the required adiabatic-to-diabatic (mixing) angles, a new approach is developed. During this study we revealed the existence of a novel molecular parameter, η, which yields the coupling between the RT and the JT NACTs. This parameter was found to be a pure number η = 22/π (and therefore independent of any particular molecular system) and is designated as Renner-Jahn coupling parameter. The present study also reveals an unexpected result of the following kind: It is well known that each (complete) group of states, responsible for either the JT-effect or the RT-effect, forms a Hilbert space of its own. However, the entanglement between these two effects forms a third effect, namely, the RT/JT effect and the states that take part in it form a different Hilbert space.

Dressed adiabatic and diabatic potentials for the Renner-Teller/Jahn-Teller F + H2 system.

We follow a suggestion by Lipoff and Herschbach (Mol. Phys. 2010, 108, 1133) and compare dressed potentials to get insight regarding the low-energy dynamics (e.g., cold reaction) taking place in molecular systems. In this particular case we are interested in studying the effect of topological effects on the interacting atoms. For this purpose we consider dressed adiabatic and adiabatic-via-dressed diabatic potentials in the entrance channel of reactive systems. In a recent study of this kind for the F + H2 system (J. Chem. Phys. 2012, 136, 054104), we revealed that a single Jahn-Teller conical intersection is expected to have only a mild effect on the dynamics. This fact implies that the Born-Oppenheimer approximation is expected to be valid for this system at least for low enough energies. In the present article this study is extended to include also the Renner-Teller effect as produced by the two lower degenerate Π states. As a result we consider three electronic states which enforce the use of the adiabatic-to-diabatic transformation (ADT) matrix A. The results indicate that the topological effects as produced by the extended Renner/Teller-Jahn/Teller system are strong to the level that, most likely, abolishes the Born-Oppenheimer approximation for this system, all this in contrast to our previous findings (see above publication).

Arsenic contamination: a potential hazard to the affected areas of West Bengal, India.

Arsenic contamination in groundwater is becoming more and more a worldwide problem. Nearing 50 million of people are at health risk from arsenic contamination at Ganga-Meghna-Bramhaputra basin. The experimental results of the five blocks under Malda district of West Bengal, India, showed that the arsenic concentration in groundwater (0.41-1.01 mg/l) was higher than the permissible limit for drinking water (0.01 mg/l) (WHO) and FAO (Food and Agriculture Organization) permissible limit for irrigation water (0.10 mg/l). The soil arsenic level (13.12 mg/kg) crossed the global average (10.0 mg/kg), but within the maximum acceptable limit for agricultural soil (20.0 mg/kg) recommended by the European Union. The total arsenic concentration on food crops varied from 0.000 to 1.464 mg/kg of dry weight. The highest mean arsenic concentration was found in potato (0.456 mg/kg), followed by rice grain (0.429 mg/kg). The total mean arsenic content (milligrams per kg dry weight) in cereals ranged from 0.121 to 0.429 mg/kg, in pulses and oilseeds ranged from 0.076 to 0.168 mg/kg, in tuber crops ranged from 0.243 to 0.456 mg/kg, in spices ranged from 0.031 to 0.175 mg/kg, in fruits ranged from 0.021 to 0.145 mg/kg and in vegetables ranged from 0.032 to 0.411 mg/kg, respectively. Hence, arsenic accumulation in cereals, pulses, oilseed, vegetables, spices, cole crop and fruits crop might not be safe in future without any sustainable mitigation strategies to avert the potential arsenic toxicity on the human health in the contaminated areas.

Food security and anthropometric failure among tribal children in Bankura, West Bengal.

We conducted a cross-sectional study among 188 tribal children aged 6-59 months using two-stage sampling in Bankura-I Block of Bankura district, West Bengal, India, to assess their nutritional status and its relation with household food security. Weight and height/length were measured and analyzed as per new WHO Growth Standards. Mothers of the study children were interviewed to obtain relevant information. Prevalence of Composite Index of Anthropometric Failure was 69.1%; and multiple anthropometric failures were more likely among tribal children aged 24-59 months with irregular utilization of supplementary nutrition and from households with severe grades of food security.

CASA-based sperm kinematics of environmental risk factor-exposed human semen samples designated as normozoospermic in conventional analysis.

This study was conducted after an initial epidemiological survey of patients in and around Calcutta, India, concerning their lifestyle history, degree of risk exposure and semen analysis based on conventional WHO criteria. It was found that a large group of exposed patients were showing normozoospermic semen parameters in conventional semen analysis. Hence, a selected group of subjects, designated as normozoospermic in routine analysis, but under risk factor exposure, were selected for a repeat computer aided semen analysis (CASA) and were compared with a control group. The parameters considered among CASA results were: curvilinear velocity (VCL), straight-line velocity, average path velocity (VAP), straightness index (STR), lateral head displacement (ALH) and beat cross frequency. The results depict a significant decline in the mean values of VCL (P = 0.029) and STR (P = 0.007) in the tobacco-exposed group when compared with the unexposed group. On the other hand, there was a significant decline in the mean values of VCL (P = 0.014) and ALH (P = 0.040) in the heavy metal-exposed group when compared with the unexposed group. The other parameters did not show significant change in either group. Semen samples that had been designated normozoospermic in conventional analysis were seen to be influenced by risk factors at the level of sperm motion kinetics.