Double glassy states and large spontaneous and conventional exchange bias in La1.5Ca0.5CoFeO6ferrimagnetic double perovskite

The structural and magnetic properties of hole doped double perovskite La_1.5Ca_0.5CoFeO₆have been investigated by measuring x-ray photoemission spectroscopy, neutron powder diffraction and magnetization. A ferrimagnetic transition is observed atT_C∼ 167 K. The presence of anti-site disorder (ASD) in La_1.5Ca_0.5CoFeO₆has also been demonstrated. Double re-entrant cluster glass transitions (T₁∼ 11 K andT_S∼ 35 K) were observed which has been attributed to the ASD effect. The presence of both large spontaneous exchange biasH_SEB∼ 2.106 kOe and giant conventional exchange biasH_CEB∼ 1.56 T at 5 K has also been observed which can be attributed to the coexistence of long range magnetic ordering and glassy state. The experimental observations were explained with the results obtained by the density functional theory calculation. The presence of double glassy states, large exchange-bias effect and different magnetic phases make this system a potential candidate for spintronic applications.

Emergence of metamagnetic transition, re-entrant cluster glass and spin phonon coupling in Tb2CoMnO6

The double perovskite compound Tb₂CoMnO₆has been investigated using x-ray absorption spectroscopy (XAS), Raman spectroscopy, magnetic measurements andab initioband structure calculations. It is observed that both anti-ferromagnetic (AFM) and ferromagnetic (FM) phase coexist in this material. The presence of anti-site disorder (ASD) has been established from the analysis of neutron diffraction data. Moreover, a prominent metamagnetic transition is observed in theM(H) behavior that has been explained with the drastic reorientation of the pinned domain which are aligned antiparallel by the antiphase boundaries (APBs) at zero field. The ASD further gives rise to spin frustration at low temperature which leads to the re-entrant cluster glass ∼33 K. The coupling between phononic degree of freedom and spin in the system has also been demonstrated. It is observed that the theoretical calculation is consistent with that of the experimentally observed behavior.

Roles of Re-entrant cluster glass state and spin-lattice coupling in magneto-dielectric behavior of giant dielectric double perovskite La1.8Pr0.2CoFeO6

La based Co-Fe combined double perovskite (La1.8Pr0.2CoFeO6) was synthesized and the dielectric (zero-field and in-field), magnetic, x-ray absorption and Raman spectroscopy measurements have been investigated for La1.8Pr0.2CoFeO6 double perovskite. The existence of re-entrant cluster glass state is observed. The magneto-dielectric (MD) is found in two temperature regions (25-80 K and 125-275 K). It has been demonstrated that the observed MD at low and high temperatures are respectively due to the spin freezing and the spin-lattice coupling. Furthermore, the very large dielectric constant and the low loss suggest that La1.8Pr0.2CoFeO6 is very important from the application point of view.

Extraordinary magnetic properties of double perovskite Eu2CoMnO6 wide band gap semiconductor

Some novel magnetic behaviours in double perovskite Eu2CoMnO6 (ECMO) have been reported. The x-ray photoemission spectroscopy study shows the presence of mixed valence states of transition metal ions. The UV-visible absorption spectroscopic study suggests that the ECMO has a direct wide band gap. A second-order magnetic phase transition as a sudden jump in the magnetization curve has been observed around 124.5 K. The large bifurcation between the zero field cooling and field cooling, suggests existence of strong spin frustration in the system. The inverse DC susceptibility confirms the presence of the Griffiths like phase. Sharp steps in magnetization have been observed in the M-H curve at 2 K, which vanishes on increasing temperature. The AC susceptibility study demonstrates the Hopkinson like effect as well as the presence of volume spin-glass-like behaviour. The temperature dependent Raman spectrum shows the presence of spin-phonon coupling.

Probing the Griffiths like phase, unconventional dual glassy states, giant exchange bias effects and its correlation with its electronic structure in Pr2-x Sr x CoMnO6

