Mobile technology features and technostress in mandatory online teaching during the COVID-19 crisis.

Technostress is defined as any unhealthy condition caused by dealing with modern technology in various harmful ways; examples of technostress include addiction and stress. Even though technostress has been extensively studied in the literature, little attention has been paid to investigating technostress among academics who work in exceptional circumstances, such as crises, and who might be experiencing different psychological states due to those circumstances. To fill the gap, this study aims to explore the factors influencing technostress among school teachers. The study examined technostress's level and factor graphics structure among 692 academics from different Arab countries during COVID-19. The technostress factors and their stories were explored and measured using sequential mixed methods and confirmatory and exploratory factor analysis. The study discusses various factors' direct and indirect effects on mobile technology integration in education and the theoretical and practical implications of managing technostress in online classes. A model of techno-stressors among Arab academics was found to include: schedule overload, complexity, uncertainty, uselessness, invasion, and compulsion. The direct effect of various factors on mobile technology integration in education is mainly positive, while indirect effects are more varied. The theoretical and practical implications of managing technostress in online classes include: considering the psychological and physiological impact of technostress on students' learning performance, decreasing overall satisfaction with the learning experience, and improving the overall quality of online courses. As a result of this study's findings, a new perspective is provided on how academics in particular circumstances (in this study, the occupation of Palestine) may behave and feel toward technology in teaching.

Standoff pump-probe photothermal detection of hazardous chemicals.

A novel pump-probe Photothermal methodology using Quartz Tuning Fork (QTF) detector has been demonstrated for the first time. A tunable mid-IR Quantum Cascade Laser (QCL) and a CW fixed wavelength visible laser have been used as the pump and probe beam respectively. The developed Photothermal (PT) technique is based on Quartz Tuning Fork (QTF) detector for the detection of hazardous/explosive molecules adsorbed on plastic surface and also in aerosols form. PT spectra of various trace molecules in the fingerprinting mid- infrared spectral band 7-9 µm from distance of 25 m have been recorded. The PT spectra of explosives RDX, TNT and Acetone have been recorded at very low quantities. Acetone is the precursor of explosive Tri-Acetone Tri-Phosphate (TATP). The experimentations using pump and probe lasers, exhibit detection sensitivity of less than 5 µg/cm2 for RDX, TNT powders and of ~ 200 nl quantity for Nitrobenzene (NB) and Acetone (in liquid form) adsorbed on surfaces, from a distance of ~ 25 m. The sensitivity of the same order achieved from a distance of 15 m by using only a mid-IR tunable pump laser coupled to QTF detector. Thus the pump-probe PT technique is more sensitive in comparison to single tunable QCL pump beam technique and it is better suited for standoff detection of hazardous chemicals for homeland security as well as for forensic applications.

Microbial diversity in relation to physico-chemical properties of hot water ponds located in the Yamunotri landscape of Garhwal Himalaya.

The current study includes the assessment of physico-chemical characteristics along with the microbial diversity of hot water samples collected from three important sacred hot water springs of the Uttarakhand Himalaya close to the world-famous Hindu shrine Yamunotri temple. Hot water samples were collected for two consecutive years 2015-2016 in two sampling operations each year. A total of fifteen physico-chemical attributes of hot water were recorded. Microbes of hot water ponds were characterized by morphological, biochemical, MALDI-TOF MS, and molecular approaches. A total of twenty-two microbial strains were identified from the Surya Kund with water temperature ranging between 86 °C and 89 °C; twenty-two microbial strains were identified from the Draupadi Kund with water temperature ranging between 65 °C and 69 °C and twenty-one microbial strains were identified from the Yamunotri Tapt Kund with water temperature ranging between 45 °C and 48 °C during the study period. The present study on the assessment of physico-chemical characteristics and thermophilic microbial diversity of all the three hot water springs can be a useful reference for further studies on similar aspects in other parts of the Himalaya. The available data will also help to understand the reasons behind the curative properties of these hot water springs. This baseline information will also be instrumental for the conservation and management of these hot water springs.

