Drudgery assessment and ergonomic evaluation of pedal operated Ragi (Eleusine Coracana) thresher.

BACKGROUND: Ragi (Eleusine Coracana) is a major food crop for the tribal population of India. OBJECTIVE: This study emphasizes the need to consider ergonomics aspects in the design and development of a pedal operated ragi thresher (PORT) for tribal people, and assesses the drudgery as well as ergonomic evaluation of a developed thresher against the conventional practice. METHODS: Thirty subjects (male = 15 and female = 15) from the tribal region were evaluated ergonomically. The physiological responses of the subjects were studied and their performance was compared. RESULTS: The results revealed that the working heart rate, oxygen consumption rate and overall discomfort rating were significantly higher in case of traditional threshing as compared to those in case of PORT. Postural analysis identified the traditional method as the most fatigue one as the person has to lift the hand above shoulder level repeatedly and has to sit in a squatting posture for long period. CONCLUSION: The drudgery and occupational hazards to public health involved in the traditional method of threshing was reduced by using the PORT. Furthermore, the traditional method involved continuous stressed actions across the entire body, whereas the PORT involved only the lower limbs.

Kluyveromyces marxianus: a potential biocatalyst of renewable chemicals and lignocellulosic ethanol production.

Kluyveromyces marxianus is an ascomycetous yeast which has shown promising results in cellulosic ethanol and renewable chemicals production. It can survive on a variety of carbon sources under industrially favorable conditions due to its fast growth rate, thermotolerance, and acid tolerance. K. marxianus, is generally regarded as a safe (GRAS) microorganism, is widely recognized as a powerhouse for the production of heterologous proteins and is accepted by the US Food and Drug Administration (USFDA) for its pharmaceutical and food applications. Since lignocellulosic hydrolysates are comprised of diverse monomeric sugars, oligosaccharides and potential metabolism inhibiting compounds, this microorganism can play a pivotal role as it can grow on lignocellulosic hydrolysates coping with vegetal cell wall derived inhibitors. Furthermore, advancements in synthetic biology, for example CRISPR-Cas9 (clustered regularly interspaced short palindromic repeats with Cas9)-mediated genome editing, will enable development of an engineered yeast for the production of biochemicals and biopharmaceuticals having a myriad of industrial applications. Genetic engineering companies such as Cargill, Ginkgo Bioworks, DuPont, Global Yeast, Genomatica, and several others are actively working to develop designer yeasts. Given the important traits and properties of K. marxianus, these companies may find it to be a suitable biocatalyst for renewable chemicals and fuel production on the large scale. This paper reviews the recent progress made with K. marxianus biotechnology for sustainable production of ethanol, and other products utilizing lignocellulosic sugars.

Commercial Washing Detergents-Assisted Alkaline Pretreatment for Lignocellulosic Sugars Production: A First Report.

Lignocellulosic sugars are the major renewable building blocks for green fuels and chemicals production. However, the implication of an effective pretreatment process is an inevitable process to access the biomass sugars. Alkaline pretreatment is a viable pretreatment process, causing a selective removal of lignin, with a minimum degradation of carbohydrates, increasing porosity and surface area, eventually enhancing enzymatic hydrolysis. Here, we have assessed commercial cloth washing detergents as catalytic agents, for the lignin removal from sugarcane bagasse. Three different detergents (Brilhiante® (B), Omo® (O), Sabonito Flash® (F)) were tested using three different concentrations (5, 10 and 15%) with and without pH adjustment. Pretreatment with O5pH (5% Omo®, pH 12) showed the maximum lignin removal (81.14%) and retainment of cellulose (44.15%), and hemicellulose (29.71%) in the pretreated bagasse. The maximum sugars (26.62 g/L) were released from the O10pH-pretreated sugarcane bagasse. This study shows the potential of washing detergents as the new potential catalytic agents for the pretreatment of biomass for efficient sugars recovery and retaining maximum lignin in the pretreated substrate.

Hemicellulosic Ethanol Production by Immobilized Wild Brazilian Yeast Scheffersomyces shehatae UFMG-HM 52.2: Effects of Cell Concentration and Stirring Rate.

The use of sugarcane bagasse hemicellulosic hydrolysates presents an interesting alternative to second generation (2G) ethanol production. Techniques to enhance the fermentation process, e.g., the use of immobilized cells, is one of the key factors for efficient production. Here, the effect of two important parameters (cell concentration in immobilized system and stirring rate) on the 2G ethanol production using the wild Brazilian yeast S. shehatae UFMG-HM 52.2 immobilized in calcium alginate matrix are presented. A 2(2) full factorial design of experiments was carried out to evaluate the effect of cell concentrations in sodium alginate solution for immobilized bead production (3.0, 6.0, and 9.0 g/L) and stirring rate (150, 200, and 250 rpm) for 2G ethanol production. Statistical analysis showed that the use of both variables at low levels enhanced ethanol yield (YP/S). Under these process conditions, YP/S of 0.31 g/g and ethanol productivity (Qp) of 0.12 g/L h were achieved. Results showed the potential of this immobilized yeast in 2G ethanol production from C5 sugars and demonstrate the importance of adequate cell concentration in immobilized systems, a finding that stands to increase bioprocesses yields and productivity.

Synthesis, characterization and optical properties of polymer-based ZnS nanocomposites.