Crystal, electronic structure, dc and ac magnetization properties of the hole substituted (Sr²⁺) and partially B-site disordered double perovskite Pr_2-x Sr _x CoMnO₆ system have been investigated. The XRD pattern analysis showed a systematic decrease in the lattice parameters owing to the enhanced oxidation states of the Co/Mn ions. The electronic structure study by XPS measurements suggested the presence of mixed valence states of the B-site ions (Co²⁺ /Co³⁺ and Mn³⁺ /Mn⁴⁺) with significant enhancement of the average oxidation states due to hole doping. The mere absence of electronic states near the Fermi level in the valence band (VB) spectra for both pure (x  =  0.0) and Sr doped (x  =  0.5) systems indicated the insulating nature of the samples. Sr substitution is observed to increase the spectral weight near the Fermi level suggesting for an enhanced conductivity of the hole doped system. The dc magnetization data divulged a Griffiths like phase above the long-range ordering temperature. A typical re-entrant spin glass like phase driven by the inherent anti-site disorder (ASD) has been recognized by ac susceptibility study for both the pure and doped systems. Most interestingly, the emergence of a new cluster glass like phase (immediately below the magnetic ordering temperature and above the spin-glass transition temperature) solely driven by the Sr substitution has been unravelled by ac magnetization dynamics study. Observation of these dual glassy states in a single system is scarce and hence placed the present system amongst the rare materials. The isothermal magnetization measurements further probed the exhibition of the giant exchange bias effect originated from the interfacial exchange interactions due to existence of low temperature antiferromagnetic clusters embedded in the glassy matrix.

Sunlight-Driven Photocatalytic Degradation of Methyl Orange Based on Bismuth Ferrite (BiFeO₃) Heterostructures Composed of Interconnected Nanosheets

Herein, we report the facile microwave-assisted synthesis, characterization and photocatalytic degradation applications of Bismuth ferrite heterostructures composed of interconnected nanosheets (BHNs). The synthesized materials were subjected to several analytical studies such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy and UV-visible spectroscopy in order to examine the morphological, structural, optical and photo catalytic properties. The structural and morphological characterizations confirmed the rhombohedral perovskite crystal structure and the formation of heterostructures composed of interconnected nanosheets for the synthesized material. The compositional characterization revealed that the synthesized material is bismuth ferrite with high purity. The BHNs were further used as efficient photocatalyst for the photocatalytic degradation of highly hazardous pollutant methyl orange under sunlight irradiation. The sunlight driven photocatalytic experiments revealed ~86% photodegradation of methyl orange dye in 150 min. The presented work revealed that the synthesized BHNs are excellent material for the photocatalytic degradation of various organic contaminants and hazardous pollutants.

Comparison of integrated sustainable biodiesel and antibacterial nano silver production by microalgal and yeast isolates

Microalgal isolates (Chlorella sp. and Spirulina sp.) and yeast isolates (Candida albicans and Saccharomyces sp.) were employed as the resources of biodiesel production and silver nanoparticle synthesis. The prominent peaks of the FTIR spectrum accustomed the efficient lipid property. The developed profile containing fatty acid methyl ester (FAME) displayed the elevated amount of both saturated (C15:0, C17:0, C21:0) and unsaturated (C17:1, C18:2, C20:4) fatty acids. The physicochemical properties analyzed by using Biodiesel analyzer V1.1.software, confirmed the competency of the isolates for sustainable biodiesel production. Biosynthesis of silvernanoparticles (AgNPs) were accomplished extracellularly by using supernatant of microalgal and yeast culture. The maximum absorbance at 420 and 421 nm under UV-visible spectra showed the presence of nanoparticles. The purity of the synthesized AgNPs were analyzed by XRD analysis. The elemental silver presence was affirmed by EDAX, SEM and AFM, the results revealed spherical crystalline shaped nanoparticles of size ranging from 2.0 to 7.3 nm. The antimicrobial efficacy of the silver nanoparticles (AgNPs) against various clinical pathogens which includes Bacillus sp., E. coli, Klebsiella sp., Proteus sp. and Staphylococcus aureus were observed. However, enhanced antimicrobial activity was displayed by the AgNPs, produced by Candida albicans (12 mm) against Bacillus sp., and E.coli, the nanoparticle produced by Chlorella sp. showed the least antagonistic activity (07 mm).