Photoacoustic remote sensing of suspicious objects for defence and forensic applications.

Quantum cascade laser (QCL) based photoacoustic spectroscopic technique has been developed for detection of hazardous molecules contaminants/adsorbed on surfaces such as plastic and cloth from short standoff distances. The laser source and detection system is integrated together in a single unit. Spectra were recorded for traces of various molecules in mid-infrared spectral band (1130-1430 cm-1) from distance of 0.5 m. Pulsed quantum cascade laser source, modulated at 25 kHz and 42 kHz frequency was used to detect molecular species adsorbed on surfaces of cloth and plastic. Ultrasonic microphones operating at 25 and 42 kHz resonant frequencies were used as detectors. The photoacoustic spectra of hazardous chemicals, explosive materials and bio-chemicals such as acetic acid, PETN (pentaerythritol tetranitrate), DPA (dipicolinic acid) in very low quantities were recorded. Sensitivities of 5 and 10 µg/cm2 of these analytes were achieved with frequencies of 25 and 42 kHz respectively at distance of 0.5 m. In the present technique there was no interference of audio frequency (20 Hz to 20 kHz) and bright sunlight. The technique can be applied for screening of suspicious objects for homeland security and forensic applications. The present spectroscopic technique can be developed in man portable standalone product.

Ultrasensitive photoacoustic sensor based on quantum cascade laser spectroscopy.

The paper focuses on development of ultra-sonic detection system based on laser photoacoustic spectroscopic technique and processing of signal for detection of very low quantity chemicals, explosive materials, and mixtures of these hazardous molecules. The detection system has been developed for the first time with specially designed one side open photo-acoustic cell having high quality factor. Explosive and Hazardous materials like RDX, DNT, PETN, Gun Powder, TATP (Tri acetone tri-peroxide) and their simulants like Acetone were detected in 7 to 9µm wavelength band. Lock in amplifier electronic instrument was used for the detection of hazardous chemicals and mixture of explosives in very low quantity. Detection limit of the photoacoustic ultrasonic sensor was also carried out of powder, liquid and adsorbed on surfaces.

Contamination profile of DDT and HCH in surface sediments and their spatial distribution from North-East India.

Contamination status and spatial distribution of DDTs and HCHs were investigated in sediments collected from ponds and riverine system from districts Nagaon and Dibrugarh, North East India. A total of 113 surface sediment samples were collected from both the districts including 43 from ponds/wetlands and 70 from rivers/streams. Based on dry weight (dw), the mean concentration of ∑HCH and ∑DDT in sediments were found to be 287 ng/g (71.2-834 ng/g) and 321 ng/g (30.1-918 ng/g) for district Dibrugarh while 330 ng/g (39.2-743 ng/g) and 378 ng/g (72.5-932 ng/g) for district Nagaon, respectively. DDTs and HCHs in sediments were well influenced by total organic carbon, clay and silt content of sediments. Source identification revealed that sediment residue levels have originated from long and recent mixed source of technical HCH and Lindane for HCHs and mainly technical DDT for DDTs. Majority of samples exceeded the sediment quality guidelines (SQG) for γ-HCH, p,p'-DDT and ∑DDT indicating potential environmental risk. This baseline data can be used as reference for regular ecological and future POPs monitoring program.

Detection of biological warfare agents using ultra violet-laser induced fluorescence LIDAR.

This review has been written to highlight the threat of biological warfare agents, their types and detection. Bacterial biological agent Bacillus anthracis (bacteria causing the disease anthrax) which is most likely to be employed in biological warfare is being discussed in detail. Standoff detection of biological warfare agents in aerosol form using Ultra violet-Laser Induced Fluorescence (UV-LIF) spectroscopy method has been studied. Range-resolved detection and identification of biological aerosols by both nano-second and non-linear femto-second LIDAR is also discussed. Calculated received fluorescence signal for a cloud of typical biological agent Bacillus globigii (Simulants of B. anthracis) at a location of ~5.0 km at different concentrations in presence of solar background radiation has been described. Overview of current research efforts in internationally available working UV-LIF LIDAR systems are also mentioned briefly.

