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In this article, we aim to spread the need for change by informing the reader about global warming and its consequences. Global warming is a phenomenon in which average global temperatures rise due to the increase in greenhouse gases (GHG) emitted and trapped in the atmosphere. These specific gases are special in that they contribute to the flow of heat within the atmosphere as they trap more heat from the sun within the atmosphere. The most influential of these gases is CO2, which most of the data analysis in this article will be focusing on. There are many issues and problems that are attributed to global warming, along with a wide array of data that relates to the topic. By analyzing such data, one can find out the global trend in climate change and even come up with potential solutions for this increasingly threatening event. The lack of action taken by world leaders is due to general negligence and a lack of an effective and coherent solution to tackle climate change. A probable solution would be to find a surrogate to the main cause of GHG emissions, which is the substantial exploitation of conventional (nonrenewable) energy sources. Renewable energy sources are excellent substitutes to conventional energy sources and one of the most effective types is wind. This energy source is currently implemented in many areas around the globe and is producing better results than in the past when conventional energy sources were in use. Although wind turbines are more efficient than solar panels in producing electricity because they are not affected by the presence of sunlight, the amount of electricity generated can fluctuate due to various factors. To adjust to these varying conditions, machine learning regression algorithms can be managed to create a wind power forecasting model that predicts how much electricity can be produced on that day according to the varying factors; it will allow people to be less dependent on those factors. This article explores the trends for climate change and the avenues for change. It must be noted that averting one’s gaze away from this urgent issue resolves nothing.

We report a technique for separate extraction of extrinsic source/drain (S/D) resistances ( $R_{\mathrm {Se}}/R_{\mathrm {De}})$ and gate bias ( $V_{{\mathbf {GS}}})$ -dependent but channel length (L)-independent intrinsic source/drain ( $R_{\mathrm {Si}}/R_{\mathrm {Di}})$ resistances for the overlap region in MOSFETs. For extraction of the overlap length ( $L_{\mathrm {ov}})$ in the heavily doped S/D regions, an analytical capacitance model for the depletion region is employed with the gate-to-source and gate-to-drain capacitance–voltage ( $C_{{{G-S}}}$ , $C_{{{G-D}}})$ characteristics. After verifying the extracted overlap length through a 2-D technology computer-aided design simulation, we successfully extract $\mathrm{V}_{\mathrm {\mathbf {GS}}}$ -dependent $R_{\mathrm {\mathbf {Si}}}= 0.9{\sim }3.7~\Omega $ and $R_{\mathrm {\mathbf {Di}}}= 1.0{\sim }3.9~\Omega $ in an n-channel MOSFET with $W=140~\mu $ m and $L=0.35 ~\mu $ m. In addition, $V_{\mathrm {\mathbf {GS}}}$ - and $L$ -independent extrinsic S/D resistances are separately extracted to be $R_{\mathrm {Se}}=5.1~\Omega $ and $R_{\mathrm {De}}= 5.0~\Omega $ , respectively.

A sub-bandgap optoelectronic differential ideality factor technique is proposed for extraction of the intrinsic density-of-states (DOS) over the bandgap in amorphous semiconductor thin-film transistors (TFTs). In the proposed technique, the gate bias-dependent differential change in the difference of ideality factors (dAη(V GS )/dV GS ) between dark and sub-bandgap photonic excitation condition is employed. With the sub-bandgap photons (hν

Polyethersulfone (PES) membranes were modified by various physico-chemical modification methods to enhance the surface hydrophilicity for application as a separation membrane to separate and collect water vapor from the flue gas. Homogeneous PES flat-sheet membranes were prepared and modified by acid treatment, blending and plasma treatment for hydrophilic surface modification. The surface characteristics of the modified PES membranes were evaluated by ATR-FTIR, XPS, SEM and contact angle measurements. No significant change in hydrophilicity was observed for the PES membranes modified by acid treatment with sulfuric acid or blending with various compositions of poloxamer as an amphiphilic PEO-PPO-PEO tri-block copolymer. On the other hand, Ar plasma treatment led to a significant increase in the hydrophilicity of the surface, depending on the plasma treatment time. As a result, the PES membrane could be the most efficiently surface-treated by applying the plasma treatment for enhancing their surface hydrophilicity.

Sub-bandgap ( $E_{\mathrm {\rm {ph}}} photonic capacitance-voltage method (PCVM) is proposed for the energy distribution [ $D_{\mathrm {\rm {it}}}(E)$ ] of interface traps at the SiO2/low temperature poly-silicon (LTPS) junction interface in LTPS thin-film transistors (TFTs). The differential capacitance–voltage ( $C$ – $V$ ) characteristics under dark and sub-bandgap photoillumination are obtained by excitation of electrons from the valence band to the empty interface states over the photoresponsive range ( $E_{F}\le E_{t}\le E_{V}+E_{\mathrm {\rm {ph}}})$ while suppressing the band-to-band electron-hole-pair generation. We applied the sub-bandgap PCVM technique to accumulation mode p-channel LTPS TFTs with $W/L=3/30~\mu \text{m}/\mu \text{m}$ . Extracted interface trap density ranges $D_{\mathrm {\rm {it}}}(E)=10^{\mathrm {\rm {10}}}- 10^{\mathrm {\rm {11}}}$ cm $^{\mathrm {\rm {-2}}}$ eV $^{\mathrm {\rm {-1}}}$ over the bandgap.