Catalytic synthesis of α-amino chromone phosphonates and their antimicrobial, toxicity and potential HIV-1 RT inhibitors based on silico screening

The α-amino phosphonates exhibit a wide range of biological properties which create demand for simple and efficient synthetic routes of new molecules. In this study synthesis of a new series of derivatives of α-amino chromone phosphonates (ACPs) was reported using RhBT catalyst. The RhBT was first prepared by simply mixing boron nitride in a solution of rhodium acetate, under inert atmosphere for a week followed by filtration (yield: 92%). The catalyst can be re-used for up to four times and showed minimal loss of activity. The ACPs was prepared in a one pot reaction containing chromone based aldehydes, aniline derivatives and diethyl phosphite. The structures of these compounds were characterized by IR, ¹H NMR, ¹³C NMR, ³¹P NMR and high resolution mass spectral analysis. The synthesized ACPs were evaluated for their antimicrobial activities against three bacteria B. cereus, M. luteus, E. coli and one fungus C. albicans. The ACPs displayed selective toxicity toward the brine shrimp (Artemia salina). Compounds 8j and 8m was found to be less toxic to the brine shrimp and may have more valuable biological application. Furthermore, molecular docking studies were conducted to predict the possible therapeutic potential of ACPs. The compounds (8i, 8j, 8k and 8m) were predicted as highly active HIV-1 reverse transcriptase inhibitors.

Feasibility and validity of using WHO adolescent job aid algorithms by health workers for reproductive morbidities among adolescent girls in rural North India

Background

High prevalence of reproductive morbidities is seen among adolescents in India. Health workers play an important role in providing health services in the community, including the adolescent reproductive health services. A study was done to assess the feasibility of training female health workers (FHWs) in the classification and management of selected adolescent girls’ reproductive health problems according to modified WHO algorithms.

Methods

The study was conducted between Jan-Sept 2011 in Northern India. Thirteen FHWs were trained regarding adolescent girls’ reproductive health as per WHO Adolescent Job-Aid booklet. A pre and post-test assessment of the knowledge of the FHWs was carried out. All FHWs were given five modified WHO algorithms to classify and manage common reproductive morbidities among adolescent girls. All the FHWs applied the algorithms on at least ten adolescent girls at their respective sub-centres. Simultaneously, a medical doctor independently applied the same algorithms in all girls. Classification of the condition was followed by relevant management and advice provided in the algorithm. Focus group discussion with the FHWs was carried out to receive their feedback.

Results

After training the median score of the FHWs increased from 19.2 to 25.2 (p – 0.0071). Out of 144 girls examined by the FHWs 108 were classified as true positives and 30 as true negatives and agreement as measured by kappa was 0.7 (0.5–0.9). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 94.3 % (88.2–97.4), 78.9 % (63.6–88.9), 92.5 % (86.0–96.2), and 83.3 % (68.1–92.1) respectively.

Discussion

A consistent and significant difference between pre and post training knowledge scores of the FHWs were observed and hence it was possible to use the modified Job Aid algorithms with ease. Limitation of this study was the munber of FHWs trained was small. Issues such as time management during routine work, timing of training, overhead cost of training etc were not taken into account.

Conclusions

Training was successful in increasing the knowledge of the FHWs about adolescent girls’ reproductive health issues. The FHWs were able to satisfactorily classify the common adolescent girls’ problems using the modified WHO algorithms.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-015-1067-x) contains supplementary material, which is available to authorized users.

Synthesis and characterization studies of MgO:CuO nanocrystals by wet-chemical method

In this report, we examine the progress in adapting these nanomaterials for several predominantly photonics device fabrication by wet-chemical method. Nanocomposite of magnesium oxide (MgO) with copper oxide (CuO) doped nanoparticles were characterized by X-ray powder diffraction (XRD) and the observed peaks are quite agreeable with the pure phase cubic structure. High-resolution transmission electron microscopic (HR-TEM) results reveal that the resultant nanopowders are porous and agglomerated with polycrystalline nano-entities. Field emission of selected-area electron diffraction (SAED) studies showed that the average size of the nanoparticles were 20nm. Photoluminescence spectra of MgO:CuO were investigated, showing emission peaks around 375nm relating to new energy levels induced by defects or defect levels generation and confocal micro-Raman images indicated that the chemical molecular vibrational band structure and morphology of the product which is spherical shaped nanoparticles with an average particle size of ∼25nm with standard deviation. The electrochemical response of MgO:CuO which is proves that the nano-copper/magnesium has high functionality due to the small size and it has higher electrochemical activity without any modifications.

Unexpected regiospecific Michael addition product: synthesis of 5,6-dihydrobenzo[1,7]phenanthrolines

The unexpected formation of 5,6-dihydrobenzo[1,7]phenanthroline instead of 5,6-dihydrobenzo[1,7]phenanthroline-3-carbonitrile in acridine molecules using Michael addition has been observed for the first time.