Contamination levels and spatial distribution of organochlorine pesticides in soils from India.

Organochlorine pesticides, dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH), are potential chemical pollutants extensively used for agriculture and vector control purposes due to low cost and high effectiveness. Concentrations of HCH and DDT were determined in 175 surface soil samples from different agricultural fields, fallow and urban lands of districts Nagaon and Dibrugarh, Assam, India. The mean concentrations of total HCH and total DDT were 825 ng/g (range: 98-1945 ng/g) and 903 ng/g (range: 166-2288 ng/g) in district Nagaon while 705 ng/g (range: 178-1701 ng/g) and 757 ng/g (range: 75-2296 ng/g) in district Dibrugarh, respectively. The soils from paddy fields contained highest amounts of HCH and DDT residues. Total organic carbon was found to be positively associated with soil HCH and DDT residues. Ratios of DDT/(DDD+DDE) were 1.25 and 1.82 while of α/γ HCH were 2.78 and 2.51 for districts Dibrugarh and Nagaon, respectively. Source identification revealed that soil residue levels have originated from long past and recent mixed source of technical HCH and Lindane for HCHs and mainly technical DDT for DDTs. Spatial distribution was also investigated to identify the areas with higher pesticide loadings in soil.

Organochlorine pollutants in human blood and their relation with age, gender and habitat from North-east India.

Organochlorine pesticides (OCPs) have been beneficial to man and environment but their inadvertent use has caused considerable harm to human health. Despite the proliferation of different types of pesticides, organochlorines such as HCH and DDT still account for two third of the total consumption in India because of their low cost and versatility in action again various pests. Since, Assam, a state in North-eastern part of India is an endemic area with perennial transmission where mosquito borne diseases are serious health problems; these pesticides are still being used in huge quantities in vector control as well as in agriculture. A total of 331 human blood samples were collected from district Nagaon and Dibrugarh of Assam to determine the residue levels of DDT and HCH in human blood. The concentrations of selected persistent organochlorine pollutants were measured with gas chromatography-electron capture detector. The results demonstrated that the mean levels of total DDT and HCH were 743 µg L(-1) and 627 µg L(-1) for district Nagaon while 417 µg L(-1) and 348 µg L(-1) for district Dibrugarh. The difference of total HCH and total DDT between these two districts was found to be highly significant (P<0.0001). Among DDT metabolites, the same trend was observed for both the districts as p,p-DDT was the principal component contributed 41% for Nagaon and 58% for Dibrugarh. In case of HCH residues, for Nagaon, ß-HCH was the predominant contaminant comprised more than 34% while for Dibrugarh, it was α-HCH that was contributing 43% of total HCH concentration.

Assessment of organochlorine pesticides in human milk and risk exposure to infants from North-East India.

Despite the worldwide ban on use of persistent organochlorine pesticides, their usage continued until recently in India, for vector-borne disease eradication programs and agricultural purposes. The concentrations of organochlorine contaminants, DDT and HCH, have been determined in human breast milk from Dibrugarh and Nagaon districts of Assam state, North-East India. The results demonstrated that the mean levels of total DDT were 3210 ng/g lipid wt. and 2870 ng/g lipid wt. and total HCH were 2720 ng/g lipid wt. and 2330 ng/g lipid wt. in Nagaon and Dibrugarh respectively. There was no significant difference in the levels of investigated pollutants between the two districts. Significant differences in ADI (Average daily intake) for total DDT were found between the two districts. In addition, a positive correlation was observed between OCP levels in breast milk and age of mothers. Based on OCP levels in human breast milk, the ADI by the infants has been estimated. It has been found that high daily intake of DDTs and HCHs by the infants exceeded the TDI (Tolerable daily intake) which implied that infants of the region are potentially at high risk by these contaminants.

Vibrationally selective radiative and non-radiative transitions in gaseous hydrogen molecules.