We report an extraction technique based on experimental data for intrinsic donor- and acceptor-like subgap density-of-states (DOS) over the full-energy range (EC

In this study, we developed and optimized hydrophilic polymer based solid dispersion formulations (SDs) for enhancing the aqueous solubility of eprosartan, one of poorly soluble drugs, that has been broadly used for the treatment of high blood pressure. Poly(ethylene glycol) (PEG) and poly(vinyl pyrrolidone) (PVP) based SDs were prepared by hot melting and solvent evaporation methods and the drug/polymer composition varied in the range of 1:1~1:5 with or with- out poloxamer 407 (P407) as a polymeric surfactant. The SDs prepared by solvent evaporation showed more reduced crystallinity than ones by hot melting, and PVP based SDs showed more enhanced solubility and lower crystallinity than PEG based SDs. Furthermore, it was observed from DSC and PXRD analysis that the SDs with P407 (drug:polymer: P407 = 1:5:1) demonstrated no crystallinity and the most enhanced solubility (more than 3~4 times).

In this study, poly(ethylene glycol) (PEG) was used as a hydrophilic polymer carrier to develop solid dispersion formulations for enhancing solubility and dissolution rate of pranlukast, one of poorly soluble drugs that has been broadly used for the treatment of asthma. PEG based solid dispersions with or without poloxamer were prepared by hot melting and solvent evaporation methods. The resultant solid dispersions were characterized by DSC and powder X-ray measurements, and their morphological properties were observed to be partially changed to amorphous state with reduced crystallinity. Dissolution and solubility tests showed that the solubility and dissolution rate of the solid dispersions were significantly enhanced. The solid dispersion formulation prepared by the hot melting method with a chemical composition of pranlukast:PEG:poloxamer = 1:5:1 demonstrated the most enhanced solubility and dissolution rate. The results suggest that the solid dispersions based on PEG and poloxamer are promising systems for the enhancement of solubility and bioavailability of pranlukast.

본 연구에서 우리는 시장 자료가 부족한 상황에서 개인레벨과 총량레벨 모두에서 신상품들과 기존 상 품들 간의 동태적 대체, 경쟁을 예측하는데 적합하도록 전환비용 요소가 포함된 신·구상품간 대체·경 쟁 예측 선택기반 확산 모형을 제안하고자 한다. 추가적으로, 우리는 제안된 모형을 디지털 케이블 TV, IPTV 등이 포함된 신규 유료 양방향 방송서비스들과 기존의 아날로그 케이블 TV가 대표하는 구 유료 방 송 서비스간에 벌어지는 대체 및 경쟁 예측 사례에 적용하여 본 모형의 의의를 밝히며, 또한 관련된 실 증적 시사점을 도출하고자 한다. 실증 적용 결과, 유료 방송서비스 시장에 있어선 기존 상품과 전환 비 용을 고려하지 않고 신상품 수요 예측을 하는 경우, 초기 확산 속도를 과대 추정하거나 왜곡된 예측 경 향이 존재하여, 보다 현실적이고 보수적인 신상품 수요 예측을 위해 이들의 반영이 필요함을 밝혀, 본 연구에서 제안된 모형의 의의를 확인할 수 있었다. 또한, 제안된 모형이 S자 곡선을 미리 가정하기보다, 실증 대상의 속성이 소비자의 상태전환에 미치는 영향의 정도에 따라 유연한 형태의 총량시장 성장 곡 선을 도출함을 확인하였다. 실증적으로는 여러 가격 조합에 대해 IPTV가 디지털 케이블 TV에 비해 더 선호되어 가입자 확보 면에서 우위에 있을 것임을 확인할 수 있었다. 한편, 기존 상품인 아날로그케이블 TV의 경우 열위의 서비스 속성에도 불구하고, 가격에서의 우위와 높은 전환비용의 존재로 인해 급격한 대체보다 점진적인 대체가 이루어질 가능성이 큼을 알 수 있었다.

Microcapsules containing fragrant oils as a core material were prepared byin situ polymerization, using melamine-formaldehyde prepolymer as the wall material. The several parameters, such as stirring times, stirring rates, emulsifier types, emulsifier concentrations, and the viscosity of the core materials, affect the characteristics of the microcapsules. These parameters were investigated by the analyses of microcapsule size, particle size distribution, and morphology. The average microcapsule size decreased with an increase in stirring time, stirring rate, emulsifier concentration, and viscosity of the core material. It was also found that poly(vinyl alcohol) as a protective colloid could enhance the stability of the melamine-formaldehyde microcapsules.