Radial arterial compliance measurement by fiber Bragg grating pulse recorder

In the present work, we report a novel, in vivo, noninvasive technique to determine radial arterial compliance using the radial arterial pressure pulse waveform (RAPPW) acquired by fiber Bragg grating pulse recorder (FBGPR). The radial arterial compliance of the subject can be measured during sphygmomanometric examination by the unique signatures of arterial diametrical variations and the beat-to-beat pulse pressure acquired simultaneously from the RAPPW recorded using FBGPR. This proposed technique has been validated against the radial arterial diametrical measurements obtained from the color Doppler ultrasound. Two distinct trials have been illustrated in this work and the results from both techniques have been found to be in good agreement with each other.

Public health approach to address maternal mortality

Reducing maternal mortality is one of the major challenges to health systems worldwide, more so in developing countries that account for nearly 99% of these maternal deaths. Lack of a standard method for reporting of maternal death poses a major hurdle in making global comparisons. Currently much of the focus is on documenting the "number" of maternal deaths and delineating the "medical causes" behind these deaths. There is a need to acknowledge the social correlates of maternal deaths as well. Investigating and in-depth understanding of each maternal death can provide indications on practical ways of addressing the problem. Death of a mother has serious implications for the child as well as other family members and to prevent the same, a comprehensive approach is required. This could include providing essential maternal care, early management of complications and good quality intrapartum care through the involvement of skilled birth attendants. Ensuring the availability, affordability, and accessibility of quality maternal health services, including emergency obstetric care (EmOC) would prove pivotal in reducing the maternal deaths. To increase perceived seriousness of the community regarding maternal health, a well-structured awareness campaign is needed with importance be given to avoid adolescent pregnancy as well. Initiatives like Janani Surakhsha Yojna (JSY) that have the potential to improve maternal health needs to be strengthened. Quality assessments should form an essential part of all services that are directed toward improving maternal health. Further, emphasis needs to be given on research by involving multiple allied partners, with the aim to develop a prioritized, coordinated, and innovative research agenda for women's health.

Congenital cystic lung diseases

Congenital cystic diseases of the lung are a rare but significant cause of morbidity in children and young adults presenting with respiratory distress and repeated chest infections. They consist of cystic adenomatoid malformation, bronchogenic cyst, pulmonary sequestration, and congenital lobar emphysema. Surgical treatment is a safe and an effective method of treatment. Chest X-ray and computed tomography are the key imaging modalities used for diagnosis.

A549 lung cell line activity of biosynthesized silver nanoparticles using Albizia adianthifolia leaf

Stable AgNPs were formed in vitro by reacting AgNO3 (aq) solution with the aqueous plant leaf extract. UV-vis revealed the surface plasmon resonance λmax at 448 nm and the absorbance steadily increased in intensity as a function of reaction time. Transmission electron microscope (TEM) and XRD studies were used to characterize the AgNPs; the size was 4-35 nm. Dynamic light scattering (DLS) was used as supporting evidence to determine hydrodynamic size and zeta potential recorded as 80.27 nm and -24.7 mV, respectively. FT-IR spectra suggest that AgNPs are capped with protein molecules and other water soluble phytocompounds such as saponins and glycosides which also behave as stabilizing agents; TEM images indicate a visible layer surrounding the AgNPs. Prominent absorption bands at 3380 and 1642 cm(-1) are assigned to alcohol and carbonyl groups, respectively. (1)H NMR of the neat aqueous plant extract indicates presence of a complex mixture of compounds; however the chemical shift at δ 6.0-8.0 and 1.0-4.0 ppm indicates the presence of few aromatic but abundant aliphatic compounds, respectively. Toxicity of AgNPs on lung cancer cells (A549) and normal healthy peripheral lymphocytes (PLs) at 10 μg/ml and 50 μg/ml was assessed using the MTT, ATP and lactate dehydrogenase assays. Viability data for A549 cells showed a 21% (10 μg/ml) and 73% (50 μg/ml) cell viability after 6h exposure to AgNPs compared to 117% (10 μg/ml) and 109% (50 μg/ml) cell viability of normal peripheral lymphocytes. Lactate dehydrogenase was only significantly altered at 50 μg/ml AgNPs treated cells from 2.43±0.04 units to 0.77±0.04 units.