An efficient vibrationally selective technique to build-up the v″=1 vibrational levels in gaseous hydrogen is demonstrated using stimulated Raman pumping (SRP). Both photo-acoustic Raman spectroscopy (PARS) and coherent anti-Stokes Raman spectroscopy (CARS) are used to study non-radiative and radiative (v″=0 and v″=1) transitions in gaseous H(2) molecules. The population fraction in the v″=1 vibrational level has been estimated using combined photo-acoustic and coherent anti-Stokes Raman spectroscopy with stimulated Raman pumping.

Photo-fragmentation cross-section of gaseous 2,4,6-trinitrotoluene at different ultraviolet wavelengths.

The photo-fragmentation cross-section of 2,4,6-trinitrotoluene (TNT) vapor at room temperature was determined at different ultraviolet wavelengths (254, 300, 340, and 400 nm) by measuring the concentration of NO molecule with cavity ring down spectroscopy and correcting for the photo-fragmentation cross-section of NO(2). Nitric oxide (NO) molecules are produced by the TNT photo-fragmentation processes via an intermediate production of NO(2). Our results reveal that the photo-fragmentation cross-section of TNT changes appreciably with change in wavelength with xenon arc lamp illumination, increasing with decreasing excitation wavelength. The maximum value of cross-section was observed at the shortest photo-fragmentation wavelength studied (254 nm), which is closest to the wavelength of an absorption peak of TNT near 220 nm.

Study of bio-physico-chemical parameters of Mothronwala swamp, Dehradun (Uttarakhand).

Aquatic biodiversity is one of the most essential characteristics of the aquatic ecosystem formaintaining its stability and a means of coping with any environmental change. The entire stretch of the Mothronwala swamp has rich riparian vegetation for providing conducive environment for the growth of aquatic organisms. The present work has been undertaken to study the bio-physico-chemical characteristics of the swamp. The data on physico-chemical environmental variables (temperature, total dissolved solutes, size and composition of substratum, pH, dissolved oxygen, alkalinity chlorides, and hardness) have been given under the present contribution. A total of 16 genera of aquatic insects belonging to orders Trichoptera, Coleoptera, Hemiptera, Ephemeroptera, Odonata and Phylum Mollusca represented the macroinvertebrates of Mothronwala swamp. The fresh water swamp of Mothronwala is under threat due to human interference and other anthropogenic activities. Some of the natural and anthropogenic environmental problems of the Mothronwala swamp have been identified and the ameliorative measures for the protection of aquatic environment and the conservation measures for the swamp have been suggested. The qualitative study revealed the present status of the aquatic biodiversity of the swamp and also about the physico-chemical parameters, which would be very helpful for policy makers to take precautionary measures to save the swamp.

Impact of Tehri Dam on aquatic macroinvertebrate diversity of Bhagirathi, Uttarakhand (India).

Aquatic macroinvertebrate diversity in the Bhagirathi river was monitored for the period of twelve months (September 2004 to August 2005) for assessing the impact of Asia's highest dam, Tehri Dam. Comparative data on diversity of macroinvertebrates revealed that the number of taxa in the downstream stretch, especially close to the dam was significantly reduced. The velocity of water current, hydromedian depth, turbidity, dissolved oxygen and the bottom substrates of the river were found drastically influenced due to the construction activities of the dam. Macroinvertebrate diversity (Shannon-Wiener Index) was altered from 3.44 to 1.98. The members of ephemeroptera and trichoptera were drastically influenced in comparison to other macroinvertebrates.

Periphytonic diversity in Bhagirathi: preimpoundment study of Tehri dam reservoir.