In this study, melamine-formaldehyde microcapsules were prepared viain situ polymerization using peppermint oil as a core material, melamine-formaldehyde as the wall material, Tween 20 as the emulsifier, and poly (vinyl alcohol) as a protective colloid. The melamine-formaldehyde microcapsules prepared in this study were then evaluated with regard to their structures, thermal properties, particle size distributions, morphologies, and release behaviors.

We report a novel technique for simultaneous extraction of subgap donor- and acceptor-like density of states [gD(E) and gA(E)] over the subgap energy range (EV

International audience; Carrier depletion and transport in a single ZnO nanowire Schottky device have been investigated at 5 K, using cathodoluminescence measurements. An exciton diffusion length of 200 nm has been determined along the nanowire axis. The depletion width is found to increase linearly with the reverse bias. The origin of this unusual dependence in semiconductor material is discussed in terms of charge location and dimensional effects on the screening of the junction electric field.

Nonpolar InGaN/GaN multiple quantum wells (MQWs) grown on the {11-00} sidewalls of c-axis GaN wires have been grown by organometallic vapor phase epitaxy on c-sapphire substrates. The structural properties of single wires are studied in detail by scanning transmission electron microscopy and in a more original way by secondary ion mass spectroscopy to quantify defects, thickness (1-8 nm) and In-composition in the wells (∼16%). The core-shell MQW light emission characteristics (390-420 nm at 5 K) were investigated by cathodo- and photoluminescence demonstrating the absence of the quantum Stark effect as expected due to the nonpolar orientation. Finally, these radial nonpolar quantum wells were used in room-temperature single-wire electroluminescent devices emitting at 392 nm by exploiting sidewall emission.

The efficacy of a novel transdermal patch containing tropisetron, a 5-hydroxytryptamine 3 (5-HT(3)) receptor antagonist, against emesis induced by anticancer agents were evaluated, in comparison with the effect of traditional tropisetron injection, in rats. The antiemetic effects were assessed via the inhibitory activity on the anticancer agent-induced kaolin-consuming behavior, a pica model representing vomiting in emesis-resistant rodents. The tropisetron patch (10mg/patch, 3.5cm(2)) was attached on the shaved back area of rats. Eight h later, each anticancer agent, cisplatin (10mg/kg, i.v.), cyclophosphamide (200mg/kg, i.p.) or doxorubicin (8mg/kg, i.v.), was administered, and thereafter, daily kaolin consumption was measured for 3 days. In comparison, the effect of daily injection of tropisetron (2mg/kg, i.v.), given 10min, 24 and 48h after the anticancer agent administration, was also evaluated. Kaolin intake greatly increased to 21, 17 and 10 folds of control ingestion on the first day after administration with the anticancer agents, cisplatin, cyclophosphamide and doxorubicin, respectively, and then gradually decreased to near control level on day 3. Such anticancer agent-induced increases in the kaolin consumption were remarkably attenuated by the attachment of tropisetron patch, resulting in the reduction to half levels, which is comparable to the efficacy of daily tropisetron injection. In particular, the blood concentration of tropisetron following patch attachment reached a maximum level of 30-40ng/ml in 12h and exhibited a plateau until detachment of the patch, in contrast to a rapid elimination with a half-life of 2.21h after injection of the drug. Taken together, it is suggested that the novel tropisetron patch could be a promising regimen for the relief of emesis, based on the long-term antiemetic effects on the diverse anticancer agents and the convenience to use the transdermal delivery system for the cancer patients who have difficulty in taking drugs due to surgical operation or gastrointestinal dysfunction.

In order to reduce the number of immunoprotected islets required in xeno- or allogenic transplants for reversing diabetes, analogues of glyburide (a sulfonylurea), an extremely hydrophobic insulin secretagogue, were synthesized and used in an attempt to produce water soluble sulfonylurea (SU) grafted polymers. After synthesizing various polymers containing glyburide analogues, a poly(N-vinyl-2-pyrrolidone-co-sulfonylurea succinyl PEO (Mw = 3000) acrylate) was found to be soluble in a cell culture medium at pH 7.4. However, solubility was only obtained by decreasing solution pH from 11 to 7.4. When the copolymer was added to the islet cell culture media at a concentration of 5 microg ml(-1) (based on the theoretical SU content of the copolymer), insulin secretion was enhanced by about 30% at low glucose concentrations of 50 and 100 mg dl(-1) compared to the control. This is equivalent to 40-60% bioactivity of glyburide. The polymer's effect on insulin secretion at a higher glucose concentration of 200 mg dl(-1) was not significant. Considering the previous results where a similar but insoluble polymer without a PEO spacer was used and the polymer showed SU bioactivity only at a glucose concentration of 50 mg dl(-1), the observations from this study indicates that the solubility of SU-grafted polymers may affect the binding of SU groups to SU receptors on the pancreatic beta-cells, resulting in improved pharmacodynamic effect of SU.