Rotenone-induced parkinsonism elicits behavioral impairments and differential expression of parkin, heat shock proteins and caspases in the rat

Rotenone is a pesticide that inhibits mitochondrial complex I activity, thus creating an environment of oxidative stress in the cell. Many studies have employed rotenone to generate an experimental animal model of Parkinson's disease (PD) that mimics and elicits PD-like symptoms, such as motor and cognitive decline. Cytoprotective proteins including parkin and heat shock proteins (HSPs) play major roles in slowing PD progression. Moreover, evidence suggests that mitochondrial dysfunction and oxidative stress-dependent apoptotic pathways contribute to dopaminergic neuron degeneration in PD. Here, rats were chronically exposed to rotenone to confirm that it causes a debilitating phenotype and various behavioral defects. We also performed histopathological examinations of nigrostriatal, cortical and cerebellar regions of rotenone-treated brain to elucidate a plausible neurodegenerative mechanism. The results of silver, tyrosine hydroxylase (TH), parkin, ubiquitin and caspase staining of brain tissue sections further validated our findings. The stress response is known to trigger HSP in response to pharmacological insult. These protective proteins help maintain cellular homeostasis and may be capable of rescuing cells from death. Therefore, we assessed the levels of different HSPs in the rotenone-treated animals. Collectively, our studies indicated the following findings in the striatum and substantia nigra following chronic rotenone exposure in an experimental PD model: (i) behavioral deficit that correlated with histopathological changes and down regulation of TH signaling, (ii) decreased levels of the cytoprotective proteins parkin, DJ1 and Hsp70 and robust expression of mitochondrial chaperone Hsp60 according to Western blot, (iii) increased immunoreactivity for caspase 9, caspase 3 and ubiquitin and decreased parkin immunoreactivity.

Association of blindness and hearing impairment with mortality in a cohort of elderly persons in a rural area

Background:

Studies in developed nations have reported an association of blindness and hearing impairment with mortality in elderly persons.

Objectives:

To study the association of blindness and hearing impairment with mortality in a cohort of elderly persons in rural north India.

Materials and Methods:

This community-based prospective study was conducted in eleven randomly selected villages, in Ballabgarh block, Haryana. A cohort of 1422 participants, of age 60 years and above, was examined at baseline, for their visual and hearing status. Data on the sociodemographic factors, various comorbidities, activities of daily living, and self-rated health were recorded. Baseline data was collected for the period May 2008 to August 2008. Follow-up data collection for mortality was completed in December 2009. The median follow-up period was 518 days.

Results:

One hundred out of 1422 elderly (7.0%) participants died during the follow-up period. Significant hazard ratios were found after adjustment for various comorbid conditions. On adjustment for sociodemographic factors (age, sex, and literacy), neither blindness nor hearing impairment was found to be significantly associated with mortality. After adjustment for all covariates in the study, hearing impairment (Hazard Ratio = 2.13; 95% CI, 1.29 – 3.54) was found to be significantly associated with mortality in the age group ≥70 years.

Conclusions:

This study demonstrated that hearing impairment was an independent risk factor for mortality in people aged ≥70 years. Similar studies with a longer period of follow-up are required in India, to guide public health interventions.

Patterns of tobacco use across rural, urban, and urban-slum populations in a north Indian community

BACKGROUND

Tobacco is the leading cause of mortality globally and in India. The magnitude and the pattern of tobacco consumption are likely to be influenced by the geographical setting and with rapid urbanization in India there is a need to study this differential pattern.

AIM

The aim was to study the rural, urban, and urban-slum differences in patterns of tobacco use.

SETTINGS

The study was conducted in Ballabgarh block, Faridabad district, Haryana, and was a community-based cross-sectional study.

MATERIALS AND METHODS

The study was conducted in years 2003-2004 using the WHO STEPS approach with 7891 participants, approximately equal number of males and females, selected using multistage sampling from urban, urban-slum, and rural strata.

STATISTICAL ANALYSIS

The analysis was done using the SPSS 12.0 statistical package (SPSS Inc., Chicago, IL, USA). Direct standardization to the WHO world standard population was done to and chi-square and ANOVA tests were used for comparison across three study settings.

RESULTS

Self-reported tobacco use among males was as follows: urban 35.2%; urban-slums 48.3%; and rural 52.6% (P value <0.05). Self-reported tobacco use among females was as follows: Urban 3.5%; urban-slums 11.9%; and rural 17.7% (P value <0.05). More males reported daily bidi (tobacco wrapped in temburini leaf) smoking (urban 17.8%, urban-slums 36.7%, rural 44.6%) than cigarette use (urban 9.6%, urban-slums 6.3%, rural 2.9%). Females using smoked tobacco were almost exclusively using bidis (urban 1.7%, 7.9%, 11% in rural). Daily chewed tobacco use had urban, urban-slum, and rural gradients of 12%, 10.5%, and 6.8% in males respectively. Its use was low in females.