Tehri hydroelectric project of 2,400 MW capacity, the Asia's highest dam constructed on the Bhagirathi river in Uttarakhand is one of the most debatable dams of the country. The fluvial system of Bhagirathi and Bhilagana has been converted into a huge lentic water reservoir of 2.62x10(9) m3 capacity. Therefore, the information on periphytonic diversity before impoundment is very important. The preimpoundment study over one year (September 2004 - August 2005) was carried out monthly to analyse the periphytonic diversity in a lotic environment of Bhagirathi, one of the parent streams of Ganges. Periphytons are the important primary producers of metarhithronic stretch of Bhagirathi. 40 taxa of periphytons, represented by the families of Bacillariophyceae (25 taxa), Chlorophyceae (11 taxa) and Myxophyceae (4 taxa), were recorded from the Bhagirathi river before impoundment. The Shannon-Weiner diversity index ranged between 3.404 to 4.360 for periphytons, which indicates a good health of the ecosystem. The present study revealed that the combined impact of velocity of the water, hydromedian depth (HMD), turbidity, dissolved oxygen, total dissolved solids (TDS), and water temperature influenced the diversity of periphytons dwelling Bhagirathi.

Laser induced moving dynamic grating in fluorescein doped boric acid glass thin films (10(-4) M).

Laser induced moving dynamics grating has been studied in fluorescein doped boric acid glass films in the limit of a weak probe and a relatively strong pump. The results have been interpreted in terms of the four-level description of a saturable absorber. Good agreement has been obtained in the experimental and the fitted results. Estimated values of the non-linear parameters such as the saturation intensity, refractive index, and also the response time of the optical non-linearity have been obtained at different strong pump beam intensity.

Hot filament-dissociation of (CH3)3SiH and (CH3)4Si, probed by vacuum ultra violet laser time of flight mass spectroscopy.

The decomposition of trimethylsilane and tetramethylsilane has been investigated for the first time, using hot wire (catalytic) at various temperatures. Trimethylsilane is catalytic-dissociated in these species SiH(2), CH(3)SiH, CH(3), CH(2)Si. Time of flight mass spectroscopy signal of these species are linearly increasing with increasing catalytic-temperature. Time of flight mass spectroscopy (TOFMS) signals of (CH(3))(3)SiH and photodissociated into (CH(3))(2)SiH are decreasing with increasing hot filament temperature. TOFMS signal of (CH(3))(4)Si is decreasing with increasing hot wire temperature, but (CH(3))(3)Si signal is almost constant with increasing the temperature. We calculated activation energies of dissociated species of the parental molecules for fundamental information of reaction kinetics for the first time. Catalytic-dissociation of trimethylsilane, and tetramethylsilane single source time of flight coupled single photon VUV (118 nm) photoionization collisionless radicals at temperature range of tungsten filament 800-2360 K. The study is focused to understand the fundamental information on reaction kinetics of these molecules at hot wire temperature, and processes of catalytic-chemical vapour deposition (Cat-CVD) technique which could be implemented in amorphous and crystalline SiC semiconductors thin films.

Localized cutaneous leishmaniasis due to Leishmania donovani and Leishmania tropica: preliminary findings of the study of 161 new cases from a new endemic focus in himachal pradesh, India.

Localized cutaneous leishmaniasis (LCL) in India is due mostly to Leishmania tropica. It is mainly endemic in the deserts of Rajasthan. Recently, Himachal Pradesh has been identified as a new endemic focus for the disease. In the last few years, the number of new cases has been increasing almost to epidemic proportions. This report presents the preliminary findings of clinico-epidemiologic and investigative results of 161 new localized cases of LCL seen between May 2001 and December 2003. The study populaton was composed of 80 males and 81 females between 10 months and 75 years of age. All were indigenous to the sub-alpine valley along the Satluj River in the mountainous region of the Kinnaur District (altitude = 700-2,900 meters). Most patients were seen from April to September and had 1-8 lesions (duration = 1-6 months) that involved mainly the face. Tissue smears were positive for amastigotes in 37% and histopathology showed non-caseating epitheloid cell granuloma in 77% of the cases. Analysis by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of the ribosomal gene region of 10 biopsy specimens showed amplicons indistinguishable from L. donovani in eight cases and L. tropica in two cases. Leishmania was cultured on modified Nicole-Novy-McNeal (NNN) medium containing RPMI 1640 medium and heat-inactivated fetal bovine serum from 13 of 38 biopsy samples. Three of these isolated strains were identified as L. donovani while a fourth was L. tropica by PCR-RFLP of the ribosomal internal transcribed spacer region. One strain had a gp63 sequence identical to that of east African strains. Another strain had a unique gp63 sequence that has not been found in L. donovani complex strains. Sand flies trapped in the cattle sheds of a few patients were identified as Phlebotomus longiductus (Parrot 1928). Treatment with intralesional sodium stibogluconate was effective in all patients without any major side effects. One patient developed lupoid leishmaniasis that responded to higher dose of sodium stibogluconate. Though rarely reported as a cause of LCL, L. donovani seems to be the predominant pathogen in this new focus of cutaneous leishmaniasis. Phlebotomus longiductus is a possible vector, albeit based on circumstantial evidence.