Nanostructured polymer-semiconductor hybrid materials such as ZnS-poly(vinyl alcohol) (ZnS-PVA), ZnS-starch and ZnS-hydroxypropylmethyl cellulose (Zns-HPMC) are synthesized by a facile aqueous route. The obtained nanocomposites are characterized using various techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), UV/vis spectroscopy and photoluminescence (PL). XRD studies confirm the zinc blende phase of the nanocomposites and indicate the high purity of the samples. SEM studies indicate small nanoparticles clinging to the surface of a bigger particle. The Energy Dispersive Analysis by X-rays (EDAX) spectrum reveals that the elemental composition of the nanocomposites consists primarily of Zn:S. FTIR studies indicate that the polymer matrix is closely associated with ZnS nanoparticles. The large number of hydroxyl groups in the polymer matrix facilitates the complexation of metal ions. The absorption spectra of the specimens show a blue shift in the absorption edge. The spectrum reveals an absorption edge at 320, 310 and 325 nm, respectively. PL of nanocomposites shows broad peaks in the violet-blue region (420-450 nm). The emission intensity changes with the nature of capping agent. The PL intensity of ZnS-HPMC nanocomposites is found to be highest among the studied nanocomposites. The results clearly indicate that hydroxyl-functionalized HPMC is much more effective at nucleating and stabilizing colloidal ZnS nanoparticles in aqueous suspensions compared with PVA and starch.

Investigation on the chemiluminescence reaction of the phenylhydrazine-luminol-peroxide system.

We studied the chemiluminescence (CL) oxidation of phenyl hydrazine-luminol with various organic and inorganic peroxides. Maximum CL intensity for this system was obtained for t-butylhydroperoxide. The enhancement in CL depended strongly on pH and was greatest at pH 12.5. The solvent drastically enhanced the CL intensity. DMSO was found to increase the CL intensity many-fold as compared to acetonitrile and water. The effect of temperature on CL intensity has also been studied. The CL spectra revealed a broad peak at 425 nm, which suggests excited 3-aminophthalate ion as the luminophor. A mechanism to explain the reactions is suggested.

Immunomodulatory role of thyroid hormones: in vitro effect of tetraiodothyronine (T4) on mitogen induced blastogenic response of lymphocytes.

An attempt was made to find out the immunomodulatory role of thyroid hormone, tetraiodothyronine (T4), and its effect on in vitro mitogen induced blastogenesis. Human peripheral blood lymphocytes (PBL) were subjected to phytohaemagglutinin (PHA) concanavalin-A (Con. A) and pokeweed mitogen (PWM) in presence or absence of T4. Basal blastogenic response was significantly enhanced in dose related manner by T4. PHA and Con.A induced response was depressed significantly (r = -0.975 and r = -0.945) whereas less than 50 ng T4 in presence of PHA showed mild stimulation. On the other hand, PWM induced response in presence of T4 was enhanced significantly in dose related manner.

Immunomodulatory role of thyroid hormones: effect on humoral immune response to Salmonella typhi O antigen.

Effect of long term administration of thyroid hormones and the removal of thyroid on humoral antibody response to S. typhi O antigen was studied in male albino rats of HM strain. Humoral antibody response to S. typhi O antigen was enhanced in animals pretreated with T3 or T4 at a dose of 10 micrograms daily for 15 days. Administration of thyroid hormones simultaneously along with antigen, resulted in suppression of antibody response. In thyroidectomized animals, the antibody titer to S. typhi O antigen was decreased; this decrease in antibody titer was restored to normal level following hormone supplementation. Thyroidectomy significantly depressed TLC as well. Total leucocyte count and absolute lymphocyte count were increased following hormone treatment. Present findings, thus show the lymphoproliferative response of thyroid hormones and their effect on antibody response suggesting the immunomodulatory role of thyroid hormones.

Effect of thyroid hormones on delayed type hypersensitivity reaction.

The effect of long term administration of thyroid hormones and its deprivation on delayed type hypersensitivity (DTH) reaction to 2-4 dinitrochlorobenzene (DNCB) was studied. Animals were either pre-treated with thyroid hormones (T3 or T4) for 15 days and then subjected to DNCB skin test or the animals received thyroid hormones and simultaneously subjected to DNCB skin test. In both the cases DTH reaction was found to be increased significantly. When DNCB skin test was performed in the thyroidectomized animals, DNCB skin reaction was significantly decreased and the reaction was restored to normal following supplementation of thyroid hormones to the thyroidectomized animals. TLC and ALC were increased significantly following hormone treatment and thyroidectomized animals. TLC hand, induced significant depression in the count which was restored by hormone administration to the thyroidectomized animals.

Immunomodulatory role of thyroid hormones: in vivo effect of thyroid hormones on the blastogenic response of lymphoid tissues.

In an attempt to find out the mechanism of immunomodulation by thyroid hormones (T3 and T4), their in vivo effect on the blastogenic response of lymphocytes from various lymphoid tissues of hormone-treated and thyroidectomized rats were studied. The blastogenic response of lymphocytes from thymus, peripheral blood and mesenteric lymph nodes to pokeweed mitogen (PWM) was found to be increased significantly following T3 or T4 administration for 15 days or 30 days. However, the response to phytohaemagglutinin (PHA) increased only after 1 month of T3 or T4 administration. The blastogenic response of spleen cells to both PHA and PWM was, on the other hand, found to be depressed following 15 days of hormone administration. Thyroidectomy invariably induced significant depression in the blastogenic response to both PHA and PWM in lymphocytes of all the lymphoid tissues. Thyroid hormone (T3) administration was found to restore the blastogenic response of the lymphocytes of thyroidectomized animals.