CONCLUSION

The antitobacco policies of India need to focus on bidis in antitobacco campaigns. The program activities must find ways to reach the rural and urban-slum populations.

A review of the epidemiology of diabetes in rural India

OBJECTIVE

To describe the extent of problem of diabetes in rural India based on review of available literature and examine the secular trends over a period of 15 years i.e. from 1994 to 2009.

METHODS

A systematic search was performed using electronic as well as manual methods. Studies providing details of sample size, age group of participants, criteria used for diagnosis, along with the prevalence of any of the three outcomes of interest i.e. diabetes mellitus, impaired fasting glucose (IFG) or impaired glucose tolerance (IGT), were included.

RESULTS

Analysis of secular trends reveals an increase in diabetes prevalence among rural population at a rate of 2.02 per 1000 population per year. The rate of increase was high in males (3.33 per 1000 per year) as compared to females (0.88 per 1000 per year). High prevalence of IFG and IGT has been observed in southern and northern parts of the country.

CONCLUSION

The prevalence of diabetes is rising in rural India. There is a large pool of subjects with IFG and IGT at high risk of conversion to overt diabetes. Population-level and individual-level measures are needed to combat this increasing burden of diabetes.

Global medical device nomenclature: the concept for reducing device-related medical errors

In the medical device field, there are a number of players, having quite different responsibilities and levels of understanding of the processes, but all with one common interest, that of ensuring the availability of sound medical devices to the general public. To assist in this very important process, there is a need for a common method for describing and identifying these medical devices in an unambiguous manner. The Global Medical Device Nomenclature (GMDN) now provides, for the first time, an international tool for identifying all medical devices, at the generic level, in a meaningful manner that can be understood by all users. Prior to the GMDN, many nomenclature systems existed, all built upon different structures, and used locally or nationally for special purposes, with unusual approaches. These diverse systems, although often workable in their own right, have had no impact on improving the overall situation of providing a common platform, whereby, medical devices could be correctly identified and the related data safely exchanged between the involved parties. Work by standard organizations such as, CEN (European Committee for Standardization) and ISO (International Organization for Standardization), from 1993 to 1996, resulted in a standard that specified a structure for a new nomenclature, for medical devices. In this article we are trying to explain GMDN as the prime method to reduce medical device errors, and to understand the concept of GMDN, to regulate the medical device throughout the globe. Here we also make an attempt to explain various aspects of the GMDN system, such as, the process of development of the GMDN-CEN report, purpose, benefits, and their structural considerations. In addition, there will be an explanation of the coding system, role of the GMDN agency, and their utilization in the unique device identification (UDI) System. Finally, the current area of focus and vision for the future are also mentioned.

To recognize the use of international standards for making harmonized regulation of medical devices in Asia-pacific

‘Medical Devices’ include everything from highly sophisticated, computerized, medical equipment, right down to simple wooden tongue depressors. Regulations embody the public expectations for how buildings and facilities are expected to perform and as such represent public policy. Regulators, who develop and enforce regulations, are empowered to act in the public’s interest to set this policy and are ultimately responsible to the public in this regard. Standardization contributes to the basic infrastructure that underpins society including health and environment, while promoting sustainability and good regulatory practice. The international organizations that produce International Standards are the International Electrotechnical Commission (IEC), the International Organization for Standardization (ISO), and the International Telecommunication Union (ITU). With the increasing globalization of markets, International Standards (as opposed to regional or national standards) have become critical to the trading process, ensuring a level playing field for exports, and ensuring that imports meet the internationally recognized levels of performance and safety. The development of standards is done in response to sectors and stakeholders that express a clearly established need for them. An industry sector or other stakeholder group typically communicates its requirement for standards to one of the national members. To be accepted for development, a proposed work item must receive a majority support of the participating members, who verify the global relevance of the proposed item. The regulatory authority (RA) should provide a method for the recognition of international voluntary standards and for public notification of such recognition. The process of recognition may vary from country to country. Recognition may occur by periodic publication of lists of standards that a regulatory authority has found will meet the Essential Principles. In conclusion, International standards, such as, basic standards, group standards, and product standards, are a tool for harmonizing regulatory processes, to assure the safety, quality, and performance of medical devices. Standards represent the opinion of experts from all interested parties, including industry, regulators, users, and others.