Continuum and discrete pulsed cavity ring down laser absorption spectra of Br2 vapor.

The absorption cross-sections at room temperature are reported for the first time, of Br2 vapor in overlapping bound-free and bound-bound transition of A(3)pi1u <-- Xsigma(g)+, X(1)pi1u <-- X(1)sigma(g)+ and B(3)pi0u <-- X(1)sigma(g)+, using cavity ring down spectroscopy (CRDS) technique. We reported here, the A(3)pi1u <-- X(1)sigma(g)+, transition is included along with the two stronger X(1)pi1u <-- X(1)sigma(g)+ and B(3)pi0u <-- X(1)sigma(g) transitions of Br2. We obtained discrete absorption cross-section in the rotational structure, the continuum absorption cross-sections, and were also able to measure the absorption cross-section in separate contribution of A(3)pi1u <-- X(1)sigma(g)+, (1)pi1u <-- X(1)sigma(g)+, and B(3)pi0u <-- X(1)sigma(g)+ transitions using CRDS method to use quantum yield of Br*((2)P(1/2)). We obtained absorption cross-section order 10(-19) cm2 and detection 10(13) molecule cm(-3) (1 mTorr) of Br2. The absorption cross-sections are increasing with increasing excitation energy in the wavelength region 510-535 nm.

Molecular elimination of Br2 in 248 nm photolysis of bromoform probed by using cavity ring-down absorption spectroscopy.

By using cavity ring-down spectroscopy technique, we have observed the channel leading to Br(2) molecular elimination following photodissociation of bromoform at 248 nm. A tunable laser beam, which is crossed perpendicular to the photolysis laser beam in a ring-down cell, is used to probe the Br(2) fragment in the B(3)Pi(ou)(+)-X(1)Sigma(g)(+) transition using the range 515-524 nm. The ring-down time lasts 500 ns, so the rotational population of the Br(2) fragment may not be nascent nature, but its vibrational population should be. The vibrational population ratio of Br(2)(upsilon=1)/Br(2)(upsilon=0)=0.8+/-0.2 implies that the fragmented Br(2) is vibrationally hot. The quantum yield of the molecular elimination reaction is 0.23+/-0.05, consistent with the values of 0.26 and 0.16 reported in 234 and 267 nm photolysis of bromoform, respectively, using velocity ion imaging. A plausible photodissociation pathway is proposed, based upon this work and ab initio calculations. The A(1)A(2), B(1)E, and C(1)A(1) singlet states of bromoform are probably excited at 248 nm. These excited states may couple to the high vibrational levels of the ground state X(1)A(1) via internal conversion. This vibrationally excited bromoform readily surpasses a reaction barrier 389.6 kJ/mol prior to decomposition. The transition state structure tends to correlate with vibrationally hot Br(2). Dissociation after internal conversion of the excited states to vibrationally excited ground state should result in a large fraction of the available energy to be partitioned in vibrational states of the fragments. The observed vibrationally hot Br(2) fragment seems to favor the dissociation pathway from high vibrational levels of the ground state. Nevertheless, the other reaction channel leading to a direct impulsive dissociation from the excited states cannot be excluded.